The Meat Eaters

Would the controlled extinction of carnivorous species be a good thing?

Viewed from a distance, the natural world often presents a vista of sublime, majestic placidity. Yet beneath the foliage and hidden from the distant eye, a vast, unceasing slaughter rages. Wherever there is animal life, predators are stalking, chasing, capturing, killing, and devouring their prey. Agonized suffering and violent death are ubiquitous and continuous. This hidden carnage provided one ground for the philosophical pessimism of Schopenhauer, who contended that “one simple test of the claim that the pleasure in the world outweighs the pain…is to compare the feelings of an animal that is devouring another with those of the animal being devoured.”

The continuous, incalculable suffering of animals is also an important though largely neglected element in the traditional theological “problem of evil” — the problem of reconciling the existence of evil with the existence of a benevolent, omnipotent god. The suffering of animals is particularly challenging because it is not amenable to the familiar palliative explanations of human suffering. Animals are assumed not to have free will and thus to be unable either to choose evil or deserve to suffer it. Neither are they assumed to have immortal souls; hence there can be no expectation that they will be compensated for their suffering in a celestial afterlife. Nor do they appear to be conspicuously elevated or ennobled by the final suffering they endure in a predator’s jaws. Theologians have had enough trouble explaining to their human flocks why a loving god permits them to suffer; but their labors will not be over even if they are finally able to justify the ways of God to man. For God must answer to animals as well.

If I had been in a position to design and create a world, I would have tried to arrange for all conscious individuals to be able to survive without tormenting and killing other conscious individuals. I hope most other people would have done the same. Certainly this and related ideas have been entertained since human beings began to reflect on the fearful nature of their world — for example, when the prophet Isaiah, writing in the 8th century B.C.E., sketched a few of the elements of his utopian vision. He began with the abandonment of war: “They shall beat their swords into plowshares, and their spears into pruning hooks: nation shall not lift up sword against nation.” But human beings would not be the only ones to change; animals would join us in universal veganism: “The wolf also shall dwell with the lamb, and the leopard shall lie down with the kid; and the calf and the young lion and the fatling together; and the little child shall lead them. And the cow and the bear shall feed; their young ones shall lie down together; and the lion shall eat straw like the ox.” (Isaiah 2: 4 and 11: 6–7)

Isaiah was, of course, looking to the future rather than indulging in whimsical fantasies of doing a better job of Creation, and we should do the same. We should start by withdrawing our own participation in the mass orgy of preying and feeding upon the weak.

Our own form of predation is of course more refined than those of other meat-eaters, who must capture their prey and tear it apart as it struggles to escape. We instead employ professionals to breed our prey in captivity and prepare their bodies for us behind a veil of propriety, so that our sensibilities are spared the recognition that we too are predators, red in tooth if not in claw (though some of us, for reasons I have never understood, do go to the trouble to paint their vestigial claws a sanguinary hue). The reality behind the veil is, however, far worse than that in the natural world. Our factory farms, which supply most of the meat and eggs consumed in developed societies, inflict a lifetime of misery and torment on our prey, in contrast to the relatively brief agonies endured by the victims of predators in the wild. From the moral perspective, there is nothing that can plausibly be said in defense of this practice. To be entitled to regard ourselves as civilized, we must, like Isaiah’s morally reformed lion, eat straw like the ox, or at least the moral equivalent of straw.

But ought we to go further? Suppose that we could arrange the gradual extinction of carnivorous species, replacing them with new herbivorous ones. Or suppose that we could intervene genetically, so that currently carnivorous species would gradually evolve into herbivorous ones, thereby fulfilling Isaiah’s prophecy. If we could bring about the end of predation by one or the other of these means at little cost to ourselves, ought we to do it?

I concede, of course, that it would be unwise to attempt any such change given the current state of our scientific understanding. Our ignorance of the potential ramifications of our interventions in the natural world remains profound. Efforts to eliminate certain species and create new ones would have many unforeseeable and potentially catastrophic effects..

Perhaps one of the more benign scenarios is that action to reduce predation would create a Malthusian dystopia in the animal world, with higher birth rates among herbivores, overcrowding, and insufficient resources to sustain the larger populations. Instead of being killed quickly by predators, the members of species that once were prey would die slowly, painfully, and in greater numbers from starvation and disease.

Yet our relentless efforts to increase individual wealth and power are already causing massive, precipitate changes in the natural world. Many thousands of animal species either have been or are being driven to extinction as a side effect of our activities. Knowing this, we have thus far been largely unwilling even to moderate our rapacity to mitigate these effects. If, however, we were to become more amenable to exercising restraint, it is conceivable that we could do so in a selective manner, favoring the survival of some species over others. The question might then arise whether to modify our activities in ways that would favor the survival of herbivorous rather than carnivorous species.

At a minimum, we ought to be clear in advance about the values that should guide such choices if they ever arise, or if our scientific knowledge ever advances to a point at which we could seek to eliminate, alter, or replace certain species with a high degree of confidence in our predictions about the short- and long-term effects of our action. Rather than continuing to collide with the natural world with reckless indifference, we should prepare ourselves now to be able to act wisely and deliberately when the range of our choices eventually expands.

The suggestion that we consider whether and how we might exercise control over the prospects of different animal species, perhaps eventually selecting some for extinction and others for survival in accordance with our moral values, will undoubtedly strike most people as an instance of potentially tragic hubris, presumptuousness on a cosmic scale. The accusation most likely to be heard is that we would be “playing God,” impiously usurping prerogatives that belong to the deity alone. This has been a familiar refrain in the many instances in which devotees of one religion or another have sought to obstruct attempts to mitigate human suffering by, for example, introducing new medicines or medical practices, permitting and even facilitating suicide, legalizing a constrained practice of euthanasia, and so on. So it would be surprising if this same claim were not brought into service in opposition to the reduction of suffering among animals as well. Yet there are at least two good replies to it.

One is that it singles out deliberate, morally-motivated action for special condemnation, while implicitly sanctioning morally neutral action that foreseeably has the same effects, as long as those effects are not intended. One plays God, for example, if one administers a lethal injection to a patient at her own request in order to end her agony, but not if one gives her a largely ineffective analgesic only to mitigate the agony, though knowing that it will kill her as a side effect. But it is hard to believe that any self-respecting deity would be impressed by the distinction. If the first act encroaches on divine prerogatives, the second does as well.

The second response to the accusation of playing God is simple and decisive. It is that there is no deity whose prerogatives we might usurp. To the extent that these matters are up to anyone, they are up to us alone. Since it is too late to prevent human action from affecting the prospects for survival of many animal species, we ought to guide and control the effects of our action to the greatest extent we can in order to bring about the morally best, or least bad, outcomes that remain possible.

Another equally unpersuasive objection to the suggestion that we ought to eliminate carnivorism if we could do so without major ecological disruption is that this would be “against Nature.” This slogan also has a long history of deployment in crusades to ensure that human cultures remain primitive. And like the appeal to the sovereignty of a deity, it too presupposes an indefensible metaphysics. Nature is not a purposive agent, much less a wise one. There is no reason to suppose that a species has special sanctity simply because it arose in the natural process of evolution.

Many people believe that what happens among animals in the wild is not our responsibility, and indeed that what they do among themselves is none of our business. They have their own forms of life, quite different from our own, and we have no right to intrude upon them or to impose our anthropocentric values on them.

There is an element of truth in this view, which is that our moral reason to prevent harm for which we would not be responsible is weaker than our reason not to cause harm. Our primary duty with respect to animals is therefore to stop tormenting and killing them as a means of satisfying our desire to taste certain flavors or to decorate our bodies in certain ways. But if suffering is bad for animals when we cause it, it is also bad for them when other animals cause it. That suffering is bad for those who experience it is not a human prejudice; nor is an effort to prevent wild animals from suffering a moralistic attempt to police the behavior of other animals. Even if we are not morally required to prevent suffering among animals in the wild for which we are not responsible, we do have a moral reason to prevent it, just as we have a general moral reason to prevent suffering among human beings that is independent both of the cause of the suffering and of our relation to the victims. The main constraint on the permissibility of acting on our reason to prevent suffering is that our action should not cause bad effects that would be worse than those we would prevent.

That is the central issue raised by whether we ought to try to eliminate carnivorism. Because the elimination of carnivorism would require the extinction of carnivorous species, or at least their radical genetic alteration, which might be equivalent or tantamount to extinction, it might well be that the losses in value would outweigh any putative gains. Not only are most or all animal species of some instrumental value, but it is also arguable that all species have intrinsic value. As Ronald Dworkin has observed, “we tend to treat distinct animal species (though not individual animals) as sacred. We think it very important, and worth a considerable economic expense, to protect endangered species from destruction.” When Dworkin says that animal species are sacred, he means that their existence is good in a way that need not be good for anyone; nor is it good in the sense that it would be better if there were more species, so that we would have reason to create new ones if we could. “Few people,” he notes, “believe the world would be worse if there had always been fewer species of birds, and few would think it important to engineer new bird species if that were possible. What we believe important is not that there be any particular number of species but that a species that now exists not be extinguished by us.”

The intrinsic value of individual species is thus quite distinct from the value of species diversity. It also seems to follow from Dworkin’s claims that the loss involved in the extinction of an existing species cannot be compensated for, either fully or perhaps even partially, by the coming-into-existence of a new species.

The basic issue, then, seems to be a conflict between values: prevention of suffering and preservation of animal species. It is relatively uncontroversial that suffering is intrinsically bad for those who experience it, even if occasionally it is also instrumentally good for them, as when it has the purifying, redemptive effects that Dostoyevsky’s characters so often crave. Nor is it controversial that the extinction of an animal species is normally instrumentally bad. It is bad for the individual members who die and bad for other individuals and species that depended on the existence of the species for their own well-being or survival. Yet the extinction of an animal species is not necessarily bad for its individual members. (To indulge in science fiction, suppose that a chemical might be introduced into their food supply that would induce sterility but also extend their longevity.) And the extinction of a carnivorous species could be instrumentally good for all those animals that would otherwise have been its prey. That simple fact is precisely what prompts the question whether it would be good if carnivorous species were to become extinct.

The conflict, therefore, must be between preventing suffering and respecting the alleged sacredness — or, as I would phrase it, the impersonal value — of carnivorous species. Again, the claim that suffering is bad for those who experience it and thus ought in general to be prevented when possible cannot be seriously doubted. Yet the idea that individual animal species have value in themselves is less obvious. What, after all, are species? According to Darwin, they “are merely artificial combinations made for convenience.” They are collections of individuals distinguished by biologists that shade into one another over time and sometimes blur together even among contemporaneous individuals, as in the case of ring species. There are no universally agreed criteria for their individuation. In practice, the most commonly invoked criterion is the capacity for interbreeding, yet this is well known to be imperfect and to entail intransitivities of classification when applied to ring species. Nor has it ever been satisfactorily explained why a special sort of value should inhere in a collection of individuals simply by virtue of their ability to produce fertile offspring. If it is good, as I think it is, that animal life should continue, then it is instrumentally good that some animals can breed with one another. But I can see no reason to suppose that donkeys, as a group, have a special impersonal value that mules lack.

Even if animal species did have impersonal value, it would not follow that they were irreplaceable. Since animals first appeared on earth, an indefinite number of species have become extinct while an indefinite number of new species have arisen. If the appearance of new species cannot make up for the extinction of others, and if the earth could not simultaneously sustain all the species that have ever existed, it seems that it would have been better if the earliest species had never become extinct, with the consequence that the later ones would never have existed. But few of us, with our high regard for our own species, are likely to embrace that implication.

Here, then, is where matters stand thus far. It would be good to prevent the vast suffering and countless violent deaths caused by predation. There is therefore one reason to think that it would be instrumentally good if predatory animal species were to become extinct and be replaced by new herbivorous species, provided that this could occur without ecological upheaval involving more harm than would be prevented by the end of predation. The claim that existing animal species are sacred or irreplaceable is subverted by the moral irrelevance of the criteria for individuating animal species. I am therefore inclined to embrace the heretical conclusion that we have reason to desire the extinction of all carnivorous species, and I await the usual fate of heretics when this article is opened to comment.

68 comments to The Meat Eaters

  • abdalhaq

    As a strict vegetarian, I think I can understand some of the emotional underpinnings of Dr. McMahan’s argument. As a scientist, I have to say that ecologically this would be a terrible, terrible idea. I think that other people will probably make that point as well, so I won’t belabor it.

    There are a couple of issues with the argument itself, though, that I’d like to mention. The first is that the concept of “predation” is complicated. Are mosquitoes predators? Is coronavirus a predator? Parasitism, mutualism, scavenging — there is a long list of animal behaviors that somewhat muddy the waters. The basic issue is that “predation” is an abstract term, invented for convenience of discussion. The empiric realities are more difficult to pin down.

    The thrust of the argument, though, seems to be that we should eliminate predation because it is a source of animal misery. While we are indulging in science fiction: Wouldn’t it be just as good to eliminate nociception? Carrying the argument a step further, if ending all animal suffering is really our goal, shouldn’t we then simply take the initiative of painlessly eliminating all animal life?

    • Kishore Asthana

      Indeed, reduction in suffering is a good thing. However, to extend the argument, what about the feelings of the plants? Do they not suffer pain when they are harvested? In fact, studies have shown that they do. Just because we cannot understand their frame of reference is no reason to ignore their pain. Should we all then stop eating plants and vegetables?

      Killing to survive is not against animal nature. Inflicting undue pain is. No animal except homo sapiens will inflict pain on another just for fun or greed. Often we inflict pain for fun. Sometimes we inflict pain out of sheer greed, even when we do not kill the animal concerned – as we see in industrial size hatcheries which treat the egg laying chicken abysmally.

      No, vegetarianism is not the answer. Compassionate treatment of all living things is.

      • Ben

        Do you have a citation for the claim that plants suffer? Given that they don’t have neurons, much less a complex neural system, that seems pretty doubtful.

  • March 12

    Your essay gets failing marks in biology, and it overestimates human potential for control of the physical world. We may have placed ourselves at the top of the food chain through ingenious use of tools, but our cognitive gift is not greater than the physical world’s balancing forces. So far, all we have achieved in our short but destructive evolutionary cycle is to disrupt natural balance in a self-destructive race.

    On the other hand, if your essay is just a dialectical exercise, its arguments are not always logical. “The extinction of an individual species…is bad for the individual members who die and bad for other individuals and species that depended on the existence of the species for their own well-being or survival,” Yet you are considering the option of engineering the extinction of certain species, regardless of the “badness” of such an option. We would neuter all individuals in that species, which would allow all its members to die of old age, in the process saving other individuals in the prey species from “immoral” suffering.

    Your thesis is premised on a Western concept of suffering, which you assume happens when prey are attacked by predators. As you well admit, that is an anthropocentric view, and you attempt to counter this interpretation by means of unrelated arguments: “our moral reason to prevent harm for which we would not be responsible is weaker than our reason not to cause harm.” But it would be OK to cause harm to plants? They are living things as well. Where do you draw the line of human “duty” or moral reason to prevent suffering? By the way, please define “suffering.” Is it equal to destruction?

    Biology is above and beyond human morality. There is beauty and balance in the food chain. On the other hand, the human tendency to upset that balance could be described as immoral. All the more immoral for its long-term self-destructive effects. Isn’t the meaning of morality, after all, that which is of long-term benefit to our human group? The option to engineer natural evolution is so immoral that it is offensive.

    Some members of our human species might be too proud to recognize that we, as well as all other living species, are controlled by DNA, which evolves and manifests itself in response to forces in our physical world, some more immediate than others. And others might be too narrow minded to realize that a greater force acts as origin and end of all life.

  • Jeff, you come to the pregnant conclusion that we have reason to desire the extinction of all carnivorous animal species but it seems there’s a less provocative conclusion you could have drawn, that we explore the possibility of transforming into vegans all otherwise carnivorous species. Or, even less dramatically, ovo-lacto vegetarian transformation. Assume a future in which our biological sciences, and especially ecology, have matured well beyond their current infant states; in which our suite of selective wild animal breeding techniques have outstripped in efficiency and effectiveness those currently on offer; in which most humans have adopted largely peaceful ways of life, forswearing violence against other humans and nonhuman animals; and in which genetic engineering technologies have similarly become powerful and subtle. Throw in a little luck, and you might be forgiven for thinking we could produce ovo-lacto veggie lions, no? By hypothesis, such lions would not be today’s lions, a fact to be regretted. But they might look like like today’s lions, a fact to be celebrated. And–taking away the predation–they might largely behave like today’s lions. All else equal, wouldn’t a world with such creatures in it be better than one without?

  • JJ

    As I read it we are talking talking here about the MORALITY of hypothetical actions and not the practicality of the approach.
    With that in mind;

    “But if suffering is bad for animals when we cause it, it is also bad for them when other animals cause it.”

    A is bad when caused by B.
    Therefore, A is bad when caused by C. ???

    This is the hinge of the argument, and it remains unjustified. Until you demonstrate that “suffering” is, by definition, immoral then you are open to what follows:

    The problem with harming animals isn’t with the suffering it creates in the world. There is no magical utilitarian scale which crosses the line at suffering amount X.

    The moral problem with creating suffering is with the creator OF the suffering. We have moral duties we ought impose on ourselves for our own moral well-being. In creating needless suffering in the world we make ourselves immoral, not the world around us.

    Focusing on the “immorality” of agent-less action is like trying to debate the morality of a $100 bill.

    You could use the currency to feed the poor or exploit his neighbor. Do you then describe the currency as “evil” or “good” or should you rightfully attribute those traits to the spender?

    Actions are the CURRENCY of morality only. The actor, the moral agent, is the only party who can be rightfully attributed traits of morality. Other animals, not possessing any moral compass (that we know of), are necessarily removed from moral agency. They, and their actions are of no real moral consequence.

    We might have certain visceral reactions to their ways and might find them barbaric and uncivilized. But the fact remains that they are not moral agents and therefore are incapable of being justifiably labeled with attributes of morality.

    Unless you are willing to redefine morality so as to create classes of things such as “evil babies,” “moral hurricanes,” “nasty rainbows,” or “good trees” then you shouldn’t attempt to label the “immoral carnivores.” Such logic only leads to a moral confusion and serves to erode the real power of morality; which is the responsibility it demands of us who can recognize it.

  • Don Albers

    Professor McMahan, you may be an accomplished philosopher,but you evidently know little about agriculture. Any farmer, factory or not, would not be in business long inflicting “a lifetime of misery and torment” on their animals.

  • Some commentators here seem to speak as if McMahan is missing out on some obvious scientific truth, something he should have learned in an introductory ecology or biology course. I don’t see what scientific truth conflicts with this claim: To some extent, it would be desirable to eliminate carnivorous species, and if we could do so without sufficiently bad consequences, it might be a good idea. I see that it is hard to imagine a way to do this without very bad consequences, but is there some evidence that conclusively shows that this will always be impossible, regardless of future technological and scientific developments? Perhaps it is unlikely that this would ever be possible, but that doesn’t show that McMahan is wrong. Or is McMahan just missing out on the obvious, purely scientific, fact that wild animal suffering is in no way undesirable?

    Perhaps the problem is that McMahan is being uncharitably interpreted, as if he thinks we should start doing this next week.

    • Nick,
      Several of the first posters highlighted some of the empirical (i.e. biological) issues in defining ‘predation,’ and in the vast gulf between McMahan’s scenario and the current state of the biological sciences. While a lot of philosophy can have a legitimate basis in a priori arguments, as you seem to be suggesting, to me it seems that by using these terms and ideas such as a ‘predator’, or an ‘animal’ (not to mention the big, big unknown of ‘suffering’) one must take into account how these words are interpreted and understood (in this case by various empirical sciences) in the present day. If not, to my eyes one is committing a linguistic fallacy, and via this linguistic error ones philosophical argument is weakened.

      Without a more rigorous examination of what ‘suffering’ (animal or human) really is, and of what a ‘carnivorous species’ is, I see no valid claims in this article for as to why the elimination of these particular species would be of any benefit or harm.

      • Ben

        I disagree. The definition of pain (or any qualia, for that matter) is a very complex one, and I think it would be massively outside the scope for him to attempt to discuss it beyond the common sense “what you feel when you get stabbed with a knife”.

        His simple statement is just that it feels “bad” for an animal to be eaten alive. How can we know this? Well, I know that it would feel bad for me to be eaten alive, and I know that the same neural structures (nocicepters) which cause this badness also exist in almost all vertebrates (and probably other phyla, although this is less certain).

        The most scientifically illiterate person can tell me that they wouldn’t want to get stabbed with a knife. The qualitative experience of pain does not require any understanding of why it happens.

        Are structures beyond nociceptors capable of giving rise to pain? Probably. Are there painful interactions which we wouldn’t classify as “predation?” Undoubtedly. But he is not claiming that universal veganism is the only ethical change. He’s just claiming that it’s one (currently highly implausible) change, which would be ethically desirable.

  • Susan Gillespie

    If you’re going to take the trouble to quote the Bible, then at least acknowledge that what Isaiah was describing pointed both backwards AND forwards, to a return to the original creation in which predation did not occur.
    The premise, then, is that animal suffering was not the intention of God, and is attributable to “the Fall” for which humanity is culpable. From that perspective, humanity needs humility, which is surely lacking in this thought experiment!
    Other commenters before me have done a better job of describing the response humulity makes to the premises of your argument.

  • Stephen H. Webb

    In my book, On God and Dogs (Oxford University Press, 1998), I defended the idea that the Bible favors domesticated animals over wild animals due to the presumption that peace is always better than violence, and I further argued that the Bible envisions domesticated animals as, in some sense, the future of all animals. I concluded my book with several practical suggestions, including the idea that we should do nothing to promote or enhance violence in nature and that, in fact, it is morally acceptable to work toward the future that the Bible envisions (that is, to work toward a future where violence in nature will be diminished or minimized). The fact is that our control of nature is increasing every day, which puts these kinds of moral questions on the table in an unavoidable way. I am grateful for Jeff McMahan’s essay and appreciate the risk he took in stating what should be obvious: if we have the power to direct evolution to some degree, then we need to think about what direction we want evolution to go.

  • Brian Hoffman

    As a physician and scientist, I suggest that Dr. McMahan’s essay demonstrates a naivte commonly seem when philosophers attempt to graft an abstract ideal onto the practical dynamics of the real world. The argument, as Mr. Beckstead distilled is, states that “it would be desirable to eliminate carnivorous species, … if we could do so without sufficiently bad consequences.” This is as innocent a position as to fantasize that it would be desirable to produce pharmaceuticals without the potential for adverse reactions. Taking the quite debatable concept that all suffering is bad and offering a practical application such as species modification on the scale suggested is nothing short of eugenics, another moral negative.

    Imposing human values on the laws of nature inevitable leads to trouble, and the author himself admits the potential for disastrous unforeseen consequences, although he remains undeterred by those possibilities. Witness the atomic bomb as an extreme example. As another more germaine one, try to imagine this planet were we to rid ourselves of the “evil” of death; do we have the resources to support immortality? Morality is a human invention, established eons after the laws of nature evolved an order of things which was working beautifully before we got here, and in ways that we are just beginning to understand. To determine what nature wants, first look there. I quote from an essay found at, a web site with which I have no affiliation:

    “In areas where wolves are absent, ungulate populations such as elk, deer, and moose
    tend to increase dramatically17 leading to declines in native plant species as well as the
    general degradation of forests and ecosystems.18 A series of studies has documented
    excessive overbrowsing by elk and moose in key riparian habitat including cottonwoods,
    willows, and aspens when wolves are absent.19 In areas where wolves have returned,
    ungulates are reduced (by predation) and more vigilant and active (fear of predation),
    which takes browsing pressure off streamside trees and shrubs, allowing them to grow.
    This “landscape of fear” affects a prey animal’s behavior in food acquisition and thus
    modifies plant communities.20 With the return of riparian habitat, beavers and many bird
    species are supported.21 When woody species grow, expand in canopy cover, and
    increase in their spatial distribution, other benefits accrue, such as improved floodplain
    functioning, channel stabilization, increased shading, improved food web support, larger
    beaver populations, and an overall increase in biodiversity.22” []

    The philosophical exercise put forward by Dr. McMahan is an interesting thought experiment, but the essay’s language takes the dangerous and irresponsible step of offering support for a physical experiment.

    A final word: to preemptively state “I await the usual fate of heretics when this article is opened to comment,” neither supports your position nor invalidates rebuttals like mine and others outlined here.

  • Austin Hunt

    What of animal suffering that is not brought about by predation? In my own backyard there are several colonies of vegetarian ants that fight amongst each other, and if you’ve never seen what happens when two ant nests decide to kill each other you may not believe the amount of “suffering” that goes on. Limbs ripped off, bodies crushed, deaths by the hundreds etc. etc. and the bodies are never eaten. Should we eliminate them? Modify the queens to live in peace with each other? Situations like this happen billions of times each day over the entire world and occures in everything from ants to male deer that kill each other over females to Cape Buffalo that kill people simply for being in their territory. Carnivores generally go for the quick, painless kill because it’s the safest thing for them to do; not a drawn out “eat him while he’s alive” slaughter you seem to think it is. Perhapse, sir, you would do well to look at nature itself and not use such an infantile, sterotypical view of nature as the basis for your arguments. If you did you might realize that the color of nature is not green at all, it’s blood red. The only way to change it would be to eliminate nature alltogether.

  • Oscar Horta

    The structure of the main argument of the paper is quite simple. It’s this. Suppose there’s significant harm occurring. We can’t stop it, though who knows, maybe we could at some point. Should we do it?

    Most responses to this in this case simply point out that we can’t stop it. But, as Nick Beckstead rightly points out, the paper already ackowledges this. The paper makes it perfectly clear that intervention in nature for the sake of animals would be (or is) a good thing provided that the have the necessary scientific understanding required for it.

    JJ also gets this right, though his criticism fails because he doesn’t distinguish “right” and “good”. One doesn’t need to claim that, say, famines are “evil” to accept that they are bad things we should try to stop from occurring.

    The way to challenge the argument is one that Jeff McMahan anticipates in his paper, which is to assume that there are things that are more valuable than the wellbeing of animals, such as the existence of species and natural processes per se (not in virtue of their consequences). However, we must note that we do not accept such arguments when human wellbeing is involved. Nobody argues, when it comes to saving humans from suffering from natural causes, that the badness of suffering is debatable. This is the main point: one has to either show how can it be that speciesism is acceptable, accept that humans suffer a fate similar to that of nonhuman animals, or accept the soundness of the view McMahan has presented here.

    Of course, another way to oppose McMahan’s point would be to deny that nature is the kind of hell he describes, but this would be wrong. Nature really is a place in which suffering vastly outweighs pleasure or other values (on this see Ng’s “Towards welfare biology: Evolutionary economics of animal consciousness and suffering” or Dawrst’s “The Predominance of Wild-Animal Suff ering over Happiness: An Open Problem“.

    • Peter

      By the same logic, could one not then argue that we should genetically engineer humanity FIRST to eliminate human suffering.

  • James

    You draw your arguments from an interesting range of sources channelling both Darwinian theory and Judeo-Christian theology. An uncomfortable marriage of ideas.

    Isaiah’s prophecy may have been the biblical proclamation of evolution given their understanding of animal behavior at the time.

    Your piece though ignores MANY instances where controlled destruction of animal species have been met with abject failure and enormous destruction to the world as we known not to mention extreme suffering to many other animals. You speak mainly to the elimination of mammalian carnivores without considering the lower species. Animals that eat insects cause suffering to the individual insect however the explosion of insect populations as seen in the Great Sparrow Campaign. The resulting Great Chinese Famine speaks to the ludicrous nature of your position.

    Your essay contains sound logic and a string of reasoning but ignores historical context in attempts to reduce carnivore populations.

  • A few comments: 1) It seems the proper focus for the discussion should be “predation” not “carnivory” – vultures, for example, are harmlessly carnivorous. In fact some plants are – arguably – both predacious and carnivorous – the Venus fly trap, for example. (This is an issue that I have not seen addressed by “vegetarians”?) Windfall and carrion would seem to be the least “harmful” of diets [Leaving aside Jainist concerns for the microscopic?) Saturday Night Live in 1977 did a pointed skit based on the notion of a “Natural Causes Restaurant” [SEE: ] 2) evolution is not teleological / purposive — arguments grounded in such notions are essentially faith-based / belief-based and deserve respect/ evaluation as such 3) a very clear lesson of the global analysis of climate change is that there are now no “pristine parts” of nature that are independent of human impact – the problem (and Dr. McMahan addresses this) is whether we can be more consciously discrete about our actions and their consequences in nature. Sadly, our track record is very poor whether considering human ecological interventions – or eugenics. (And essentially McMahan’s essay addresses eugenics. Richard Lewontin has written extensively on these neo-eugenicist fallacies of contemporary genomics.)

  • Lori Gruen

    Jeff’s heretic imagination is always provocative and the proposal to eliminate predators (either through extinction or genetic modification) in order to minimize the suffering they cause their prey is no exception. Fortunately, as Jeff acknowledges, given our current lack of knowledge and the history of our bungling when we attempt to interfere in the workings of nature, the proposal is not something we need to act on. But it does raise important questions of value.

    As Jeff puts it the values in conflict are between the suffering caused by predation and the loss of existing animals species. He argues that “the claim that existing animal species are sacred or irreplaceable is subverted by the moral irrelevance of the criteria for individuating animal species.” And I agree with him on this, however, there may be other values at stake.

    There does seem to be a strong intuition about killing an animal whose species is on the verge of extinction that makes the killing of that individual seem especially objectionable. I get distraught when I hear about any animal being painfully slaughtered, but I became incensed when I hear, for example, that one of maybe a couple hundred remaining Bengal tigers was killed to use his organs as an alleged aphrodisiac. Why is that senseless slaughter more distressing than the senseless slaughter of a member of a less endangered species? I don’t think its because I am attached to a morally irrelevant biological convention. It may be that killing the last individuals of a species represents a different sort of loss.

    Perhaps the value of species doesn’t reduce simply to the well-being of each individual member of the current configuration of that species, but that value doesn’t transcend the members either. There is value in the relations that the existence of the collective allows to be realized. The well-being of most animals, particularly social animals, relies centrally on their ability to develop relations with others of their kind, to learn species-typical behaviors, and to develop specific cultures. Individual flourishing, in humans and other animals, crucially depends on a sustaining and sustainable context much larger than the individual, and perhaps therein lies the value of species. When a species goes extinct, what is lost are the particular individuals and the whole community’s way of being, even predatory being, that was constitutive of allowing those individuals to live good lives, when they did.

    Of course, not all ways of being ought to be preserved, and perhaps predatory ways of being shouldn’t, as Jeff suggests. But there may be more of value that is lost in the hypothetical world in which we decide to eliminate predators that is worth reflecting on.

  • Brian Leiter

    You write: “Our factory farms, which supply most of the meat and eggs consumed in developed societies, inflict a lifetime of misery and torment on our prey, in contrast to the relatively brief agonies endured by the victims of predators in the wild. From the moral perspective, there is nothing that can plausibly be said in defense of this practice.”

    I take it Kant thought animals had no moral standing, so from the Kantian moral perspective, there is nothing objectionable about factory farming. Do you believe, therefore, that “the moral perspective” to which you refer can not include Kantian ethics? And, if so, does this mean the argument against factory farming also presupposes some form of moral realism, according to which hedonic considerations are necessarily morally significant, and that any moral system that excludes them (such as Kant’s) is false?

  • Ellie Maldonado

    We need not take an anthropocentric view to understand that nonhuman animals who fall prey to others suffer. Conscious living beings have a personal interest in surviving. Whether or not they understand death (and some obviously do), or they feel physical pain, they are aware of being caught, and of succumbing to what they most feared. Life is personal and individual, not a collection of species.

    I don’t watch programs that film predation because I find them upsetting, but carnivores have no choice if they are to survive, which is why it’s not immoral. Neither do I agree that nonhumans have no morals or souls. Social animals have a sense empathy and of what’s right and wrong within their groups; and if humans have souls, there’s no reason to think other animals don’t. That’s convenient belief for humans who exploit them.

    I think nonhuman animals have a right to live on their own terms, rather than under human dominion. They can control their own populations in relation to available food. Despite what hunters claim, when they are killed by humans or other animals, more food is available for survivors, which in turn increases their reproduction.

    That said, if there were no predatory animals, included humans, the habitat of other animals would have to be limited, since they reproduce to the extent it supports them. For their sake, this should be done *now, but govenment agencies are in bed with hunters and the millions of dollars hunting brings in. Often hunters kill off natural predators, and then claim other animals are overpopulated, and “need to be killed” to prevent starvation. Human hunters kill hundreds of thousands of free-living animals each year, far more than natural predators who have no other choice. Most of us can choose to live without killing. We’re morally responsible for causing gratuitous harm.

    If any nonhumans would benefit from not existing, it’s domesticated animals, who are bred to be killed for food or other “acceptable purposes”, or are simply dependent on humans who are happy to use them, yet don’t protect their most basic interests.

  • N. Ann Davis

    I agree with JM that humans should decrease their consumption of animals, and ideally cease eating them altogether. But that is not likely to be possible logistically for some time (if it ever is). In the interim, it is surely morally incumbent on those of us who are affluent enough to be able to exercise choice to put an end to factory farming and other patently inhumane practices that inflict short miserable lives and horrible deaths on animals that are raised for food.

    I think that nothing follows from this about the possibility, wisdom, or morality of interventions that would putatively result in fewer animals savaging and eating each other, either because there has been an alteration in the behavior of extant species or because there has been a hastening of the extinction of carnivorous species and inculcation of ‘replacement’ herbivores.

    Nothing follows, and there is not a lot that can be said in favor of trying to persuade people to embrace such an enterprise. We might engage in an exercise in which we try to imagine what ‘Herb world’ might have been like—viz., a world in which evolution had taken a radically different path, and populated this planet only with non-carnivorous species. But even if we can invent such a world in our imagination, there is no reason to think that our imaginings really represent possible scenarios for us, or for this world.

    I will leave it to those with greater facility in describing the workings of ecology and evolutionary biology to explain in detail why JM’s proposal is so far removed from ecological and evolutionary empirical reality as to be worth considering only as a thought experiment, a rather sweet ‘Modest Proposal.’ Still, it is worth making it clear that, while in the optative mode we can wish that animals did not inflict suffering on each other (though they are not to be indicted for inflicting UNNECESSARY suffering on each other; that honor goes to humans), and wish that humans were not vulnerable to diseases that shorten life and diminish its pleasures, the possibility of our wishing for such things does not constitute grounds for believing that what we are wishing for is truly intelligible, implementable, or good all things considered. We can wish for these things, and intelligibly imagine that our world could become one in which there were less suffering experienced—e.g., that goats and gazelles that were being killed and eaten by carnivores evolved to secrete a natural anesthetic that enabled them to enter a trace-like state when they were being torn limb from limb, and thus not aware of what was happening to them. We can wish that diseases that shorten human life and its enjoyment were less horrible, less protracted, less frequent, and less likely to occur early in life and produce examples of effectively exercised control in this domain. But the fact that we can wish for such things, and imagine some instances in which (we think) they could come to pass does not mean that our imaginings truly represent coherent, implementable, or overall good global possibilities.

    Arguing that it would be a better world if HUMANS did not engage in factory farming and did not eat animals is, of course, something that many of us do believe represents a coherent, implementable, and good path. If it were taken, there is reason to think that it would result in a world that is clearly a better world for us, for the planet, and for many animals (though one must bear in mind Leonard Woolf’s remark to the effect that there would BE no pigs ‘if all the world were Jewish’). There is reason to think that attempts to get humans to be less barbarous in our eating practices have a pretty good chance of changing the behavior of a significant number of humans. If so, isn’t there more to be said for encouraging philosophers to continue to devote their energies to underscoring these points than to engaging in imaginative exercises that involve rewriting the ecological substrate of the whole planet, and ignoring the biological, ecological, and evolutionary hard facts?

    • Ellie Maldonado

      As an animal advocate, I appreciate the interest in sparing nonhuman animals from suffering, but it’s not in their interest for us to believe that “free-range”, “traditional”, “certified humane”, “compassionate” or “family farms” do that. Farm animals are still debeaked, dehorned, budded, and castrated without anesthesia. Farming depends on the artifical insemination of female animals, and just as surely in taking their young.

      For cows and other farm animals who see their babies, separation is extremely traumatic for both. Male animals are usually killed within 2-3 months, if not at birth, as male chicks are. Breeding and egg laying animals are allowed to live as long as they can produce, which is usually about 2 for hens and 3-5 years for cows and others animals, a fraction of their natural lifespans.

      So “humane” farms are really not any better. There also isn’t enough land for “free-range” farms. What’s used is taken from the habitat of free-living animals. Even if people think that’s ok, land is still limited.

    • Mark Reid

      Nancy, I agree that “there is reason to think that attempts to get humans to be less barbarous in our eating practices have a pretty good chance of changing the behavior of a significant number of humans” and that we should do so. But does that diminish the value of “engaging in [Jeff’s] imaginative exercises”? Why can’t we do both?

      Also, it may not be a purely imaginative exercise. We are inextricably part of ecosystems and certain choices, even forced choices, that we must make are likely to be (if they have not already) between two kinds of species, one kind that is more predatory and carnivorous than the other. Level of predation of a species seems a valid a property. We choose between favoring one species over another based on other properties, e.g., beauty, harm to humans, what we see as harm to the environment as in the case of native versus invasive species, and there seems no obvious reason not to prefer species over others based on the properties of predation or carnivory.

      Admittedly, this does not defend Jeff’s full-fledged proposal, but doesn’t it show that there is a value in the imaginative exercise that is the first time of asking the question?

  • McMahan’s article is challenging but rewarding. I take up the merits of his argument in greater detail here:

  • James McClintock

    The article makes several assumptions that substantially weaken the conclusion. We cannot know what any animal experiences when preyed upon. We can only know what we would expect to feel and experience. The equating of suffering and bad is presumptuous. These are human concepts whose application to animals is unknown and unknowable. I agree that humans should consume less animal products, for a whole host of reasons. However, to eliminate species because we deem their behavior “bad” because their life causes “suffering” to other animals would only cause greater disruption to life on this planet and may indeed be profoundly wrong because of reasons we have not yet discovered or understand.

    • Ellie Maldonado

      We know from observation that animals who become prey run from natural predators. Clearly, they want to survive and not be harmed. There’s no doubt that vertebrates and some invertebrates can feel pain. Still, I think we should control ourselves, rather than other animals.

  • Victor Tadros

    Here’s the argument if I understand it.

    1) The suffering of animals is bad
    2) We have reason to prevent the bad if we can
    3) We can prevent the suffering of animals by preventing the cause of their suffering to come into existence.
    3) Many carniverous animals (vultures, for example, excluded – by the way I like the fact that the essay rectifies defamation of the vulture…their pleasure is all good and causes no harm!) cause the suffering of animals
    4) If we could prevent new carniverous animals coming into existence we have reason to do so.
    5) That reason might be defeated by reasons against doing so, including the impersonal value of carniverous animals (looking at tigers makes children happy, for example), side-effect harms and the risk to the eco-system etc.

    Few sensible people (unlike Brian Leiter I don’t think that Kant was sensible, at least about animals) will reject 1 and 2.

    One question about 3) removing the cause of something does not prevent that thing occurring. The thing may be overdetermined. Would the deaths of animals involve less suffering were they not killed by carniverous animals? Their suffering would be different – it would not involve terror – but it might be longer and worse. Terror might be worse for humans than it is for animals. Animals, of course, might have other interests in not being killed, such as an interest in longer life. I think that Jeff believes that they do have an interest in longer life (I vaguely remember reading this in the Ethics of Killing), but that is contentious.

    4) needs refining. The fact that carniverous animals causes the suffering of other animals does not provide a reason to prevent them from coming into existence, only a reason to prevent them from killing other animals. We might find less radical ways to do this (modifying them so that they have more vulture-like qualities would be one way).

    5) seems to me true. But it may be that the reason in 4) is easily defeated. Whether this is so depends on the quality of the impersonal value. The somewhat puzzling, but somewhat intuitive, Dworkin thought that Jeff challenges needs reworking in this context. First, what is the impersonal value of the existence of carniverous creatures as a whole? Second, if we are mainly concerned with preventing extinction of a species, we could rework Jeff’s proposal and simply radically reduce the number of each carniverous species whilst preventing their extinction.

    Of course, all of this supposes capacities and knowledge that we lack. Jeff is getting bashed for supposing this. But if our philosphical imaginations were constrained by our actual capacities, philosophers would have made much less progress and have had much less fun.

  • Chris Desopoulos

    My question is simply this. Why would you want to mold the world in such a way? Leave aside the empirical difficulties, what have you got left when you are the ultimate creator of your world? Taken to its extreme, the suggestion of this article is to do just that… become the arbiter and creator of all species and their interactions. In other words, you’re playing God.

    I don’t care about the ethics of being God, or whether it’s possible. It offends me because in the long run it’s mere narcissism. At best, being the ultimate referee would be horribly tedious and boring. At worst, you would lose you own sense of self and collapse under the weight. Why? Because a human (or any organism for that matter) is not isolated, a human is a gestalt of relationships in action. If every agent of your relationships becomes a reflection of your own self, your own ethics, your own rules of the game, who do you become? Where’s your inter-subjectivity?

    Prof. McMahan asks why we shouldn’t mold species to our own ethic if we have the power. I answer that question with a question of my own. Do you think it’s advisable to convert the world into a hall of mirrors?

    • Victor Tadros

      Why couldn’t we fulfil Jeff’s proposals through democratic decision-making? In that case we’d have lots of intersubjectivity. Also, if we had lots of power to mould our world, intersubjectivity might lose its appeal. We’d have more fun things to do than relate to other people, which can get quite boring after a bit.

      • Chris Desopoulos

        We would have intersubjectivity within our species, perhaps, but we lose that interaction with the world at large. It comes down to a “reality check”, assuming you admit that as a possibility. Basic health can be an example of how this would break down.

        Assume we could do away with “harmful” bacteria. So then we can defecate in our immediate surroundings with no immediate feedback (stench, disease) to tell us that’s not a good idea. Ultimately, we risk poisoning ourselves — unless we add in the ability to make all toxins non-toxic. So where does this manipulation stop? What are we when we’ve finally removed all physical distinctions that we don’t agree with? I ask that quite literally, BTW… What would we be, and how would we distinguish ourselves if we remove distinctions?

        Yes, it’s a generalization to say that individuals would lose sense of self from this project. But it’s also a generalization to say that we as a species would not. Even so, how is it that intersubjectivity losing its appeal (as you propose) is fundamentally different from intersubjectivity going away? I can accept that intersubjectivity can be a pain, and a bore at times. But what else have we got? Where does your knowledge come from, if not from the “out there” banging against your skin (retinas included)? What are you if you don’t have any relationships?

        When does playing God (exercising the power to mold your world) devolve into masturbation? Is art possible without a sociopolitical context? What is philosophy if you never discuss it? And, as the Spanish say, un largo etcetera…

        As a species, what are we if we no longer have to interact with other species? Or more to the point of this article, if we can mandate all the terms of that interaction? Our superior adaptation (and history) already raises us to a dangerous isolation from other species. Are you satisfied with the results?

  • Tom Rowe

    If we allow Jeff McMahan to have as a given that there will one day be a trusted technical means to genetically engineer animals as we see fit without causing cascading and uncontrolled harm to ecosystems, other species, etc. then perhaps I may assert a path that achieves the goals Mr. McMahan sets out without the need to alter any species’ genetics.

    Nanotechnology promises (see Engines of Creation by Eric Drexler) that one day we will have the technical means to build just about anything we can design from atoms up. As an example, Drexler suggests that from some hay and dirt, a solution of nano-sized machines might produce meat. I suggest that if such “meat machines” (each producing meat appopriate to an approaching predator) were placed in wild areas of the world (on land seems more practical than at sea) that currently support various predators, most predators would learn to take meat from the free vending machine rather than hunt down meat that tries to escape.

    Providing food for animals in the wild does of course make those animals dependent on humans but they are already so – destruction of habitats, etc.

  • McMahan claims to put God to one side in his argument for the elimination of predators, but I see his brief as riddled with deity. To be fair (or “full disclosure”), I see the problem with morality itself, that is, with the “ought” form of morality. McMahan quotes Schopenhauer in support of an animal version of the Argument from Evil. (Incidentally, Darwin attributed his own atheism to the same argument in his Autobiography, as Rachels pointed out in Created from Animals.) But Schopenhauer also had this to say:

    … the concept of ought, the imperative form of ethics, applies solely to theological morality, and … outside this it loses all sense and meaning. (On the Basis of Morality, tr. E.F.J. Payne (Hackett, 1995, p. 130))

    Therefore, if McMahan’s argument were truly atheistic, it would not be trying to establish what we ought to do. (“If we could bring about the end of predation by one or the other of these means at little cost to ourselves, ought we to do it?” The point applies as well to permissibility, to which McMahan retreats by the end of the essay.)

    McMahan’s argument takes a utilitarian approach to predation. Several commentators have, like McMahan himself, already remarked on the absurdity of trying to do the relevant calculation/prediction of what the consequences of eliminating all predation would be. But more to my point would be that even if such a calculation were practicable, its imperative upshot would be … well, there wouldn’t be any. No ought from is, you know.

    I don’t deny that we can be moved by various considerations. I for one am sufficiently moved by thoughts of the plight of nonhuman animals at human hands to be a vegan in my dietary and other choices. I also try to persuade and influence others to become vegan, by informing them about industrial and even traditional farming – the cruelty to the animals and the impact of animal agriculture on the environment, including global warming — , by introducing them to delicious vegan cuisine and providing them with nutritional information, by encouraging them to read about evolutionary theory and reflect on the implications for our relation to other animals, and to become acquainted with ethological studies and otherwise get to know what other animals are really like, and by simply modeling veganism in my own behavior. But to top it off with “Therefore you ought to be a vegan like me” now strikes me (a reformed moralist) as a rhetorical move, the invocation of an implicit (and fictitious) law-giving divinity to buttress my personal preference.

    McMahan rejects God in two different ways in his essay. The first is via the aforementioned animal argument from evil. The second is as a Being Whose prerogatives we would be hubristically usurping were we to try to protect the animal world from predation. McMahan thinks he refutes the “playing God” charge not only via atheism itself but also via commonplace considerations about human interventions we all approve, such as finding cures for diseases. But I still think McMahan’s own argument contains God in the second way when it presumes to find, or at least seek, The Answer to whether the elimination of all predators would, under certain circumstances, be The Right Thing to Do, or at least Permissible, or at least Good (to invoke objective value rather than objective morality), when in fact he is talking about a human vision of an ideal world. Furthermore, that “human” vision might be quite parochial (as “experimental philosophy” has made us aware), since the image McMahan wants to make the world conform to – the value(s) he would prioritize — could well be different from other people’s and societies’. I for one favor the natural world just the way it is and think our task would be complete were we to preserve sufficient habitats for wild animals, predators and all.

    Let me reiterate that I am not advocating indifference or passivity or an end to argument or enshrining the status quo as the alternative. I just think we should call a spade a spade. Thus, let’s put aside Commandments as well as God and instead use all of our intelligence, insight, and compassion to refine our own (respective) desires and then try to implement them. This would also, I believe, foster mutual respect and tolerance among human beings, although we will no doubt continue to have deep and irresolvable differences.

    • Victor Tadros


      you suggest that it is appropriate to claim that ‘x is good’, ‘x is right’ or ‘x is permissible’ only if God exists. I don’t see how the non-existence of God makes these claims inappropriate. Also how could God’s existence could transform them into being appropriate? Wouldn’t that imply the derivation of all Oughts from one Is (the existence of God)?

  • Mark Schroeder

    The moral question in this essay is at least an interesting thought experiment. As a scientist rather than a philosopher, my personal take on philosophy is grounded much more in reality and what science tells us.

    The claim that nature is not purposeful is certainly true, but it has been built on an unfathomably large amount of trial and error. While the process almost certainly works through local optima, the generation of flawed species, it has generated systems that embody certain design principles or truths. That is a strong basis for sanctity, or at least a strong hesitance to monkey with how the world works.

    While there are a lot of concrete things to say about various proposals, I would like to take on the argument that pain is bad. If pain was really bad, animals wouldn’t feel it. It serves an extremely important instructive purpose that guides learning. While I think needless suffering is bad, the struggle between predator and prey is exactly what shapes and drives species to evolve and improve at their role within nature and the pain an animal feels is an extremely important part of this. Trying to remove pain from the mix is basically missing the whole point.

    Instead what the system needs is more “senses” not less. The human senses of empathy that help us understand and predict the world around us need to be harnessed more strongly. Presumably this sense should make us the kindest of predators. Although I think there are many farmers that are humane, I’m sure there are inhumane institutions as well. The fact our main “societal sense,” media, has horrible dynamic range and has devolved into strict entertainment is a serious problem. To the extent we do torture animals the fact it is hidden is a problem and many aspects of the problems associated with it would be mitigated greatly by a greater sensitivity to the problem through being able to see it through media.

    To speak outside of the human realm, it could be that predators being more “empathetic” of their prey would improve hunting success, by helping to understand and model the process better. It could be that domestication is a better model. I’m not that familiar with ecology and I don’t know whether there is any evidence that ecosystems optimize anything in particular. However, it is likely to me that there is some tendency to optimize the use of resources. As to the argument that we should be more conscious of our interactions with the natural world and the fact that active approaches are better than passive ones, I certainly agree.

    The problem is that figuring out where the course of nature is taking us and whether we want to simply help it along or guide it to something “better” is something well outside our current understanding. But something certainly worth considering. I would argue that this starts with focused scientific understanding of the world itself. Man is clearly evolved for a different world than the one he lives in now and is clearly shaping. Society is doomed if we don’t begin to use the power of culture to shape our desires to be in better touch and understanding of the world around us. By sheer force of numbers and power over resources we will increasingly dominate the world and we do need a vision of where to take it.

  • Mark Reid

    In this comment, I show that an important concept that is absent from McMahan’s discussion is that carnivory is a matter of degree. I agree with McMahan, but I claim that what is good about choosing less predatory species over more predatory species is not merely that the choice results in less predation but that it results less predatory minds, which is good in itself.

    On the one hand, when vegetation is scarce, some species of hare will gnaw on bones, while on the other hand, domesticated dogs may obtain all the nutrients they need from a vegan diet. In contrast, feline or weasel digestive tracts have problems digesting fiber. In nature, groups of the same species have very different diets. Killer whales, for instance, resident to the Puget Sound, live peacefully with other mammals such as seals, sea lions, and dolphins, living exclusively on a diet of fish, whereas other killer whales, referred to as “transients,” roam the open ocean and shorelines and prey on any animal whatever including seals and sea lions, which have a mental sophistication that is far greater than that of fish. (Incidentally, residents despise transients and chase them from the Sound). An aardvark kills and eats insects but it would seem that an aardvark is less predatory and carnivorous than a raccoon that eats lizards and small mammals, although both eat animals. Wolves alone or in a pack will rarely, if ever, attack or kill a human being, although they certainly are capable to do so. Although it might be a small difference, tigers are more predatory than lions, and probably because of the social nature of lions, the bonds that a human may form with a lion will protect him from being seen as a source of food. It is difficult to imagine this is the case with tigers.

    The facts may be slightly different from these. But, something along these lines is certainly true, and it follows from them that carnivory is a matter of degree on several different scales, including diet, lifestyle, the mental sophistication of a carnivore’s prey, and the degree to which a creature has a predatory mind. That carnivory is a matter of degree is an important aspect that is absent from McMahan’s discussion.

    McMahan’s thesis must be true, in part. When we are forced to choose between preserving species (or groups within species) that differ in their degree of carnivorousness, I believe the obvious answer is that, all other things being equal, we aim to preserve the species (or group) that is less carnivorous. So, for instance, between preserving resident killer whales or “transient” killer whales, I believe the correct moral choice, in fact the morally obligatory choice, is to preserve resident killer whales. (The groups may be of the same species, but I believe the answer is the same if we imagine it were a choice between two different species). An obvious reason that this choice is better is that it reduces the number of casualties and amount of suffering, especially of mentally sophisticated animals. A less obvious reason is that it reduces the number of predatory minds, which is good (just as, e.g., it would be better to reduce the number of human psychopaths than it would be to reduce the number of human nonpsychopaths).

    I believe there is something deeply disturbing in the character of some solitary predators, whether human or nonhuman, that will kill and eat about anything including humans and conspecific offspring. They have psychopathic traits and fewer capacities for moral agency than other social animals. The view that nonhuman mammals are moral agents is not shared by many, but it is gaining in popularity. Moreover, it makes sense of some of the reasons that it is good to prefer less carnivorous and predatory species over those that are more carnivorous and predatory. Humans and other advanced species such as killer whales are complex in that members and groups differ in their degree of carnivory and predation. If the same principles are applied to the human species, then we should choose against more predatory humans, such as psychopaths, cannibals, and those responsible for the factory farming of animals and the even more horrific case of the fur trade.

    • Gerardo Camilo

      Mark, that is correct. In order to have a herbivore world, you not only need to get rid of predator, you MUST also eliminate genetic variability within herbivore species for any and all traits that may lead to predation.

  • Jeff McMahan

    I am grateful for the civility and intelligence of the comments on this site. The contrast with the general tenor of the comments on The Stone is striking.

    I will offer at least a brief response to each commentator.

    Abdal Haq: I noted in my piece that I’m not advocating an effort to eliminate predatory, carnivorous species now. I agree that that would be a terrible idea. But I also noted that our understanding of ecological science is likely to advance enormously over time. And in the meantime our collective action is causing and will continue to cause many animal species to become extinct. If we can’t prevent that altogether, we may at least be able to exercise some control over which species become extinct. I’ve suggested one criterion that might guide our selections.

    The elimination of nociception might be good in some respects, but like extinction, it would be bad in others. As you know, pain alerts us that we’re being injured and that our life might be in danger.

    Kishore Asthana: There are studies that show that plants react to certain stimuli, but there are no studies that show that they experience pain, or suffer from it.

    Compassionate treatment of animals seems to me to require vegetarianism.

    March 12: My piece can’t really get a failing mark in biology because it doesn’t say anything about biology apart from quoting Darwin and citing the most frequently criterion for individuating species. The moral argument and conclusion are explicitly conditional in form: if predation could be ended without ecological upheaval…

    There is, to my knowledge, no Western concept of suffering on which my argument could be premised. I’ve traveled extensively but have never met anyone who didn’t have the same concept of suffering I have. Can you explain the features of some non-Western concept of suffering?

    What does it mean to say that biology is beyond morality? It’s part of my biology to write philosophy essays about carnivorism. It’s part of our biology to act in ways that upset what you call the “balance of the food chain.” Etc.

    Gary: I do briefly acknowledge the alternative of genetic alteration in the piece. Two points. (1) Radical genetic alteration of a species’ digestive system and behavior might, on some ways of distinguishing between species, be equivalent to the creation of a new species. (2) If genetic science advances far enough to enable us to reconfigure lions as vegans, it might enable us to create a new herbivore even more magnificent and beautiful than a lion.

    JJ: Thanks for your first point, which many readers missed.

    I agree with Oscar Horta that suffering is not immoral. But allowing it to occur when one could prevent it might be.

    Don Albers: Your point is an a priori deduction: if animals reared for consumption were miserable, farmers wouldn’t make a profit, presumably because the animals would be unhealthy as well as miserable. But the evident facts about factory farming refute that deduction.

    Nick: Thanks for correcting those misunderstandings.

    Adam Cahan: Suffering is not a “big, big, unknown” to most of us. If it is to you, you’re very fortunate.

    Ben: Thanks.

    Stephen Webb: As you know from reading my piece, I’m not a theist, but I am always happy to make common cause with theists whose hearts are in the right place. Thanks so much for your kind and eminently sensible comment.

    Brian Hoffman: “This is as innocent a position as to fantasize that it would be desirable to produce pharmaceuticals without the potential for adverse reactions.” Is it really a fantasy to suppose that someday it might be possible to produce a drug that lacked harmful side effects? And isn’t that something we should strive to do?

    Is it really debatable that suffering is intrinsically bad? I acknowledged that it can be instrumentally good.

    I also explicitly acknowledged that the disappearance of predation in an area can result in overpopulation by herbivores in that area – the same point that’s made in the lengthy passage you cite. My question was whether it would be better, if possible, if animals in the wild did not have to live continuously in what the passage you quote refers to as a “landscape of fear.” If there were a way to maintain ecological stability in an area without constant fear, suffering, and violent death, wouldn’t that be better?

    My remark about the fate of heretics wasn’t meant to be a substantive rebuttal to any objections my piece might raise. If you think it was off the mark, please read some of the comments on the NYT blog.

    Austin Hunt: I’m not sure what the “infantile, stereotypical view of nature” to which you refer actually is. You suggest that if I were to look at nature, I would see that “it’s blood red.” That view, rather than a perception of nature as an idyllic paradise, is the background assumption of my entire argument.

    Oscar: Thanks.

    James: My position is not ludicrous because I neglect to consider the possible disastrous side effects of the elimination of certain species. As I noted earlier, I explicitly note this possibility in a couple of places in the piece.

    Tom Moritz: Thanks.

    Lori: Thanks for this constructive suggestion. I think I detect two points in your penultimate paragraph. One is that the well-being of individual animals requires that they live in some sort of community. This does seem to be true of many types of animal. But the most that that claim supports is that IF a species will exist, there should be enough members that they can all have decent lives. The other point is that species are not just biological units but also have distinct forms of life that may be valuable. I accept that but think that non-predatory forms of life are better in their effects on others than predatory ones. Thus if we could choose which one of two possible species would come into existence, and each would have its own unique form of life, but one would be predatory and the other non-predatory, and if all other relevant considerations were equal, I think we ought to choose the non-predatory species.

    Brian: Christine Korsgaard has labored mightily, with considerable success as far as I can tell on the basis of my limited initiation into the mysteries of Kantian theory, to show that Kant himself was rather unimaginative in deploying the resources of his own theory to understand the nature of our duties with respect to animals. She argues that Kant’s theory actually does imply that factory farming is morally objectionable. But suppose she’s wrong and Kant was right. I would then take it as a reductio ad absurdum of his theory that it had the implication that there is nothing morally objectionable about causing suffering to billions of animals for reasons of trivial self-interest.

    Ellie Maldonado: There’s another reason why the carnivorous action of predators is not immoral, and that is that nonhuman carnivores are not morally responsible agents.

    I have no figures on this but I doubt that human hunters worldwide kill as many animals in a year as animal predators do worldwide.

    Ann: I agree that it’s far more important to work to reduce and eventually eliminate meat-eating among human beings. But I’ve gone on about that at length in other forums and wanted to say something new. I don’t think my piece ignores any biological, ecological, or evolutionary facts. It just makes a case for one course of action we ought to take if we could make the facts other than what they are now.

    Matt Hoberg: I haven’t read your piece yet but look forward to doing so.

    James McClintock: Can you explain how I can know that a human being is suffering while I can’t know whether an animal is suffering because that is “unknown and unknowable?” If you read my piece carefully you will see that I never say that the behavior of animals is “bad,” where “bad” means “wrong.” I repeat: it’s a mistake to suppose that either suffering or animal action is immoral. Our reason to prevent suffering is that suffering is intrinsically bad for those who suffer, and we have a moral reason to prevent what’s intrinsically bad from occurring when possible.

    Ellie Maldonado: I agree that we should control ourselves first. But if we can later intervene to limit animal suffering, we ought to do that as well.

    Victor: Nice summary of the argument, except that the happiness that children get from looking at tigers is part of their instrumental value, not their impersonal value.

    Your observation that reducing the number of individual carnivores without driving any species to extinction could achieve most of what I think it would be desirable to achieve is helpful. It has to be qualified, though, to take account of the point that Lori makes in her comment.

    Chris Desopoulos: I doubt that efforts to reduce the suffering of animals in the wild would entail the loss of inter-subjectivity, whatever exactly that is. Couldn’t our working together toward that goal advance our inter-subjectivity?

    A great deal of what we ought morally to do is tedious and boring. We just have to put up with it.

    Tim Rowe: Thanks, that’s an unusually creative thought. It would, of course, create the same problems that I’ve been repeatedly castigated for supposedly ignoring: uncontrolled proliferation of herbivores, depletion of vegetation, etc.

    Joel Marks: Schopenhauer uses the German word “sollen,” which does not mean the same as our word “ought.” When he notes that “sollen” is the imperative form of ethics, he is saying that it expresses commands, not truths. This is why he says it belongs to theological morality – that is, it expresses authoritative commands. Our concept, “ought,” is quite different. When I say “You ought to do X,” I don’t mean “Do X!” I use it in the indicative rather than the imperative. “Do X!” is neither true nor false. But “You ought to do X” can be either true or false. For this reason, the quotation from Schopenhauer is irrelevant to my argument in the piece on predation.

  • Mark Reid

    “I take it Kant thought animals had no moral standing, so from the Kantian moral perspective, there is nothing objectionable about factory farming.”

    This is an example of a careless misuse of Kant’s philosophy. For Kant, few things are farther from the truth. In the Doctrine of Virtue, which he wrote later in life after very many years of thought and discussion, he writes:

    “The human being is authorized to kill animals quickly (without pain) and to put them to work that does not strain them beyond their capacities (such work as he himself must submit to). But agonizing physical experiments for the sake of mere speculation, when the end could also be achieved without these, are to be abhorred” (DV 1.2.17).

    About the factory farming of animals, Kant could have not have fathomed it. Factory farms impose a suffering, however, that lasts not just for the duration of a Cartesian vivisection experiment that Kant has in mind but for the entire duration of their lives, which supports the conclusion that Kant would have abhorred the factory farming of animals. Factory farms confine animals for the entirety of their lives, in their own excrement, often in cages too small to turn around or even lie down. If someone has not visited one, then one really has no idea. The conditions of a factory farm can be merely suggested through a description in words. Animals are routinely electrically prodded, killed in front of each other, and when the dismembering process begins, most are still conscious.

    All “when,” in Kant’s words, “the end could also be achieved without these.” A vegan diet is at worst something that requires an inconvenient lifestyle adjustment, while at best, it is a less violent diet that increases one’s lifespan without contributing to the horrific phenomenon of food factory farming of animals. The end–nourishment and gustatory pleasure–could also be achieved without these, and contra Brian, both Kant and Kant’s moral philosophy abhor the factory farming of animals.

    Even the argument that humans have (merely) indirect duties to animals does not support any of the animal factory farming institution or other atrocities such as cosmetic testing on animals, and perhaps worst of all the Asian fur trade . Kant writes that “Even gratitude for the long service of an old horse or dog (just as if they were members of the household[!]) belongs indirectly to the human being’s duty with regard to these animals” (ibid.). Kant’s views as expressed in the Doctrine of Virtue, which Kant wrote over a much longer time and after he wrote the Metaphysics of Morals, are incompatible with institutionalized mistreatments of animals today.

    To cite Kant as supporting them reflects an ignorance of Kant’s philosophy as well as an ignorance of the actual treatment of animals in them.

    • Brian Leiter

      I’m a bit puzzled that on the basis of one, rather ambiguous passage, Mark Reid deems it obvious that Kant would have deplored factory farming. We know Kant thought there were instrumental reasons for not killing or being cruel to animals. The passage quoted seems to rather clearly imply that it is fine to cause animals agonizing pain if it is the only way to achieve an important (morally important?) end. Since non-human animals are not rational agents, they are not moral agents for Kant. Korsgaard, as Jeff notes, has some quite complicated arguments purporting to show that Kant should have thought otherwise by animals. I think the key point is that on Jeff’s view, if the argument doesn’t work, then Kant’s ethics really can’t be part of “the moral perspective.”

      • Mark Reid

        Something puzzling is how Kant’s “rather ambiguous” passage “clearly implies” something. Moreover, I nowhere state that I think that it is obvious that Kant would abhor factory farming. I conclude from two premises (P1) Kant abhorred mistreating animals, especially when there are alternatives, (P2) a vegan diet is an alternate to the mistreatment of factory farms, that (C) therefore, Kant would abhor factory farming. (Kant also believes animals have sensation and choice). Moreover, the cited passages are not merely random or unimportant comments; they are decisive statements in the Doctrine of Virtue.

        Let me be transparent on why this matters to me. The plight of animals in our world today is a horrifically daunting nightmare. The Asian fur trade and other atrocities can be witnessed on you tube. Billions of animals in the US annually are consumed or subjected to agonizing misery, usually both. Sadly, most people could not care less.

        In moral philosophers, we have a rare hope, perhaps one of the only hopes. To then see that some moral philosophers might think that with Kant’s moral philosophy they have “a way out” of caring about these issues is disheartening. I also happen to believe that it is plain wrong and I have shared why.

      • Brian Leiter

        Mr. Reid, it is very nice that you are concerned about animal suffering, but it does not warrant all your mistaken assumptions about the point of my comments and questions. I am not a Kantian, and I am not trying to make a moral argument in favor of factory farming. I really wanted to understand how Jeff McMahan understood “the moral perspective,” whether it necessarily ruled out Kant’s views, and whether this committed him to some kind of moral realism and, if so, which kind.

        The passage from Kant that you quoted was ambiguous in its first sentence: “The human being is authorized to kill animals quickly (without pain) and to put them to work that does not strain them beyond their capacities (such work as he himself must submit to).” The curiosity about this formulation (I have not seen the German) is that it does not make clear whether there is a duty to only kill animals quickly and without pain, or whether this is a permission, or something else. The second part of the quote, on the other hand, namely, “agonizing physical experiments for the sake of mere speculation, when the end could also be achieved without these, are to be abhorred,” seems to imply clearly that “agnoizing physical experiments” are fine if not for “mere speculation” and if they are the only way to achieve some (important, I assume) end. Since factory farming makes possible for the first time in history the very widespread availability, at relatively low cost, of one kind of source of nutrition for human beings, it is hard to see Kant being exercised about it.

        In any case, you fail to address the central fact about Kantian moral theory, namely, that moral standing depends on rational capacity, which animals (not only animals) lack.

        All of this may, from the utilitarian perspective, simply amount to a reductio (as Jeff says) of Kantian moral theory.

  • closetpuritan

    In response to Tom Rowe’s idea of artificially created meat “vending machines”: that’s actually the only remotely feasible suggestion I’ve seen for how to deal with this problem.

    It ignores the fact that animals will reproduce until resources can no longer support their reproduction, though. Most animals are most strongly limited by food, although, for example some will not breed if there’s not a large enough territory for them. (They might well evolve to need smaller territories if there came to be more food in a given territory, though.) We’d have to increase artificial meat production exponentially as the predator population increased–and I do mean “exponentially” literally, not as hyperbole. At some point either we’d run out of capacity, or the predators would not have enough space and get involved in more and more territorial disputes, leading to the animal death we had been trying to prevent. The fix for this would be easier than trying to elinate predation, though: go and sterilize the predators AND the herbivores so that their population doesn’t increase too much. This would be difficult for humans to do, though.

    I know that McMahan doesn’t WANT to talk about the impossibility of “directing evolution” to eliminate predation without causing starvation among herbivores, but he seems to equate “talking about something I don’t want to talk about” with “missing the point”, which I find condescending. Not only that, but he also defends the possibility of “directing evolution” [“But I also noted that our understanding of ecological science is likely to advance enormously over time.”], and if all he wanted to do was to make a philosophical point, he could say, “Maybe you’re right and it is impossible, but I just want to talk about what we would do if it WERE possible.”

    Other people don’t seem too keen on explaining WHY this is basically impossible, so I’ll wade in. First, in order to prevent herbivores from starving to death, you’d have to reduce their reproduction (which predation currently does by killing some animals before they’ve finished reproducing). But the force of evolution drives living things to maximize reproduction. Say you introduced a mutation so that female deer only had two fawns and then stopped giving birth for the rest of their lives. In relatively short order, evolution would be sure to come up with a mutation that allowed them to keep on reproducing. The does that could have more than two fawns would (obviously) leave behind more offspring than the others, and would soon outnumber them and greatly increase the deer population. It is not much more plausible that you could keep predation out of the animal kingdom. It’s not like, say, a spine, that only one clade of species has evolved–it’s evolved independently countless times. Any species that can find a new food source to exploit can multiply rapidly, because for a while, there is no competition. The only way to keep these things out of nature is to keep finding and killing/sterilizing any animal that evolves a trait you don’t want animals to have. That’ll reduce their reproductive fitness! I suppose that it could be possible with enough technology to monitor the entire animal kingdom and robots to go out and dispatch the undesirable animals, but I don’t think that’s what you had in mind with “directing evolution”.

    The idea that we can eliminate predators without causing herbivore populations to expand to an extent that their primary cause of death is starvation is about as plausible as the idea that we can escape the laws of thermodynamics and prevent entropy if only we learned enough science.

  • Victor Tadros

    For Jeff’s project, the crucial questions with respect to Kant are

    1) on the Kantian view, is there a reason, or perhaps a duty, to prevent the suffering of animals where we can, as well as a reason not to cause them to suffer.

    2) on the Kantian view, is it ever permissible to force others to do so

    Mark’s comment indicates that Kant, at one time at least, believed that causing animals to suffer for insufficient reason is abhorrent. But did he also believe that there is a reason or a duty to prevent the suffering of animals where that suffering is not caused by humans? If not, his view is still abhorrent (A horse is trapped under a fallen tree causing her great pain. I could prevent the pain at no cost to myself, and I am the only person who could do so. I believe I have a duty to rescue the horse. I think it abhorrent to believe otherwise. I also think that others are permitted to force me to do so if I don’t do my duty.).

    2) leads us to a question not addressed by Jeff, but which is important for his project: would it be permissible for the state to prevent the suffering of animals by enforcing a law that makes most carnivorous animals extinct, or almost extinct, (in the right factual circumstances)? I take it that state involvement would be necessary to carry out Jeff’s project.

    Kant, as I understand him (though only second hand) thought that it is wrong to interfere with innate right simply to prevent harm. If so, it is difficult for him to motivate laws preventing cruelty to animals simply in order to prevent animals suffering. This is also, I believe, an abhorrent view that would imply that the prohibition of factory farming is wrong. And it would undermine the feasibility of Jeff’s project even were we to know of the side-effects of making most carnivorous animals almost extinct.

  • Gerardo Camilo

    The great John Maynard Smith formalized the application of game theory in evolutionary biology in the early 80’s. This formalization has been well tested and applied to many cases and situations, resulting in a very robust theory known as Evolutionarily Stable Strategies (ESS). ESS is commonly taught in introductory evolution courses, as well as animal behavior, evolutionary ecology, etc. The formal definition of an ESS is a strategy (set of rules that an animal follows) that can’t be invaded by an alternate strategy. For example, if I am a herbivore, and I follow all the rules of a herbivore, as well as every one else in my population, then, an alternate strategy called carnivory, can’t invade if herbivory is an ESS. But in this view of life there is much more than just herbivores and carnivores. So, let’s consider omnivory and put our ESS hypothesis to a test.

    There are two ways in which omnivory, the consumption of both plant and animals, can evolve. First start from a carnivore, like a bear, and start adding more plant material to your diet. This requires that this bear evolves the required digestive metabolism, as well as the behavioral preferences for, let’s say berries. That’s not too hard because berries are mostly simple carbohydrates and sugars. For omnivory to evolve among these bears, a mutant omnivore bear must have to have more babies than the strict carnivorous ones.

    The second way of evolving omnivory would be to start with a strict herbivore and start adding meat to the diet. That’s a bit trickier because animal tissue is mostly protein, but still doable. Many herbivores have significant protein loads in their diets in the forms of seeds, nuts, and other specialized plant structures. Consider the case in which food resources are scarce. Hunger is a fantastic motivator. A very hungry herbivore runs into a carcass (given that there are no predators in this environment, there are lots of carcasses laying around). This herbivore has a choice, to try or not to try. Some, if not most, herbivores will pass, and thus die due to starvation. But one individual has a bite, enough to allow it to survive long enough until resources are replenished. That individual will pass on it’s gene better, thus invading the herbivore strategy and, with enough time, replacing it.

    Let’s know consider Professor McMahan’s herbivorous utopia where all animals live in perfect harmony. Given that there are no predators in this system makes it ripe for a predatory strategy to invade. This new predator will be completely free of competition as well as from predation, given that there are no other predators in the system. Thus, given enough time, we will be back where we started.

    BTW, morality, just like the odor of a molecule, the beauty of a flower, the gentleness of a summer breeze, etc, resides in the evolved brain.

  • Maria Comninou

    Please excuse me for expressing my non philosophical thoughts in this forum.
    I find all the comments about the meatless apocalypse tired and tiresome!
    As a dietary vegan for compassionate reasons (overwhelming pity), as a person who would be willing to eat a pill or a handful of dirt engineered to stop hunger and sustain life, I find all the philosophical arguments mere gut excuses to continue the status quo for those who are not affected by the status quo. Those that are not eaten.
    Discussing carrots, bacteria, etc, is merely avoiding the issue of dealing with the larger problem of predation in this world. Life on this planet is defective from the start: life feeding on other life. We can at least minimize suffering: eating a carrot causes less suffering than eating a cow. If that cannot be assumed as true, we cannot discuss anything meaningfully.
    If you are moral philosophers and teachers of ethics, I invite you to just do your part today. Remove one conscious animal from your diet without substituting it with another conscious animal and become less of a predator. It will not affect nature or the ecology negatively. There is a lot of ecology out there in the cosmos, and it does not care. It has no moral standing either!

    • Chris Desopoulos

      I don’t think anybody is arguing against vegetarianism, veganism, or any other actions that reduce the effect of humans on the well being of other life. I certainly advocate that… It’s our business and our responsibility to reduce our impact. I for one am thankful that you are acting on your ethics, and certainly consider your actions and thoughts to be philosophical.

      I do have a problem with saying that life on the planet is defective — maybe that’s just me. I see life on this planet is an overarching system that defines everything we know and are, from the meat of your body to the process of your consciousness. To say life itself is defective is like saying rocks are defective, or water, or hydrogen. At some point, don’t you have to take the stuff of your world and say it simply is, as it is? Sure, you can change yourself and strive for perfection there. But how can you perfect the stuff of your world? It would make more sense to just leave… Maybe technology will some day allow that.

      But metabolism is part of the definition of life — here. And metabolism is consumption. And higher orders of life save energy by consuming other life. Just as water flows downhill, evolution takes energy-saving shortcuts. Life, humans, the planet, perhaps the universe, would be very different if this was not so.

  • Chris Desopoulos

    I just can’t discuss this in practical terms of species manipulation — the hubris makes my head hurt, and the complexity we’re pretending to consider is so far beyond our ken as to make discussion meaningless. So…

    What if we stepped back and said, let’s remove predation from human politics. Whenever people violate the rights of others, or do other violence, suffering is the result. Should we not want to remove that suffering? Or must we accept that the beautiful and terrible predators are a necessary part of the world — they have some intrinsic value that we don’t want to live without?

    My argument against the original proposal is that it’s not beneficial to take from the world things that we don’t agree with. Predation is part of the landscape, the background against which we define ourselves. If we make the world look like what we want, then we have lost something. I exaggerated the point to say we would ultimately lose ourselves if we carried the project to its extreme, and controlled every species to make them all match our ethics.

    Human suffering is easier to deal with, because it’s us anyway. And I wonder, can I still argue against doing away with predation in politics, just as I argue against Prof McMahan’s project? What would we lose if we imposed a judicial system so rigorous that nobody’s rights were ever violated?

    In the first place, you could say we lose politics altogether. If no rights are ever violated, or if a system is in place to ensure full restitution in every case, then there’s nothing left to discuss, is there? Politics exist to moderate or maybe modulate the human instinct to take advantage of other people. If nobody ever violates anybody’s rights, then we have utopia, and there’s no need for further development of laws. Everybody has what he needs, and can pursue whatever he wants (as long as he doesn’t violate any rights).

    We do away with adversity. And that raises the question, do we need adversity to motivate us? Many people think so. If I read my Darwin correctly, without adversity species wouldn’t exist, which means we probably wouldn’t be here. But that’s history… The question is, are we wired, by virtue of the adversity in our past, such that without it we don’t improve our lot? In a way that’s a dumb question… Without adversity what does it *mean* to improve our lot? How could it get any better? But really, if we lose adversity, what else have we lost? I ask that in all seriousness.

    We value heroism — would we have any heroes if there was no injustice? I guess heroes would resist natural disasters, but we would still lose the kind of heroism we see in Martin Luther King or Ghandi.

    I’m not sure I can come up with other losses, but I’m sure there are more.

    Let me be clear… I’m not advocating human suffering, nor am I saying social predators are beautiful or even intrinsically valuable. And I definitely think we should work as hard as we can for perfect justice where nobody’s rights are ever violated. But I also think we will never achieve that utopia. Again, the system is just too complex. And in fact, I believe we would not be human if we did achieve it. We might be better than human, or we might be worse — reduced to ants that have no ambition outside of the task at hand.

    Somehow, I think certain things are facts of life. You can try to end suffering, but suffering is still a fact of life. Life is competition for resources, and that ultimately means predation of some sort. I think it’s a good idea to try and get rid of human predators, but I don’t think I’ll ever succeed once and for all. As for all the other species of predators… Well, when I’ve finished with all the human predators I might have time to think about that.

  • Maria Comninou

    Is it lack of imagination or refusal to imagine?
    Life does not have to be in our image. Just as some of the SETI project researchers consider now
    that alien life may not even be biological, I can imagine life not based on the “selfish gene”,
    which may or may not be responsible for predation.
    The ultimate of hubris, as I see it, is to believe that it is hubris to imagine a different world
    from the one we are part of.
    As for utopia, isn’t the current state utopian? How many human predators can the planet sustain?
    If all else fails, our dying sun will put an end to suffering in a few billion years! Just stick around.

    • Gerardo Camilo

      Aldo Leopold, the father of the modern conservation movement, and also a great ecologist, opens the winter section of “A Sand County Almanac” with these words: There are two spiritual dangers in not owning a farm. To think that heat comes from a furnace, and that food comes from a grocery store.

      We are children of the Earth, and thus we are bound by the beauty of the relatedness of life. I agree that there are serious ethical, environmental and public health issues in the industrial meat system. Furthermore, in the US we consume way too much meat. But that is a separate issue. What you may perceive as barbarism, I perceive as the beauty of nature in all it splendor.

  • It seems to me his basic message is that predators cause suffering to their meals and that this is a moral issue for humans that requires attention. But the suffering of all living entities resides in a much larger context than the suffering of predator’s meals. Every form of life suffers during its existence. What he wants to do is consume enormous energy and resources to reduce a subset of universal suffering, with no assurance that the effort will reduce overall suffering because we don’t know the implications of eliminating predators. Do we reduce suffering by eliminating the species consumed by predators? Predation is a Gordian chain of predators consuming predators and I think therefore not a feasible project for human effort.

    His concept that we need to minimize the suffering we cause animals we consume does have merit as long as we want to believe we are just, merciful and humble people. If we want to shrug our shoulders and say it’s the way of the universe, we could ignore it, but that is immoral. Reducing our predation and the suffering of those animals is a more limited scope project that is worthy of our effort. Beyond that ‘tis folly fostered by frivolous musing.

  • Paula Casal

    Could a small modification in the last paragraph illustrate the application of the article´s logic to other cases?

    Giving birth is painful for humans and other mammals. “It would be good to prevent the vast suffering and countless deaths” caused by giving birth. “There is therefore one reason to think that it would be instrumentally good” if no-one gave birth, and the relevant “species were to become extinct and be replaced by new” oviparous “species, provided that this could occur without ecological upheaval involving more harm than would be prevented by the end of” these species. “The claim that existing animal species are sacred or irreplaceable is subverted by the moral irrelevance of the criteria for individuating animal species. I am therefore inclined to embrace the heretical conclusion that we have reason to desire the extinction of all” viviparous “species”.

  • It’s getting better – It’s getting better all the time

    Torbjörn Tännsjö
    (Stockholm University)

    The content of my comment to McMahan is close to a never published talk, presented in a discussion with Peter Singer in Lisbon in 2003, and at several other occasions since then; the idea was to try to assess whether the world had become a better or worse place since 1975. The situation 1975 was compared to the situation 2000. I haven’t been able to update the statistics, but the trends I discuss seem to have been continued. The upshot of the investigation is that the situation in the word has become better, much better, during the last 25 years. In my discussion I take classical hedonistic utilitarianism for granted. My conclusions are both different from, and similar to, McMahan’s.

    According to classical utilitarianism we ought to maximise happiness.

    Let us assume, then, that total hedonistic utilitarianism is correct. There are two ways of making the world better place, either by making existing individuals happier, or by making (additional) happy individuals. What then about the situation of the world today, as compared with 1975?

    Well, simple population statistics informs us that, while some 4 billion people lived 1975, the world now sustains a population of 6 billion people. Let us make the rather pessimistic assumption that people living in poverty (with an income of less than one US dollar a day) lead lives worth not experiencing. We then find that the number of people living such lives is roughly the same today, as compared to 1975 (about a billion people). At least, since the measurement was invented (in1987), the number of people living in poverty has been the same (1.2 billion). This, as such, is a scandal, of course, but in our assessment it means: no difference!

    We also see that the people who live privileged lives, materially like the ones most of us at this conference lead, is also about the same, 1 billion. Again this means, given the assumptions in this paper, no difference!

    It is reasonable to assume that the number of people living lives worth living means compensation for the misery experience by those who don’t. This was true already in 1975, I am prepared to argue, and it is even more true today, when some two billions have entered the picture, living lives better than those lived by the poor people.

    What has happened to the population of other sentient animals?

    If we consider animals kept by people for food and other products, the following picture emerges. I will focus on a few important species:

      1975 2000
    Cattle 1,2 billions 1,3 billions
    Chickens 5,9 billions 14,7 billions
    Goats 0,4 billions 0,7 billions
    Horses 0,06 billions 0,06 billions
    Pigs 0,7 billions 0,9 billions
    Sheep 1,0 billions 1,1 billions

    There has been an increase of the population from 8 billions to 17 billions. The probable explanation of this fact is that there is a causal connection. We hold more animals because we eat them, and because we who eat them become more numerous. The number of dogs, cats, and rabbits, and so forth, held as pets, moreover, is constantly growing.

    What about the number and fate of mammals and birds in wild life? Here it is impossible to find relevant statistics. How many are they, in the first place? I have questioned all sorts of expertise. Most experts are reluctant to make even a rough estimate. One has been willing to do so, however. His conjecture, built on speculations about the average number of members of various different species, is that there are 100 billion birds (most of them small or middle-sized), and 50 billion mammals (where rodents, bats, and insectivores dominate the picture completely). According the same assessment, there is really no reason to believe that the population of birds and animals has decreased during the relevant period (1975-2000).

    If the rough picture here drawn is correct, if the number of sentient animals living wild life has at least not decreased, and if the number of sentient animals kept in captivity (for food, other products, or as pets) has increased, does this mean improvement or decline? My strong intuition is that it means improvement.

    Here two assumptions are essential to my argument.

    First of all, animals living in captivity are for most of the time (on the whole) living lives worth experiencing.

    Secondly, animals living wild life are, even if they may well lead worse lives than animals held in captivity, living lives that are, most of the time, worth experiencing.

    This is not to deny that, certainly, animals held in captivity often experience a terrible time awaiting their being butchered (being transported, kept in narrow slaughterhouses, being actually killed in a less than painful manner). And this is even truer of animals living wild lives (often suffering from famines, actually starving to death, or being hunted down and eaten alive slowly by predators). This is explicit concern in McMahan’s paper. However, my conjecture is that both animals held in captivity and animals living wild experience on average enough happiness to compensate for these terrors.

    Even if the negative aspects of happiness should not be neglected, the positive ones are, in the long run, more important. So if we want to continue with a kind of moral progress, beyond the point where we have solved the problems of world poverty and animal misery, we should see to it that the number of sentient beings is constantly increasing. How should this be accomplished?

    In the future, an important task for humanity will be to colonise space. This means that an almost indefinite increase of the sum-total of happiness, for an indefinite period of time, can take place. This notion of putting our eggs in more than one basket means also some reassurance against natural or self-inflicted disasters, threatening to put an end to sentient life in our region of universe. Many Noah’s arks, containing both human beings and other sentient animals, carefully selected with respect to their chances of leading good and secure lives together, should be sent out in the near space.

    Ought we to become vegetarians? If my argument is correct, we should do nothing of the sort.
    It is sometimes claimed that, if we become vegetarians, then the world can sustain an even larger human population. This is probably true, but from the point of view of total hedonistic utilitarianism, irrelevant. Other species, capable of experiencing happiness, are no less important than human beings. And by keeping animals in captivity, providing them with good living and dying conditions, exchanging one generation for another, we can see to it that much happy life is constantly kept going.

    Here one of the most urgent tasks emerges, with respect to the situation in the world. The living and dying conditions of animals held in captivity are in many respects terrible, and they could rather easily be improved. If the animals raised for food experience good living and dying conditions, then they do indeed lead lives worth experiencing, and they have our interest in raising and eating them to thank for their lives.

    Finally, when we consider wild life, we must be prepared to think in terms of extinction of entire species. Here I am in complete agreement with McMahan. Those animals, living poor wild lives, having to predate on others, or being constantly subjected to attacks from predators, famines, and the like, should probably not exist at all. They certainly will not be among the species allowed to occupy a place on Noah’s space-ark.

  • ingmar persson

    It seems incontestable that the natural world would be a morally better place if the suffering that carnivorous animals cause was less, other things being equal (that is, if the suffering caused by other factors, such as painful diseases, starvation, natural catastrophes, etc. was not greater). So, if evolution right from the inception of animal life could have taken the course of producing a natural world containing only herbivorous animals, but in other morally relevant ways similar to the actual world, it would be morally desirable that it had done so.

    It does not follow, however, that it is morally desirable to change the actual natural world, with its carnivorous inhabitants, into such an alternative world. As McMahan points out, this could have bad effects – the suffering of carnivorous animals, the ecological upheaval that their disappearance would have in its wake, etc. – that are worse than the suffering eliminated. If we tried to effect such a change now, or in the imminent future, this is more likely than not to happen. For, as McMahan is well aware, our knowledge of ecology is crude, and so are our means of disposing of carnivorous animals. But suppose that our ecological knowledge and means of ‘cleansing’ nature of carnivores grew to the extent that we could prevent the suffering they cause in a manner that diminishes suffering overall. Ought we to do it?

    I think not, since it is likely that in the future we shall discover much better means of preventing the suffering caused by carnivores which we cannot use because we earlier used cruder methods (e.g. if we have exterminated carnivores we cannot turn them into herbivores by some subtle genetic engineering). It seems that we will forever remain in this position. One might here be reminded of Karl Popper’s rejection of social utopias and large-scale social engineering in favour of ‘piecemeal’ social engineering in The Open Society and Its Enemies. Nature, as we know it, is a moral inferno, and so is human society, as we know it. These sorry states could make one wish for the removal ‘at one fell swoop’ of all the suffering and injustice they contain. This is indeed what an omnipotent and omniscient being should try to bring about, a world which is at least as good as any other possible world. But we better never try it; if there is any defensible meaning in the injunction that we should not play God, it is that we should not act as though we were omnipotent and omniscient. It is likely that it will forever be best for us to stick to a piecemeal approach – which as regards animals is what McMahan calls ‘our primary duty … to stop tormenting and killing them’.

  • Mark Reid

    I disagree with just about every comment I have read here and on The Stone. The world would be a much better place if more animals populated the earth who eat vegetation, and we ought morally to strive for it.

    We ought morally to enact McMahan’s proposal now.


    1. Predation is not a necessary genetic selector.

    2. The world could exist with vegetation-to-animal-species lifecycles, e.g., plants being eaten by elephants, which then fertilize the soil, which then grows more vegetation.

    If these two premises are true, then it follows that Jeff’s thesis is valid now, i.e., not merely premised on a thought experiment.

    In this comment, I claim that much less predation and carnivory in the animal world would be better even now (i.e., no thought experiment needed). I claim that McMahan’s thesis is a normative argument that applies, not merely in a thought experiment, but in the world as it is now.

    It is obvious to anyone who has considered the matter that many large bodied species are strictly herbivorous (or omnivores with a very low level of carnivory), e.g., gorillas, elephants, rhinoceros, giraffe, camels, Perissodactyla, Mysticete whales, the largest bats. I claim that the world would be better if there were more.

    On Premise 1.
    Many claim that predation is necessary for genetic selection. Predation is certainly necessary for genetic selection against the genes that result in being preyed on. Predation is the reason that gazelles run fast, but it is not necessary for survival in the absence of predators. The main selective pressures are born out in utero. Miscarriage occurs when an organism is not compatible with life. Anyone who has worked in a neonatal intensive care unit knows that “it’s a jungle in there,” so to speak.

    If the claims about the supposed necessity of predation were actually true, then our species would have already died out sometime after the controlled defense against predators tens of thousands of years ago and before the rise of modern medicine (modern medicine is a different story). But the fact is, we did not die out and predation is not necessary for survival. There is extensive background selective pressure just in the fact of being compatible or incompatible with life. Moreover, there are additional selective pressures just from how tough it is to survive in the wilderness without the added pressure of predators. (If you have lived in the wilderness, you will appreciate the power of nature to select, even in the absence of predators. Predation is only necessary to grow a population that is faster (gazelles) or larger (elephants and baleen whales), or more agile (monkeys), or slower (sloth), or smarter (delphinid cetaceans or primates generally). But, you do not need to be faster, larger, more agile, slower, or smarter in order to survive simpliciter, that is, in order to be able to eat, grow, find protection, reproduce, invest in offspring, etc. To think you do is to be mistaken. The idea that predation is a necessary natural selector is a myth.

    On premise 2.
    There is no need for predation. It is perfectly possible to have only gorillas, elephants, deer, horses, vegan humans, and so on. People in The Stone and on this comment thread claim that this would be disastrous. But, I doubt it would be disastrous, and no substantive supportive claims have been made demonstrating that this would be a bad thing or evolutionarily unstable. What harm could there possibly be in it being such that organisms die natural deaths with their bodies decaying into fertilizer rather than having them be consumed (while still conscious) by predators, which then die and decay into fertilizer? And, it strikes me as likely to be better to die a natural death naturally than die an early death in the grip of a predator.

    Jeff’s thesis is thus valid now, not merely as a thought experiment.

    • Chris Desopoulos

      It might be true that predation is not necessary, per se. Unfortunately, there’s no way to demonstrate that on this planet. But the fact is, predation arose. Why? Because evolution, if anything, is a hunt for shortcuts. And the more refined the proteins an organism can consume, the shorter the route from consumption, through metabolism, to the final products that yield repair and reproduction. It’s precisely these kinds of shortcuts that allow for higher and higher orders (if you can excuse the qualitative connotations of height), ultimately yielding complexity sufficient for consciousness and, beyond that, symbolic thinking and introspection. So if you want to accept evolution as an explanation of where we come from, then you have to admit that if predation isn’t strictly necessary, it is at least highly probable. And also that our species arose out of a web that includes predation.

      If you want to take on Jeff’s project, then you have a binary choice ahead of you. Either believe that we’ve reached the end of evolution, or believe that you can sustain the long-range effects of your tinkering. The first choice I find hard to accept. The second means that resurgence of predation is probable, and you’ll have lots more work ahead of you.

      In that vein, I refer you to Monsanto and Roundup Ready crops. The idea was simple… Genetically engineer crops that can absorb Roundup, a relatively benign herbicide, so that we can make more toxic herbicides obsolete. This seems ethically similar to Jeff’s project, as it would reduce the suffering associated with highly toxic herbicides. A mere 10 years later these crops are invaded by a super-variety of pigweed that can absorb Roundup. Monsanto now subsidizes the use of the stronger, more toxic herbicides — in other words, the project has ensured the continued use of these poisons. I see no reason to expect this principle to not repeat itself. Wipe out all the predators, and you can expect some super-species of predator that’s even harder to control. And so on.

  • Bob Farmer

    There is a basic question here that is mostly ignored: What gives us (homo sapiens) the right to decide morality for an entire eco-system? We assume that we have the right to determine the existence of another species because their very existence offends our sensibilities. Based upon this logic we are no better than the animals we suggest eliminating. Let’s start with the most dangerous and invasive species first……

  • Cheers to Jeff McMahan for stating, in eloquent and well-argued terms, what should be obvious. Unfortunately, it seems to be far from obvious, even among antispeciesist (“animal rights”) activists and thinkers. That fact has always appeared strange to me. I think the issue is a key one, an indicator of how serious we are in our desire to take non-human animals seriously. We can’t hold that the suffering of an animal is bad when it is at the hands of human predators, but that it doesn’t matter when it is caused by another nonhuman animal.

    A reference that should be noted: Steve Sapontzis, Morals, Reason, and Animals, 1987, chapter 13, “Saving the Rabbit from the Fox”. A French translation can be found online on the website of the Cahiers antispécistes. In France, several antispeciesist activists took up the predation question back in 1996, and the entire issue #14 of the Cahiers antispécistes is dedicated to the problem.

    Concerning the “we have no right to meddle with nature” argument. As noted by Stephen Webb, our control of the “natural” world is increasing. It’s like having a baby thrust into your hands; you didn’t choose it, but you have it. We are the stewards of the planet, whether we like it or not; our responsibility is to be benevolent stewards. One quote I like a lot:

    Frodo: I wish the Ring had never come to me. I wish none of this had happened.

    Gandalf: So do all who live to see such times, but that is not for them to decide. All we have to decide is what to do with the time that is given to us.

    Another important reference, in my mind, is Daniel Botkin, Discordant Harmonies. It shows how so many of our conceptions about nature being “balanced” are simply false. The picture we have, for instance, of a kind of harmonious relation between prey and predators, the latter being necessary for the stability of the population of the former, are very much overdone. It may be true in some cases, but there is no reason to believe it always is, or even that it often is. The simple fact that the predators themselves, such as wolves or tigers, have no predators of their own (nor do elephants, etc.), without having a “population explosion” problem, shows that there is no general law in the matter.

    “Predation” is a catch-all term that covers many many different situations. It’s like the word “disease”. Some diseases are much worse than others, and some are much easier to cure than others. Recognizing that predation is an evil does not imply that we must be able to cure all predation. There is no reason for it to be all or nothing matter. It is nonetheless important to recognize that it is an evil. I don’t know the cure for AIDS any more than Fred Phelps does, but the fact that I see AIDS as an evil, and that he sees it as a blessing and is impervious to the suffering of the victims, does make a lot of difference between us, and makes a lot of difference concerning what we will do or not do to alleviate, and perhaps some day remedy, the problem.

    Like Mark Reid, I believe that the issue of predation is not just for the far-off future. We cannot abolish all predation now, but there are many choices of ours that can be affected if we keep in mind the suffering of prey animals.

    I do think, however, that the issue implies hard thinking about many questions. Not only factual questions, but also philosphical ones. Is death necessarily a great harm? I actually don’t think so, and I think that the forms of predation that cause great suffering are more urgent to address than those that “only” cause death. That is, of course, debatable. Also, the fact must be kept in mind that predation may oblige many animals to live in a permanent state of terror.

    Furthermore, as I said, the issue is a key one. The animal movement can be seen as a reactionary attempt to “return to nature’s laws”, or as a progressive one, an attempt to better the world by casting away the age-old predatory logic. Our attitude towards the oldest and most cruel of “natural laws” will decide what way the movement goes.

  • David Benatar

    Jeff McMahan begins his excellent essay with the important insight that at every moment there are millions of predators “stalking, chasing, capturing, killing and devouring their prey” and thus that “suffering and violent death are ubiquitous and continuous” in nature. The conclusion of his essay is that “we have reason to desire the extinction of all carnivorous species” – a conclusion that he recognizes is heretical to many ears.

    In my view his conclusion is not heretical enough. We have reason to desire the extinction not just of predators, but of all conscious animals. (This includes both predatory and non-predatory humans.) While it is true that predators cause unspeakable suffering to those they hunt, it is sadly true that suffering is so deeply entrenched in the structure of conscious life that the extinction of predators would not eliminate or even significantly reduce it.

    Professor McMahan shows some recognition of this when he considers the Malthusian catastrophe that would result if herbivorous populations were left unchecked by predators. However the problem extends well beyond that. Even if herbivores’ population growth could be controlled in some painless way – such as contraceptives in the water sources – massive quantities of suffering would still persist. Injury and disease would continue. Some of this would be in younger animals, but more often it would be in ageing animals, which would be a more common phenomenon in the absence of predators. Billions of animals would experience years of suffering as well as painful and protracted deaths. And unlike some (that is, the more privileged) humans, who can seek relief from medical science, almost all wild animals have no such refuge. Their broken bones are not set, and their pain and suffering are not treated.

    These horrors, like those of predation, are hidden from those who take a panoramic view rather than a focused one. Yet they are no less real or terrible, and it would certainly be better if it never existed. While we can imagine some utopia in which conscious beings exist without suffering, pinning our hopes on the realization of such a world is a bet that is guaranteed to lose. Extinction, by contrast, is very likely. It may take a long time, but it will come. There is good reason to think that its arrival will not be a bad thing.

    That we have a reason to desire the extinction of all sentient life does not mean that we should take up the sword. There are many good reasons, that I shall not enumerate here, not to engage in “speciescide”.

  • McMahan’s ideas have real world application in the debate over whether to restore predatory species. Environmentalist policies that favor restoring wolves to places from which they have been eradicated or increasing the number of individuals in an endangered predatory species (such as Florida Panthers) are threatened by his arguments.

    McMahan’s ideas could also be practically implemented by using birth control on both predators and their prey.

    Many find predators to be magnificent animals; might their killing ways be an important part of this value, something we would lose by replacing them with non-violent, look alikes.

  • Paula Casal

    1. There are many sources of suffering (intra-species competition, disease, disability, hunger, old age…). Why single out carnivore’s extinction? If we had divine powers, we could make predation less painful by introducing sedatives into the predator’s saliva and endorphins into its prey’s bloodstream, and do many other things, like lower testosterone to reduce intra-species killing, infanticide, rape, abuse, and violence (which also takes place amongst herbivores).
    2. Extinction is bad. By contrast, being carnivorous isn’t bad in itself. The prey may be dead or saved from a worse death or a life of little, if any, positive value. For carnivores, as the essay notes, reduce net pain: they are nature’s unintentional mercy killers, preventing slow, painful deaths “in greater numbers, from starvation and disease”. And even if there’s reason to wish euthanizers redundant perhaps there is much less reason to wish for their extinction.
    3. We are already decimating the carnivores we’ve not turned into our servants (whales, chimps, bears, wolves, tigers, eagles…) – a tragedy for which the essay gives no solace. Wilderness is everywhere being replaced with artificial groupings of a few humanly controlled species– a sad end to millions of years of evolved diversity and a major cause of climate change.
    4. Carnivores are amazing. Unlike herbivores that just need to chew what’s in front of them, carnivores require intelligence, strategy, memory, and capacities for planning, cooperation, and sharing. They tend to have long, interesting lives and relationships, with many of the attributes that make human lives valuable. On the other hand, carnivores are innocent; their lack of moral understanding and options greatly reduces the moral undesirability of their actions.
    5. Carnivores are irreplaceable. The growth of new weeds does not make up for the loss of ancient baobabs and new species of sheep cannot replace marine mammals. They have different properties and history. New, mutant Dollys may even have disvalue.
    6. The value of conservation is not challenged by the problem of species individuation within ring species. First, the problem is very limited. It is confined to some definitions of species and to very few non-carnivorous species (basically gulls, salamanders and warblers). Scientists are certainly more likely to smooth this out in the near future than they are to invent nature without predation.
    More importantly, we do not apply to other values the reasoning employed here to challenge the value of conservation. Islands are difficult to individuate. Some are joined to each other or become peninsulas with low tide. This does not mean islands lack value. Friendships are also difficult to individuate. They are not transitive, and many times, we cannot even distinguish them from cognate relationships. None of this makes friendship less valuable. Similarly, aesthetic taxonomical difficulties do not undermine the value of art.
    7. The fact that existing species have replaced others in the distant past, does not mean that they can now be replaced with more sheep. The fact that great paintings are often painted on previous paintings, gives us no reason to paint over them.

  • Oscar Horta

    There is one point I’d like to make here in relation to one of Torbjörn Tännsjö’s claims and supporting something Maria Comninou said. It may also be one David Benatar will like, though it’s not based on the assumptions he makes.

    For the overwhelming majority of animal species, the reproductive strategies which maximize inclusive fitness very commonly entail that many more animals are born than those who survive (this is so because they follow what is called an “r-selection” strategy for reproduction). The reason for this is, of course, that the chances that an animal who has just come into existence has of reaching sexual maturity and procreating can be extremely low. This happens in particular in the case of invertebrates, who may lay hundreds, if not several thousands eggs, but also in the case of reptiles, amphibians, fish and other vertebrates. It also happens that these animals are, by far, the ones that exist in the highest numbers in nature.

    This means that the majority of the sentient animals that come to existence die very soon after they start to be sentient. Many of them die from starvation. Others are eaten alive by predators or parasites. This means that most of these animals in almost all certainty experience more suffering than positive wellbeing in their lives. In other words, we have very strong reasons to claim that their lives are not worth living. It would be better for the overwhelming majority of the animals that come to existence not to have existed.

    As I mentioned in a previous comment, this point is explained in Yew-Kwang Ng’s “Towards welfare biology: Evolutionary economics of animal consciousness and suffering”, Biology and Philosophy 10, 255–285.

    So, if we consider the good of individuals, the conclusion is striking, but also very clear: disvalue in nature tremendously outweighs the value in it. This follows if we assume an egalitarian, a sufficientarian, a utilitarian, or a maximin conception of the good, among others. Or if we assume any other view according to which an outcome in which some individuals gets some benefits but some others get harmed cannot be good (as some who hold deontological or virtue ethics approaches may assume).

    Now, this may conclusion may be opposed if we think that there are other values in nature of a completely different sort. For instance, if we think that the mere existence of different species is good in itself (Ingmar Persson’s view seems to be this). However, even conceding that such value does exist –something I, for one, would not do–, would be so high to outweigh the huge disvalue I’ve just pointed at? That doesn’t seem plausible to me, and one argument I’d use to support this claim is that we would never accept it, I think, if those suffering the disvalue were humans.

  • Pat Duffy

    As a biologist I find these comments interesting if a bit simplistic.

    Animals – this is a very general term, most commentators are using the term to mean vertebrates, and especially mammals. Should you not be more concerned with your terminology? I am seeing very little mention of the vast majority of animals, the invertebrates and especially insects (except for the ants, which was a great comment). I am very fond of most insect predators, since otherwise we would have much larger populations of herbivorous insects, including those who eat our crops and fruits and stored products, and those who transmit plant diseases.

    As well, the fact that most of us die (excluding some clone lineages that seem to be almost immortal) means that the issues are how we die and what we do with our lives. Ile Royale was an interesting situation. Before the moose crossed over Lake Superior the island managed just fine with trees and small animals. Moose caused huge devastation as their populations increased without predators, and then they experienced a massive starvation one winter because they had eaten all the accessible food. Is mass starvation over a long period of time a desirable death? And consider the scavengers. There was very little nourishment for them in the moose carcasses. It took years for the vegetation to recover and the moose populations to also recover. Since wolves arrived the moose and wolf populations have been fairly stable (all populations fluctuate) and the vegetation has not been seriously overgrazed. This is true i many situations, predators are a stabilizing influence on herbivore and omnivore populations.

    Another situation – in North America we have acted as God re forest fires, to the detriment of the forests. When we let the Yellowstone fire burn, instead of allowing mass destruction we found that the habitat went back to what it originally had been (a mix of forest and open areas) and the elk population, which had been unhealthy and in decline, was invigorated as fresh browse became available.

    The point of this is that human value systems should not be applied to systems that are the result of complex interactions that we do not fully understand. We have many examples of situations where our interference has resulted in unintended consequences.

    I understand the joy of thought experiments, but they should not be considered to have much relevance to the living world around us, which is a system that we do belong to, even though many pretend we are no longer a part of it.

    And as an aside, our digestive system is omnivorous. Historically human populations have tended to be more vegetarian or carnivorous depending on what was available (think Inuit for a people that historically had little choice). Bears, which are also omnivores, have also done this, polar bears are the most carnivorous and pandas are the most vegetarian.

  • Mark Reid

    If a conscious life has an intrinsic value, and has that value in degrees because of the complexity, range, and depth of its thoughts, emotions, and experiences, then a conscious life has a source of value that challenges the Schopenhauerian pessimism that shadows many of the above comments. I want to try to help us avoid such pessimism. I have battled such pessimism, and I believe that we have good reason to avoid it.

    One issue concerns hedonic states and another concerns intrinsic. Many believe that humans and nonhumans are fundamentally different in their distribution of hedonic experiences. Some believe that humans house a hedonic range that dips low into pain and misery and that soars high into pleasure and happiness, while nonhumans have capacities for suffering that are nearly as deep as humans but not the capacities for pleasure and happiness that humans have. Some believe the reverse of this, and some believe that humans and nonhumans are similar in their hedonic range.

    Set against hedonics, the issue of intrinsic value evokes the question of whether and under what conditions humans and nonhumans have lives that are worth living? Both issues effect how this question is answered. For instance, a conscious life’s intrinsic value can, it would seem, be trumped by hedonic states at least under certain conditions. If someone believes that nonhumans are largely capable of suffering, then the intrinsic value of the conscious life would have to be large in order for that life to be worth living. If someone believes that deep, complex conscious human and nonhuman life has huge intrinsic value and that humans and nonhumans have capacities for hedonic states that are similar and roughly equally capable of positive and negative states, then one would believe that the Schopenhauerian gloom is silly and instead that there is no need to move from the premise that Jeff’s thesis (in some form) is valid to the nihilism of all conscious life. Jeff’s thesis brings the aim, it seems to me, to improve the lot of experiences for conscious life, not remove the whole lot of conscious life.

  • Jeff McMahan

    Again I gratefully acknowledge the courteous, serious, and intelligent character of the comments on my article.

    The article was intended primarily to stimulate careful reflection about potential conflicts among values that most of us recognize and endorse, such as the reduction of suffering and the preservation of species. My claim was that if we faced a choice between the elimination of predatory species (though perhaps I ought to have focused, less provocatively, on the reduction of predation though reductions in the number of predators and perhaps certain selective extinctions) and a great reduction in the suffering of animals, the importance of reducing suffering ought to trump the value of preserving species. But my argument was explicitly conditional: the claim that the reduction of suffering has priority over the preservation of species has practical significance only if the reduction or eliminate of predation could be brought about without causing harm as a side effect that, together with loss of impersonal value through the extinction of species, would outweigh the good of reducing suffering. (For more on this, see the response I posted to comments on my article in the New York Times website, The Stone.)

    “Closet Puritan” and Gerardo Camilo are skeptical that my argument could ever be of practical significance. Mark Reid and David Olivier, by contrast, suggest that my argument has immediate practical significance and that it would be desirable to begin to eliminate predators right away. I don’t have the empirical knowledge necessary to judge which of them is right. But I don’t think the points made by “Closet Puritan” and Camilo are decisive. “Closet Puritan” suggests that if we tried to prevent mass starvation among herbivores whose numbers were no longer controlled by predators, we would have to control their reproduction, perhaps by germ-line genetic manipulation. But our efforts would soon be thwarted by mutations that would give a reproductive advantage to animals that would have escaped the limits we had imposed. Camilo explains the notion of an evolutionarily stable strategy and argues that a region without predators would be “ripe for a predatory strategy to invade.” But it seems that if we had the ability to eliminate predators without disaster in the first place, we would also have the ability to maintain a stable environment without predation. This might involve further genetic intervention to prevent the proliferation of animals with a newly evolved capacity for higher fertility, or efforts to prevent the introduction or evolution of new predators in the region, or interventions to increase the food supply (as we always ought to do to prevent human famine) for an expanded population of herbivores. Evolutionarily stable strategies are relative to environments; thus, to the extent that we can control an environment, we can determine what strategies will be evolutionarily stable and which will not. Perhaps this is all fanciful, but I see no a priori reason to suppose that it must be. And I agree with Maria Comninou that it would be a terrible mistake to suppose that it’s somehow presumptuous to use our intelligence and our moral capacities to try to make our world better. If it could be better but we don’t act to make it so, no one else will do it for us.

    Camilo makes two further points. He asserts, as if it were a truism, that morality “resides in the evolved brain.” Some of the greatest philosophers in history have devoted years of thought to trying to determine whether something of this sort is true. Many have concluded that it’s not. Here are a couple of questions for those who think it is. Do numbers reside only in the brain? If so, does that mean that before brains evolved, it was never true that there were two things in any region of space?

    Camilo also observes that “what you may perceive as barbarism, I perceive as the beauty of nature in all its splendor.” First, animals can’t be barbaric, any more than they can be civilized. Second, even though I don’t think morality is just something produced by our brains, I do think that some instances of beauty are perspectival. A person may derive some aesthetic gratification from the spectacle of a lion stalking and killing a zebra. But we should ask ourselves why one wouldn’t have the same reaction to the spectacle of a lion stalking and killing a human child. Mightn’t the fact that the latter event would not be beautiful suggest that the alleged beauty of the former is an illusion?

    Pat Duffy reveals what I think is a similarly insufficient sensitivity to the suffering of animals. After recounting with approval an instance in which a forest fire in Yellowstone was allowed to burn, leading to a renewal of certain types of vegetation and a consequent reinvigoration of the elk population, Duffy observes that “human value systems should not be applied to systems that are the result of complex interactions…” But doesn’t the judgment that it was good to allow the forest to burn derive from a human value system? It’s certainly an evaluative judgment, one that I suspect derives from a mistaken value system, which sees the growth of “fresh browse” that enables more elk to exist as an important good, but apparently attributes no significance to the fact that forest fires cause many thousands of animals to be burned to death. If there had been human beings in the forest, even only a tiny fraction of the number of animals that were there, no one would have objected to the application of a human value system to the situation and no human value system would have judged it permissible to allow those people to burn to death so that some fresh browse would become available to the elk.

    Chris Desopoulos revives a form of argument found in traditional theodicy: namely, the idea that the existence of certain evils is justified by their being necessary for certain forms of good. Suffering, for example, is necessary for the exercise of the virtue of compassion; if, therefore, it’s important for there to be compassion, there has to be some suffering. I think it would be a mistake to dismiss this form of argument altogether. Shelly Kagan, a philosopher at Yale, has written a paper – still unpublished to the best of my knowledge – that considers what dimensions of human well-being might remain in a utopia from which all evils, or all bad things, had been eliminated. Such a utopia might well strike us as rather tame, shallow, and insipid. But even if it’s true that we require a certain degree of adversity for our well-being, it doesn’t follow that other, simpler animals do. And even if the elimination of all sources of suffering would result in an impoverished world, it doesn’t follow that the elimination of any particular source of suffering would be bad. We would have to eliminate most sources of suffering before any threat of impoverishment would arise. The point here is rather similar to one often made in discussions of the badness of death. Some claim that if we were immortal, life would cease to be worth living, as it would become endlessly repetitive. But even if that were true, it wouldn’t count against increases in longevity that would stop short of the point at which life would become intolerably boring.

    The views articulated by Torbjörn Tännsjö, David Benatar, and Oscar Horta present striking and interesting contrasts. David believes that the presence of any degree of suffering within a life makes it the case that it would have been better had the life never begun. Torbjörn seems to think that even factory farmed animals in general have lives worth living and that it’s better that more of them exist than fewer. Oscar occupies a middle position according to which most factory farmed animals and most animals in the wild have lives in which the intrinsically bad elements outweigh the intrinsically good. All three of these positions are at odds with common sense views. My own view is closest to Oscar’s but the relevant issues are largely though not entirely empirical (a lot also depends on the proper analysis of well-being) and I simply don’t have the expertise necessary to advance a view with any confidence. I will say, however, that I’m unpersuaded by Torbjörn’s reason for rejecting vegetarianism. His argument presupposes principles that are wholly impersonal in character. It presupposes, in particular, that the death of an existing individual is no worse than the failure of a new individual of the same kind to come into existence – indeed that a death is normally less bad than a failure to come into existence since the latter normally involves a greater loss of impersonal value. I find this impossible to believe. (There is some further discussion of this and certain related issues in an article I published a few years ago in Daedalus.)

    I think that Ingmar Persson’s position is correct up to a point. He’s certainly right to advise caution in taking major steps, such as driving a species to extinction, that would be irreversible. Even if it’s true, for example, that the reduction over time in the number of Siberian tigers to just a few hundred has significantly reduced the amount of suffering by other types of animal in the large areas that were once its habitat, it might still be important both for instrumental reasons and because it’s intrinsically valuable that there be Siberian tigers in the world to preserve some members of the species for the indefinite future. The same might true even of dreadfully dangerous microbes such as HIV, which might someday prove to be of instrumental value. But Ingmar’s cautionary principles don’t, as he acknowledges, support a wholesale prohibition of intervention in the natural world. Rather, he recommends a piecemeal approach as opposed to large scale intervention. But what counts as piecemeal will vary with our capacities. What would count as dangerous large-scale intervention now might count as gradualist and piecemeal in a future in which our knowledge had greatly expanded and our methods of intervention had been enhanced.

    Paula Casal, in her two comments, makes various interesting and important points. I don’t have many quarrels with what she says. I suspect, however, that she attributes greater intrinsic significance to the preservation of individual species than I do. When she says that “extinction is bad” and contrasts that with predation not being bad “in itself,” I think she has in mind the impersonal badness of the extinction of a species rather than the instrumental badness. And impersonal badness isn’t bad for any individual. I do accept that there are impersonal values and I think that Lori Gruen is right that the continued existence of a group of animals of a certain sort can be an instance of something with impersonal value, even if the criteria for distinguishing the group from others are lacking in moral significance. But I do question how much weight such an impersonal value can have when it conflicts with the reduction of suffering.

    I have nothing to add to the interesting discussions of Kant. I’m glad to know of the passage Mark Reid cites, though I agree with Brian Leiter that it leaves it open for Kant to approve of “agonizing physical experiments” on animals if they were for an end other than mere speculation and the end couldn’t be achieved in any other way. I also agree with Victor Tadros’s judgments about the views he describes as abhorrent. If Kantian theory were to entail those views, that would be sufficient for me to rule out Kantianism as a viable moral theory.

    Thanks again to everyone for joining in this discussion.

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