This Is Your Brain on Metaphors

Despite rumors to the contrary, there’s many ways in which the human brain isn’t all that fancy. Let’s compare it to the nervous system of a fruit fly. Both are made up of cells — of course — with neurons playing particularly important roles. Now one might expect that a neuron from a human will differ dramatically from one from a fly. Maybe the human’s will have especially ornate ways of communicating with other neurons, making use of unique “neurotransmitter” messengers. Maybe compared to the lowly fly neuron, human neurons are bigger, more complex, in some way can run faster and jump higher.

But no. Look at neurons from the two species under a microscope and they look the same. They have the same electrical properties, many of the same neurotransmitters, the same protein channels that allow ions to flow in and out, as well as a remarkably high number of genes in common. Neurons are the same basic building blocks in both species.

So where’s the difference? It’s numbers — humans have roughly a million neurons for each one in a fly. And out of a human’s 100 billion neurons emerge some pretty remarkable things. With enough quantity, you generate quality.

Neuroscientists understand the structural bases of some of these qualities. Take language, that uniquely human behaior. Underlining it are structures unique to the human brain — regions like “Broca’s area,” which specializes in language production. Then there’s the brain’s “extrapyramidal system,” which is involved in fine motor control. The complexity of the human version allows us to do something that say, a polar bear, could never accomplish — sufficiently independent movement of digits to play a trill on the piano. Particularly striking is the human frontal cortex. While occurring in all mammals, the human version is, proportionately, bigger and denser in its wiring. And what is the frontal cortex good for? Emotional regulation, gratification postponement, executive decision-making, long-term planning. We study hard in high school to get admitted to a top college to get into grad school to get a good job to get into the nursing home of our choice. Gophers don’t do that.

There’s another domain of unique human skills, and neuroscientists are learning a bit about how the brain pulls it off.

Consider the following from J. Ruth Gendler’s wonderful The Book of Qualities, a collection of “character sketches” of different qualities, emotions and attributes:

“Anxiety is secretive. He does not trust anyone, not even his friends, Worry, Terror, Doubt and Panic…. He likes to visit me late at night when I am alone and exhausted. I have never slept with him, but he kissed me on the forehead once, and I had a headache for two years….”


“Compassion speaks with a slight accent. She was a vulnerable child, miserable in school, cold, shy…. In ninth grade she was befriended by Courage. Courage lent Compassion bright sweaters, explained the slang, showed her how to play volleyball.”

What is Gendler going on about? We know, and feel pleasure triggered by her unlikely juxtapositions. Despair has stopped listening to music. Anger sharpens kitchen knives at the local supermarket. Beauty wears a gold shawl and sells seven kinds of honey at the flea market. And Longing studies archeology.

Symbols, metaphors, analogies, parables, synecdoche, figures of speech. And we understand them. We understand that a captain wants more than just hands when he orders all of them on deck. We understand that Kafka’s Metamorphosis isn’t really about a cockroach. If we are of a certain theological ilk, we see bread and wine intertwined with body and blood. We grasp that the right piece of cloth can represent a nation and its values, and that setting fire to such a flag is a highly charged act. We can learn that a certain combination of sounds put together by Tchaikovsky represents Napoleon getting his ass kicked just outside Moscow. And that the name “Napoleon,” in this case, represents thousands and thousands of soldiers dying cold and hungry, far from home.

And we even understand that June isn’t literally busting out all over. And doing this is hard enough as to cause a brainstorm.

Where did this expertise with symbolism come from? It strikes me that the human brain has evolved a necessary shortcut for doing so, and with some major implications.

Consider an animal (including a human) that has started eating some rotten, fetid, disgusting food. As a result, neurons in an area of the brain called the insula will activate. Gustatory disgust. Smell the same awful food, and the insula activates as well. Think about what might count as a disgusting food (say, taking a bite out of a struggling cockroach). Same thing.

Now read in the newspaper about a saintly old widow who had her home foreclosed by a sleazy mortgage company, her medical insurance canceled on flimsy grounds, and got a lousy, exploitative offer at the pawn shop where she tried to hock her kidney dialysis machine. You sit there thinking, those bastards, those people are scum, they’re worse than maggots, they make me want to puke… and your insula activates. Think about something shameful and rotten that you once did… same thing. Not only does the insula “do” sensory disgust; it does moral disgust as well. Because the two are so viscerally similar. When we evolved the capacity to be disgusted by moral failures, we didn’t evolve a new brain region to handle it. Instead, the insula expanded its portfolio.

Or consider pain. Somebody pokes your big left toe with a pin. Spinal reflexes cause you to instantly jerk your foot back — just as they would in, say, a frog. Evolutionarily ancient regions activate in the brain as well, telling you about things like the intensity of the pain, or whether it’s a sharp localized pain or a diffuse burning one. But then there’s a fancier, more recently evolved brain region in the frontal cortex called the anterior cingulate that’s involved in the subjective, evaluative response to the pain — is it a disaster — a piranha has just bitten you? Is it a disaster — the shoes you bought are a size too small? Is it great news — by enduring this pain, are you somehow saving the world?

Now instead, watch your beloved being poked with the pin. And your cingulate will activate, as if it were you in pain. There’s a neurotransmitter called Substance P that is involved in the nuts and bolts circuitry of pain perception. Administer a drug that blocks the actions of Substance P to people who are clinically depressed, and they often feel better, feel less of the world’s agonies. When humans evolved the ability to be wrenched with feeling the pain of others, where was it going to process it? Cram it into the anterior cingulate. And thus it “does” both physical and psychic pain.

Cleanliness is a truly interesting domain where the brain confuses the literal and metaphorical. In a remarkable study, Chen-Bo Zhong of the University of Toronto and Katie Liljenquist of Northwestern University demonstrated how the brain has trouble distinguishing between being a dirty scoundrel and being in need of a bath. Volunteers were asked to recall either a moral or immoral act in their past. Afterward, as a token of appreciation, Zhong and Liljenquist offered the volunteers a choice between the gift of a pencil or of a package of antiseptic wipes. And the folks who had just wallowed in their ethical failures were more likely to go for the wipes. In the next study, volunteers were told to recall an immoral act of theirs. Afterward, subjects either did or did not have the opportunity to clean their hands. Those who were able to wash were less likely to respond to a request for help (that the experimenters had set up) that came shortly afterward. Pontius Pilate wasn’t the only one to absolve his sins and lessen his imperative to act ethically by washing his hands.

This potential to manipulate behavior by exploiting the brain’s literal/metaphorical confusions about hygiene and health is also shown in a study by Mark Landau of the University of Kansas. Subjects either did or didn’t read an article about the health risks of airborne bacteria. All then read a history article that used imagery of a nation as a living organism with statements like, “Following the Civil War, the United States underwent a growth spurt.” Those who read about scary bacteria before thinking about the US as an organism were then more likely to express negative views about immigration.

Another example comes from a study by Lawrence Williams of the University of Colorado and John Bargh of Yale. Volunteers would meet one of the experimenters, believing that they would be starting the experiment shortly. In reality, the experiment began when the experimenter, seemingly struggling with an armful of folders, asks the volunteer to briefly hold their coffee. As the key experimental manipulation, the coffee was either hot or iced. Subjects then read a description of some individual, and those who had held the warmer cup tended to rate the individual as having a warmer personality (with no change in ratings of other attributes). And in a variant, volunteers were asked to hold either a heating or a cooling pad as part of some supposed study. Afterward, as a token of appreciation, subjects were offered a small gift certificate either made out to them or to a friend. Cold physical sensation, cold decision — keep the gift certificate for yourself.

Another brilliant study by Bargh and colleagues concerned haptic sensations (I had to look the word up — haptic: related to the sense of touch). Volunteers were asked to evaluate the resumes of supposed job applicants where, as the critical variable, the resume was attached to a clipboard of one of two different weights. Subjects who evaluated the candidate while holding the heavier clipboard tended to judge candidates to be more serious (with the weight of the clipboard having no effect on how congenial the applicant was judged). After all, we say things like how we understand weighty matters that reflect the gravity of a situation.

In another of their studies, the researchers, in their droll words, “primed participants by the seat of their pants.” Volunteers were seated in either a hard or soft chair. Seat someone in the former, and their strategy in a competition/cooperation game becomes more rigid. If clothes can make the man, chairs can make the hard-ass.

What to make of the brain processing literal and metaphorical versions of a concept in the same brain region, the problem of neural circuitry that doesn’t cleanly differentiate between the real and the symbolic? What are the consequences of the fact that evolution is a tinkerer and not an inventor, and has duct-taped metaphors and symbols to whichever pre-existing brain areas provided the closest fit?

Jonathan Haidt, of the University of Virginia, has shown how viscera and emotion often drive our decision-making, with conscious cognition mopping up afterward, trying to come up with rationalizations for that gut decision. The viscera that can influence moral decision-making and the brain’s confusion about the literalness of symbols can have enormous consequences. Part of the emotional contagion of the genocide of Tutsis in Rwanda arose from the fact that militant Hutu propagandists calling for the eradication of the Tutsi endlessly, iconically referred to them as “cockroaches.” Get someone to the point where his insula activates at the mention of an entire people, and he’s primed to join the bloodletting. Or consider the Indian Rebellion of 1857, which was led by sepoys — Hindu and Muslim soldiers in the British East India Company’s army. What triggered the uprising? The poor wages, the abuse from British officers, the very concept of colonial subjugation? Nah, none of those broke the camel’s back. Instead, it was rumors. In order to load their guns, sepoys had to bite the cartridges open, and Hindu sepoys were outraged by rumors that the cartridges were greased by the Brits with beef fat, a disgusting defilement of the sacred cow, while Muslim sepoys were convinced that cartridges were greased with lard, equally disgusting to them.

But if the brain confusing reality and literalness with metaphor and symbol can have adverse consequences, the opposite outcome can occur as well. At one juncture just before the birth of a free South Africa, Nelson Mandela entered secret negotiations with an Afrikaans general with death squad blood all over his hands, a man critical to the peace process because he led a large, well-armed Afrikaans resistance group. They met in Mandela’s house, the general anticipating tense negotiations across a conference table. Instead, Mandela led him to the warm, homey living room, sat beside him on a comfy couch, and spoke to him in Afrikaans. And the resistance melted away.

This neural confusion about the literal versus the metaphorical gives symbols enormous power, including the power to make peace. The economist/game theorist Robert Axelrod of the University of Michigan has emphasized this point in thinking about conflict resolution. For example, in a world of sheer rationality where the brain didn’t confuse reality with symbols, bringing peace to Israel and Palestine would revolve around things like water rights, placement of borders, and the extent of militarization allowed to Palestinian police. Instead, argues Axelrod, symbolic concessions of no material benefit will ultimately make all the difference. He quotes a Hamas leader who says that peace would come if Israel ever apologized for what happened to the Palestinians in 1948, admit they’d gotten screwed when European colonialists dealt with their guilt about the Jews by giving them someone else’s land. And he quotes senior Israeli officials saying, “We could have peace tomorrow if the Palestinians got anti-Semitic crap like the Protocols of the Elders of Zion out of their textbooks.”

Hope for true peace in the Middle East didn’t come with the news of a trade agreement being signed. It was when Mubarak of Egypt and Hussein of Jordan attended the funeral of the murdered Rabin, their heads covered with Jewish skullcaps. And for the Northern Irish, not when ex-Unionist demagogues and ex-IRA gunmen serve in a government together. It’s when those officials publicly commiserated about each other’s family misfortunes, or exchanged anniversary gifts. And famously for South Africans, not with successful negotiations about land reapportionment, but when black South Africa embraced rugby and Afrikaans rugby jocks sang the ANC national anthem.

Nelson Mandela was wrong when he advised, “Don’t talk to their minds; talk to their hearts.” He meant talk to their insulas and cingulate cortices and all those other confused brain regions, because that confusion could help make for a better world.

15 comments to This Is Your Brain on Metaphors

  • Barry McKenna

    Dr. Sapolsky, I have appreciated your work and insights for some time and turned my physician into a reader of your works. However, I am not sure about your essay’s suggested connection of the insula to shame. It is not that it seems unreasonable to me, but simply that organizations such as The Tomkins Institute ( and researchers like myself have been waiting for studies on shame to be taken up by the neuroscience community. Instead shame seems to be still limited to the psychological and sociological realms. If, instead, you can cite neuroscience papers on shame I’d be grateful.

  • Laurie Fraser

    Thanks for this, Dr Sapolsky – intriguing! I’ve been examining the virtual reification of religious symbolism generally, including iconography, metaphor and cultural practice, and your article puts an entirely new (for me, anyway) slant on things.

  • Metaphor also works on a social level, providing common, simple language for complex shared experience. The example of the flag you cite is a good example: it isn’t just triggering an individual response, but a collective one. I’d love to get a sense of how symbol-based neurology plays out in group situations, particularly in how symbols and metaphors can in fact help form groups — did the Hutus calling Tutsis cockroaches (or Nazis doing the same to Jews and Gypsies) help create social cohesion in creating a common symbolic language?

    I’m a cartographer, and interested in how the basic symbolic language of modern cartography creates a sense of commonality among map users. Cartography has come in for a fair amount of critique recently, mostly on the basis of the power structures it supports. What I find interesting in your approach, is that the old line that “the map is not the territory” is presumably to some extent contradicted by the neurology: I would expect that the part of the brain that interprets map is the same part that interprets actual landscape. Or that they overlap significantly. I’d love to know more about this.

  • Robert Goodrich

    This article speaks directly to an idea Mark Johnson puts forth in his book, The Meaning of the Body, which argues that the cognitive domain is inextricably linked to and dependent upon bodily processes. According this view, our higher level abstract thinking, which includes reasoning, logic, and conceptualization, is grounded in our bodily awareness and the dynamic coupling of our perceptual systems with the environment. As we develop, we learn that the world works in certain predictable ways, and we form associations between physical realities and abstract ones. These associations can be viewed as metaphors such as likening causality to a physical impact, i.e. we know that one ball striking another will cause the second ball to roll and thus understand when someone speaks of a “moving” speech really getting the campaign “rolling.” In short, Johnson claims, and I agree, that we owe our capacity for abstract reasoning to our embodied experience and the work of a tremendous array of neurons, which forms the physical substrate of the associations we call metaphors.

  • Right, see also work by George Lakoff, Rafael Nunez, and many others: embodied cognition, enactivism…

    A good book reviewing this work is Embodiment and Cognitive Science, by Raymond Gibbs, although it is already about 5 years out of date.

  • I have my doubts about the metaphoricity many of these phenomena (perhaps Dr. Sapolsky is using the word “metaphor” metaphorically!). Roman Catholics know their theology do not believe that the wafer and wine represent the body and blood of Christ — they believe that these things are literally the body and blood of Christ. Likewise, moral disgust, for example, is literally disgust.

    In my forthcoming book Less Than Human I argue that the dehumanizing imagery found in genocidal rhetoric is intended literally. The Nazis thought of Jews literally, not metaphorically. In fact, it is because these ideas are meant literally that they possess such immense destructive power. We are tempted to see dehumanizing speech as metaphorical because it is so deeply puzzling. How could a normal human being conceive of others as rats, cockroaches or dogs (to use three historically common examples)? In the book, I argue that we pull this off in much the same way that Catholics pull of their belief in the transformation of wafer and wine into flesh and blood. We unconsciously distinguish between essence and appearance. When we dehumanize others, we think of them as possessing a human appearance but a literally subhuman essence.

    • Mike M

      Professor Smith,
      Your response made me think of the work on metaphor that has been done by Donald Davidson and Richard Rorty. I’m just curious to know if you’ve looked at their work while doing your own.

  • Nicole

    I found your discussion of how visceral feelings of disgust processed in brain areas like the amygdala and frontal insula can add negative moral coloration to otherwise neutral stimuli to be very illuminating. I am interested in finding out more about the inverse phenomenon: how pleasurable feelings can make negative stimuli more “palatable.” I am interested in affect-laden intuitions through which mis-attributed pleasurable affective reactions can push people towards approach rather than avoidance. In particular, can associating events or activities with sexual pleasure override otherwise instinctive feelings of disgust? Can you (or others on this thread) suggest citations for scholarly investigations of this sort of affectively-mediated positive moral masking (to coin a term)?

  • John D

    Robert – I think your observation is remarkably insightful. To me, it helps fill a hole in our understanding of the evolution of this phenomena we call consciousness. It makes me wonder… does a dog, glancing at a bright sunset following a powerful rain storm, experience feelings of calm (or even hope)? Are all social animals metaphorical to some degree? Hmmmmmm.

  • Robert Sapolsky has written a wonderful, thoughtful essay on what appears to be an ever-growing component toward understanding what makes us special: the ability to employ earlier evolved, more visceral and basic cognitive capacities for the construction and use of ‘higher’ abstract concepts. I am familiar with the work on metaphor by Lakoff and Johnson, as relevant and noted by another commenter. Sapolsky has added thrilling neuroscience evidence and has brought in recent findings from experimental social psychology.

    I have a few follow-up questions. First, the insula and anterior cingulate were cited as two brain regions for which there is now evidence that evolution “has duct-taped metaphors and symbols to whichever pre-existing brain areas provided the closest fit.” The phenomena were for disgust and pain, respectively. Could we have here an example of convergent evolution in the sense that a similar general pattern has evolved (either biologically or culturally) in two different brain regions? (The pattern is, namely, the use of pre-existing brain dynamics to extend conceptualization into more abstract realms.) This might be something like intra-brain convergence of a cognitively successful pattern. If so, we might expect the same trick to occur elsewhere as well, linking other, different kinds of abstraction to other, different brain regions. Is this a possibility? Or, alternatively, could there be a master metaphor-making region that farms out the details to different brain regions as needed?

    Second, Steven Pinker in a recent PNAS paper says that the human ability for “metaphorical abstraction” is a second major ability (following the construction of a “cognitive niche”) that made us into who we are. This seems very much in lines with the strongest reading of Robert Sapolsky’s essay. The way I read the Pinker piece (and what makes sense to me) is that this metaphorical abstraction kicked online somewhat later than the constituent elements that went into constructing the cognitive niche, which allowed more basic cognitive capabilities (already within a specialized human realm) to eventually extend, say, reasoning that could sculpt stone tools into reasoning that could sculpt scientific theories. I wonder if RS sees as possible such a primary evolutionary role for this process of metaphorical abstraction.

    Finally, I turn to Sapolsky’s discussion of the recent experiments of Landau, Sullivan, and Greenberg. They found that test subjects exhibited increased out-group rejection on a larger, abstract scale (immigration issues within the U.S.) if they had been primed by reading about invasive bacteria. I wonder if RS thinks this finding might also involve the emotion of disgust and use the insula, or whether there are other brain regions as candidates to house the development of a basic biological rejection of some kind (there are presumably other types of aversion-drives) into more abstract but powerful aversive feelings towards some “them.”

    The issues Robert Sapolsky has raised in his essay are crucial to our future, as he shows in the final sections of his essay, with relevance across the scales of policy and politics in the quest for social justice and peace.

    Steven Pinker. Colloquium Paper: The cognitive niche: Coevolution of intelligence, sociality, and language. Proceedings of the National Academy of Sciences, 2010 107 (Supplement 2) 8993-8999; published ahead of print May 5, 2010, ldoi:10.1073/pnas.0914630107

  • Leigh Atchison

    I find it very interesting how the brain can be so manipulated by symbols we do not usually recognize. As humans I feel we would like to believe we have control over our actions, and ourselves. Robert Sapolsky, however, makes it clear that the environment of every situation we are in constantly manipulates us into doing what we do. It seems to me that the brain is much more of a subconscious organ than we realize. I am currently enrolled in the On the Human honors philosophy course at North Carolina State University and this idea of consciousness and unconsciousness is a common topic in our class. This idea that humans are not always aware of where our decisions come from would be a good topic of discussion because I think it would help expand on what we believe a person is and how it relates to all types of humans and even animals or machines.

    Sapolsky begins by claiming that the human brain is not all that complex, but I feel that the fact that we have these levels of consciousness and unconsciousness makes the human brain much more complex than any other animal’s. I find it intriguing though that our neurons are exactly identical to that of even the simplest of animals like the fruit fly. If the only difference between the human brain and other animals’ brains is the number of neurons, then it makes me wonder if evolution could eventually create non-human animals as complex as humans just by increasing their neuronal connections. This also leads me to believe we can determine the innermost complexities of the human brain because the answer must lie in the number of neurons. I also believe that understanding these complexities of the brain could lead to a better human civilization because we would understand how to better communicate and deal with each other as in the Middle East peace example given by Sapolsky.

  • Robert Sapolsky

    First, thank you all for the thoughtful and interesting responses; this confirms what was promised by the On The Human folks, namely that this is an enjoyable process.

    Everyone agreed about the extraordinary potential power of symbols and metaphors. This has been an area of intense research by psychologists, linguists and philosophers; Doug Holton, for example, cites the pioneering work by George Lakoff of Berkeley. This area has also caught the interest of cognitive scientists who think about the evolution of the human mind (reflected in Tyler Volk citing the work of Steven Pinker at Harvard, who has emphasized how the capacity for “metaphorical abstraction” helps define what is unique about humans). Robert Goodrich discusses the work of another pioneer, Mark Johnson of the University of Oregon. Johnson has explored how the human capacity for abstraction is shaped by the fact that the human brain does not spend its time floating in a vat of brain soup while thinking big thoughts. Instead, it is embodied.

    The power of symbols and metaphors is implicit in David Livingstone Smith writing about the difference between “A symbolically represents B” and “A is B.” For the devout Roman Catholic, wine in a particular context does not represent the blood of Christ; it is the blood. For a Hutu capable of slaughtering his neighbors without a twinge of remorse, Tutsi are not symbolic cockroaches; they are real ones. To use Smith’s term, the “metaphoricity” of metaphors can get lost in the viscera.

    My piece focused on the fact that human cognition and emotions are not only embodied, they are embrained. There are neurons filled with organelles, membranes, enzymes — real in-the-trenches cells that even generate yucky metabolic waste, cells that collectively consider whether life is indeed a bowl of cherries, or if the world really is made to go round by love.

    The key point of the piece was that these neurons and the brain regions in which they reside are not dedicated (“dedicated” in the sense of their sole job being to ponder symbols and metaphors from their oak-paneled studies). Instead, these neurons are working stiffs normally involved in quotidian mammalian tasks, who have gotten saddled with new functions because of the weirdness that is human brain evolution. And thus we wind up with human moral outrage potentially being so powerful because of the involvement of neurons that make you avoid eating maggot-riddled meat, or with the potential power of human empathy because of the involvement of neurons that decide that it is not a good thing that your knee hurts. In response to Tyler Volk’s question about the Landau et al. study that I discussed, I’ll bet that yes, “Don’t eat that maggot!” neurons in the insula are engaged in circumstances where our being primed about environmental pathogens makes us xenophobic.

    This raised some interesting questions about whether there are other domains where our brain intermingles something approximating the sacred and the profane. Barry McKenna wonders whether there are similar neurobiological insights regarding the power of shame. I’m not sure if there has been much work in this area, but there has been concerning guilt. For example, in a recently Epublished paper (Basile et al., Human Brain Mapping, 2010;, the authors study the neurobiology of “deontological” guilt (guilt derived from inner values) versus “altruistic guilt” (guilt derived from the judgments of others). They found that the two types of guilt do not engage the same brain circuits. Fascinatingly, it is deontological, but not altruistic guilt which activate the insula. We may feel embarrassment or regret when we violate some rule. But there is the must greater capacity to feel gut-wrenching disgust when we violate our own deeply held values.

    Nicole wondered if there something similar going on in the brain in the realm positive metaphors, when we can think of both a hot fudge sundae and a charming, wry movie comedy as being “delicious.” I think that is absolutely the case. Rather than involving disgust-ometer brain regions like the insula, there is involvement of regions that make heavy use of dopamine, a neurotransmitter central to pleasure and the anticipation of pleasure.

    Superficially, you might think of a map as a pretty straightforward objective document; instead, just as winners write the history, they also draw the maps. Nat Case wonders whether there is a similar convergent neural processing of the real and the metaphorical in cartography. Is “the part of the brain that interprets map…the same part that interprets actual landscape”? This seems likely to be at least partially true, insofar as a map is an imagined version of the real world. A large body of work pertinent to this by Stephen Kosslyn of Harvard explores how the brain perceives and imagines in similar ways (for a nice review, see Kosslyn 2005 Mental images and the brain. Cognitive Neuropsychology 22, 333). For example, in one study from his group, when subjects in a functional MRI brain scanner either perceived a visual pattern or imagined it, some of the same brain regions would be activated. Now it wouldn’t be all that surprising if higher-order associational brain regions (i.e., the world of fancy places like the anterior cingulate) were activated while a person was, say, either perceiving or imagining a painting of enormous emotional significance. But the same is happening in much simpler, more nuts and bolts brain regions — similar circuits of neural activity are evoked in the primary visual cortex whether a person is looking at or imagining squiggly-shaped stimuli of particular horizontal/vertical orientations.

    So the brain uses a similar trick of squeezing the concrete/literal and the metaphorical/symbolic in together in a number of different domains. Tyler Volk wonders if this reflects different brain regions independently converging on to the same solution, or whether there is a “master metaphor-making region [of the brain] that farms out the details to different brain regions as needed.” I vote for the former. The brain wonderfully reflects evolution as a tinkerer, where various brain regions independently stumbled onto similar solutions, rather than evolution as an inventor of (in this case) a brand-new top down brain region overseeing the metaphor show.

    In considering the evolution of the neural underpinning of metaphors and symbols, Volk in effect wonders about the adaptive advantages of such evolution. There have been huge numbers of ways where the Darwinian fitness of an individual in a social species has been enhanced by a moment of well-timed savagery (amid there being a similar number of ways in which copies of genes are passed on thanks to moments of altruism, empathy and cooperation). David Livingstone Smith, in his own writings, has emphasized the role of self-deception in some realms where the metaphor becomes as real as the real — it truly does take some heavy duty self-deception to convince yourself that you are killing a cockroach and not an innocent human.

    Again, thank you all for these comments.
    Robert Sapolsky

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