Discontinuities between Human and Animal Cognition

Premack offers a stimulating brief essay (PDF here) pointing out that recent cognitive studies finding abilities in animals once thought unique to humans should not lead us to confuse similarity with equivalence, for the human brain has nerve cell types and connections not found in any other animals. He examines eight cognitive areas to argue that dissimilarities are large. Here is his abstract:

Microscopic study of the human brain has revealed neural structures, enhanced wiring, and forms of connectivity among nerve cells not found in any animal, challenging the view that the human brain is simply an enlarged chimpanzee brain. On the other hand, cognitive studies have found animals to have abilities once thought unique to the human. This suggests a disparity between brain and mind. The suggestion is misleading. Cognitive research has not kept pace with neural research. Neural findings are based on microscopic study of the brain and are primarily cellular. Because cognition cannot be studied microscopically, we need to refine the study of cognition by using a different approach. In examining claims of similarity between animals and humans, one must ask: What are the dissimilarities? This approach prevents confusing similarity with equivalence. We follow this approach in examining eight cognitive cases—teaching, short-term memory, causal reasoning, planning, deception, transitive inference, theory of mind, and language—and find, in all cases, that similarities between animal and human abilities are small, dissimilarities large. There is no disparity between brain and mind.

Another major article on this topic is in draft form for Brain and Behavioral Sciences: "Darwin’s mistake: explaining the discontinuity between human and nonhuman minds," by Derek C. Penn, Keith J. Holyoak and Daniel J. Povinelli.
Their abstract:

Over the last quarter-century, the dominant tendency in comparative cognitive psychology has been to emphasize the similarities between human and nonhuman minds and to downplay the differences as “one of degree and not of kind” (Darwin 1871). In the present paper, we argue that Darwin was mistaken: the profound biological continuity between human and nonhuman animals masks an equally profound discontinuity between human and nonhuman minds. To wit, there is a significant discontinuity in the degree to which human and nonhuman animals are able to approximate the higher-order, systematic, relational capabilities of a physical symbol system (Newell 1980). We show that this symbolic-relational discontinuity pervades nearly every domain of cognition and runs much deeper than even the spectacular scaffolding provided by language or culture alone can explain. We propose a representational-level specification of where human and nonhuman animals’ abilities to approximate a PSS are similar and where they differ. We conclude by suggesting that recent symbolic-connectionist models of cognition shed new light on the mechanisms that underlie the gap between human and nonhuman minds.

Cooperation: a third basic principle of evolution.

Carl Zimmer writes an interesting profile of the work and ideas of Marin Nowak at Harvard in the July 31 NY Times Science section (PDF here). Here are some edited clips:

Nowak argues that cooperation is one of the three basic principles of evolution. The other two are mutation and selection. On their own, mutation and selection can transform a species, giving rise to new traits like limbs and eyes. But cooperation is essential for life to evolve to a new level of organization. Single-celled protozoa had to cooperate to give rise to the first multicellular animals. Humans had to cooperate for complex societies to emerge.

The article describes Nowak's work with models that are intellectual descendants of the Prisoner's Dilemma puzzle.

These models incorporate neighborhoods of players in which tight clusters of cooperators emerge, and defectors elsewhere in the network are not able to undermine their altruism. The emergence of cooperation is described with a simple equation: B/C>K. That is, cooperation will emerge if the benefit-to-cost (B/C) ratio of cooperation is greater than the average number of neighbors (K)...Nowak and his colleagues also pioneered a version of the Prisoner’s Dilemma in which players acquire reputations. They found that if reputations spread quickly enough, they could increase the chances of cooperation taking hold. Players were less likely to be fooled by defectors and more likely to benefit from cooperation.

Yawn to cool your brain?

A curious and slightly flakey bit: Eric Nagourney in Tuesday's Science section of the NY Times describes work by Gallup et al (PDF here) published in the Journal Evolutionary Psychology. It seems to me they might have actually measured brain temperature instead of just speculating about it. Nagourney notes the proposal by Gallup et al. that:

yawning... is a way for the body to cool the brain...volunteers yawned more often in situations in which their brains were likely to be warmer...To prove their theory that yawning regulates brain temperature when other systems in the body are not doing enough, the researchers took advantage of the well-established tendency of people to yawn when those around them do — the so-called contagious yawn...The volunteers were asked to step into a room by themselves and watch a video showing people behaving neutrally, laughing or yawning. Observers watching through a one-way mirror counted how many times the volunteers yawned...Some volunteers were asked to breathe only through their noses as they watched. Later, volunteers were asked to press warm or cold packs on their foreheads...“The two conditions thought to promote brain cooling (nasal breathing and forehead cooling) practically eliminated contagious yawning,” the researchers wrote.

The study may also help explain why yawning spreads from person to person...A cooler brain, Dr. Gallup said, is a clearer brain...So yawning actually appears to be a way to stay more alert. And contagious yawning, he said, may have evolved to help groups remain vigilant against danger.

Is there wisdom in disgust? - moral psychology

Dan Jones writes an interesting essay in a recent issue of Science (PDF here) on how work in evolutionary theory, moral philosophy, and neuroscience casts doubt on the idea that disgust embodies a deep-seated wisdom. Instead it provides an emerging portrait of an evolutionarily constrained emotion that is a poor guide to ethical action. Here are some edited clips from his article:

Although the experience of disgust feels primal, the emotion does not seem to be widespread in other animals. Many species exhibit distaste in response to the sensory properties of food — such as sourness and bitterness — and a monkey, cat or human infant might spit out something disagreeable. But only humans beyond infancy will reject food on the basis of where it might have been and what it might have touched.

A clue is the language of moral indignation itself...All cultures and languages that we have studied have at least one word that applies both to core disgust (cockroaches and faeces) and also to some kind of social offence, such as sleazy politicians or hypocrites...people labelled as disgusting in this way evoke fears of contamination just as rotting food does...disgust drives some moral judgements, but ... they are mainly those relating to behaviour that involves bodily fluids or contact — gay sex, for instance — rather than more abstract issues.

Clues suggest a physiological reality for moral disgust. Whereas anger pushes the heart rate up, being viscerally disgusted makes it drop. Experiments done by Haidt and Sherman showed
... people hooked up to a heart monitor video footage of morally negative but not viscerally disgusting behaviour, such as an American neo-Nazi meeting. The participants said that the video triggered disgust and anger, and on average their heart rates fell, not rose. What's more, those who reported increased clenching in their throat had a greater drop in heart rate, making the link with core disgust look stronger.
...this is the first physiological evidence that socio-moral disgust really is disgust and not just metaphor or anger.

Brain imaging studies might also point to an overlap between core and moral disgust... Moll...used magnetic resonance imaging (MRI) to monitor the flow of blood in the brains of 13 healthy adult volunteers as they mulled over situations evocative of core disgust and those that elicit self-reported moral disgust or indignation. He found that core and moral disgust recruit overlapping brain areas, particularly the lateral and medial orbitofrontal cortex, suggesting that the emotions are related. These regions of the brain are activated by unpleasant sensory stimuli, and they connect with other emotion-related areas, such as the amygdala.

Evolution suggests that the human moral faculty — the psychological systems that make judgements about right and wrong, what's permissible and what isn't — was cobbled together from pre-existing brain systems over millions of years of biological and cultural evolution. Along the way, it latched onto disgust as a useful tool...The experimental data point to the possibility that our disgust system might have been adapted by evolution to allow us to reject or disapprove of abstract concepts such as ideologies and political views that are deeply influenced by culture, as well social groups associated with 'disgusting' concepts...In making symbolic distinctions between us and them visceral, disgust could potentially foster greater cohesion within groups by bringing people together in defence against a common out-group...Disgust works for the group as it does for the individual — what is in the group is 'me' and what is not is 'not me'...Where core disgust is the guardian of the body, moral disgust acts as the guardian of social body — that's when disgust shows its ugliest side.

...disgust is an emotion we are stuck with. Heuser suggests that the challenge... is to make people more reflective about what they say and think. He cites the success that advocates of political correctness have had in lowering the prevalence of casually sexist and racist language. Moll suggests optimistically that cultivating cultural and personal values of tolerance and empathy could function as an antidote to the toxic effects of disgust...by thinking less with our guts, and more with our heads and hearts, we might be able push back the boundaries of our moral world.

As in this Figure, Beauty or beast: things that once disgusted can in new contexts be tolerated.

Genuine vs. Fake smiles, can you tell the difference?

This neat test from the BBC, based on Paul Ekman's work.

Dumb Blondes and Athletes, smart brains...

Robert Frank has a nice piece in the New York Times (PDF here) describing some recent sociology/economics articles. Why are there so many jokes about dumb blondes and athletes despite persuasive evidence that blondes and athletes are no less intelligent than others? First the dumb blonde joke:

A married couple were awakened by a call at 2 a.m. The wife, a blonde, picked up the phone, listened a moment and said, “How should I know, that’s 200 miles from here!” and hung up. Her husband asked, “Who was that?” She replied, “I don’t know; some woman wanting to know if the coast is clear.”

Now the dumb athlete joke:

Two offensive linemen in a rented boat catch an unusually large number of trout in a secluded cove. As they start back to the marina, one reaches over with his felt-tip pen and marks an X on the starboard bow. “I want to make sure we can find this spot again tomorrow,” he explained. “Idiot,” his friend replied, “what makes you think we’ll get the same boat?”

Actually the hypothesis that beauty (blondness is viewed as a positive characteristic in women) and brains to together is more likely:

(1) men generally place relatively greater emphasis on looks; (2) women generally place relatively greater emphasis on income and status. (3) more-intelligent men tend to achieve higher income and status; (4) both intelligence and physical attractiveness are traits with significant inheritable components...if both beauty and intelligence are inheritable, then the offspring of such unions will tend to display above-average values of both traits.

So why the dumb blonde and athlete jokes?

If blondes are perceived as more attractive, then being blond may create valuable opportunities that do not require onerous investments in education and training. The dumb blonde stereotype may thus stem from the fact that blondes rationally choose to invest less than others in education and other forms of human capital.

and,

...because gifted athletes enjoy many attractive social and employment opportunities that others do not, they may rationally choose to invest less, on average, in human capital.

The bottom line is that popular perceptions about the intelligence of blondes and athletes may stem more from the academic choices made by members of these groups and from choices that others make about them than from any innate differences in mental ability.

Evolution of human and animal personalities

Here is another editor's summary, and a PDF of the review by Bell of the work by Wolf et al. is here.

Although 'personalities' such as boldness, aggressive behaviour and risk avoidance have been shown to exist in more than sixty animal species, from primates to ants, explaining their existence in terms of evolution has been a puzzle. Surely, evolution should not favour the maintenance of different personalities, but rather the convergence towards a single one. In a numerical life-history model, Wolf et al. show that the evolution of animal personalities, defined as consistent sets of behaviours shown in a variety of contexts, is related to an adaptive response to life-history trade-offs. In this model, decisions on trade-offs between current and future reproduction condition the response of individuals to risky situations, and this may be the basis for animal personalities and their maintenance in populations.

In Wolf et al.'s model (from their abstract)

...some individuals put more emphasis on future fitness returns than others. Life-history theory predicts that such differences in fitness expectations should result in systematic differences in risk-taking behaviour. Individuals with high future expectations (who have much to lose) should be more risk-averse than individuals with low expectations. This applies to all kinds of risky situations, so individuals should consistently differ in their behaviour. By means of an evolutionary model we demonstrate that this basic principle results in the evolution of animal personalities. It simultaneously explains the coexistence of behavioural types, the consistency of behaviour through time and the structure of behavioural correlations across contexts. Moreover, it explains the common finding that explorative behaviour and risk-related traits like boldness and aggressiveness are common characteristics of animal personalities.

Evolution and Brain science shaping public discourse

I want to mention and pass on two recent Op-Ed columns of David Brooks in the New York Times. He has done a commendable job of learning the basic ideas in evolution and brain science and passing them on in a clear and palatable way.

Here are some clips from the first, titled "The Age of Darwin" (PDF here).

Once the Bible shaped all conversation, then Marx, then Freud, but today Darwin is everywhere... Scarcely a month goes by when Time or Newsweek doesn’t have a cover article on how our genes shape everything from our exercise habits to our moods. Science sections are filled with articles on how brain structure influences things like lust and learning. Neuroscientists debate the existence of God on the best-seller lists, while evolutionary theory reshapes psychology, dieting and literary criticism. Confident and exhilarated, evolutionary theorists believe they have a universal framework to explain human behavior...Creationists reject the whole business, but they’re like the Greeks who still worshiped Athena while Plato and Aristotle practiced philosophy. The people who set the cultural tone today have coalesced around a shared understanding of humanity and its history that would have astonished people in earlier epochs....According to this view, human beings, like all other creatures, are machines for passing along genetic code. We are driven primarily by a desire to perpetuate ourselves and our species.

The logic of evolution explains why people vie for status, form groups, fall in love and cherish their young. It holds that most everything that exists does so for a purpose. If some trait, like emotion, can cause big problems, then it must also provide bigger benefits, because nature will not expend energy on things that don’t enhance the chance of survival...Human beings, in our current understanding, are jerry-built creatures, in which new, sophisticated faculties are piled on top of primitive earlier ones. Our genes were formed during the vast stretches when people were hunters and gatherers, and we are now only semi-adapted to the age of nuclear weapons and fast food. Furthermore, reason is not separate from emotion and the soul cannot be detached from the electrical and chemical pulses of the body. There isn’t even a single seat of authority in the brain. The mind emerges (somehow) from a complex light show of neural firings without a center or executive. We are tools of mental processes we are not even aware of.

The second essay, "The Morality Line," (PDF here) comments on the rush to assign responsibility for the recent killings at Virginia Tech by Cho Seung-Hui.

...over the past few decades, neuroscientists, evolutionary psychologists and social scientists have made huge strides in understanding why people — even murderers — do the things they do...It’s important knowledge, but it’s had the effect of reducing the scope of the human self...in the realm of the new science, the individual is like a cork bobbing on the currents of giant forces: evolution, brain chemistry, stress and upbringing. Human consciousness is merely an epiphenomena of the deep and controlling mental processes that lie within...the killings at Virginia Tech happen at a moment when we are renegotiating what you might call the Morality Line, the spot where background forces stop and individual choice — and individual responsibility — begins. The killings happen at a moment when the people who explain behavior by talking about biology, chemistry and social science are assertive and on the march, while the people who explain behavior by talking about individual character are confused and losing ground...And it’s true. We’re never going back. We’re not going to put our knowledge of brain chemistry or evolutionary psychology back in the bottle. It would be madness to think Cho Seung-Hui could have been saved from his demons with better sermons...There still seems to be such things as selves, which are capable of making decisions and controlling destiny. It’s just that these selves can’t be seen on a brain-mapping diagram, and we no longer have any agreement about what they are.

Egalitarian motives in humans

Dawes et al. play some laboratory games that suggest important factors underlying the evolution of strong reciprocity and cooperation in humans, experiments that distinguish reward and punishment from egalitarian motives. Their abstract below and a PDF of the article here:

Participants in laboratory games are often willing to alter others' incomes at a cost to themselves, and this behaviour has the effect of promoting cooperation. What motivates this action is unclear: punishment and reward aimed at promoting cooperation cannot be distinguished from attempts to produce equality. To understand costly taking and costly giving, we create an experimental game that isolates egalitarian motives. The results show that subjects reduce and augment others' incomes, at a personal cost, even when there is no cooperative behaviour to be reinforced. Furthermore, the size and frequency of income alterations are strongly influenced by inequality. Emotions towards top earners become increasingly negative as inequality increases, and those who express these emotions spend more to reduce above-average earners' incomes and to increase below-average earners' incomes. The results suggest that egalitarian motives affect income-altering behaviours, and may therefore be an important factor underlying the evolution of strong reciprocity and, hence, cooperation in humans.

The Male-Warrior Hypothesis

Some clips from Van Vugt et al:

Evolutionary scientists argue that human cooperation is the product of a long history of competition among rival groups. There are various reasons to believe that this logic applies particularly to men. In three experiments, using a step-level public-goods task, we found that men contributed more to their group if their group was competing with other groups than if there was no intergroup competition. Female cooperation was relatively unaffected by intergroup competition. These findings suggest that men respond more strongly than women to intergroup threats. ..These findings fit nicely with an evolutionary hypothesis about specific male intergroup adaptations—the male-warrior hypothesis—and such evolved intergroup traits are likely to be reinforced through cultural processes, for example, during childhood socialization...Women's social psychology is likely to be shaped more strongly by different kinds of needs, such as defending their offspring and creating supportive social networks

The article's PDF can be downloaded HERE.

Innateness and culture in language evolution - a bit of heresy.

Kirby et al ask:

Although languages vary, they share many universal structural properties. Where do these universals come from? A great deal of research has proceeded under the assumption that this is essentially a biological question: that languages have the structure they do because of our innate faculty for acquiring and processing language.

They suggest:

...that there are serious problems with this orthodox evolutionary/biolinguistic approach. It treats language as arising from two adaptive systems, individual learning and biological evolution, but in doing so misses a third: cultural transmission. The surprising consequences of taking all three adaptive systems into account are that strong universals need not arise from strong innate biases, that adaptation does not necessarily imply natural selection, and that cultural transmission may reduce the selection pressure on innate learning mechanisms. Our conclusions call into question the existence of strongly constraining biological predispositions for language, and the prominence of adaptationist explanations for the structural properties of languages.

Here are two useful figures from the paper, and the details of the Bayesian model they use you can find in the PDF of the article.


Fig. 1. (Click to enlarge) The structure of language arises from the interactions between three complex adaptive systems. As individuals, we acquire language using learning mechanisms that are part of our biological endowment (characterized in this paper in terms of prior bias). This learning machinery acts as the mechanism by which language is transmitted culturally through a population of individuals over time. Ultimately, this process of cultural transmission leads to a set of language universals (which can be expressed as a distribution over types of languages). The relationship between learning machinery and consequent universals is nontrivial but can be uncovered using the framework developed here. Finally, the structure of languages that emerge from this process will affect the fitness of individuals using those languages, which in turn will lead to the biological evolution of language learners, closing the loop of interactions.


Fig. 2. (Click to enlarge). The link between biological predispositions and language structure. Genes (in combination with the nonlinguistic environment) give rise to mechanisms for learning and processing language. These determine our innate predispositions with respect to language (our prior linguistic bias). Bias is a property of an individual, but the (universal) structure of human language emerges from the interaction of many individuals over time. Therefore, cultural transmission bridges the link between bias and universals. Although genes code for bias, biological fitness will in part be governed by the extended phenotype (i.e., language structure). To understand language evolution, we must understand this linking mechanism.

Exploiting the moral impulse

Daniel Gilbert writes a nice OpEd piece in today's NY Times, titled "Compassionalte Commercialism" (He is the psychology professor at Harvard whose book "Stumbling on Happiness" I abstracted in a series of posts 6/29/2006.)

In an advertising campaign that began last week, Nissan left 20,000 sets of keys in bars, stadiums, concert halls and other public venues. Each key ring has a tag that says: “If found, please do not return. My next generation Nissan Altima has Intelligent Key with push-button ignition, and I no longer need these.”

This campaign is clever, but not particularly original.

It was 1997, and the man who was crouched on the sidewalk at 68th and Broadway in New York City was one of the most pathetic souls I’d ever seen. His limbs were twisted in what appeared to be arthritic agony and tears were streaming down his face. “Please,” he whimpered. “Please, somebody help me.”

Most passers-by did what they were named for, but my wife and I stopped. The man looked up. “Please,” he sobbed. “I just want to go home.” My hand needed no guidance from my brain as it reached into my wallet and extracted $10. “Thank you,” he said as I handed him the money. “Thank you so much.” My wife and I mumbled some embarrassed words and walked on.

We hadn’t gone a block when she tugged my sleeve. “Maybe we should have gotten him into a cab,” she said. “He could barely stand up. He might need help. We should go back to see.” My wife is the patron saint of lost kittens and there is no arguing, so we went back to see. And what we saw was our horribly crippled friend walking briskly and happily up 68th Street, opening the door to a late-model car, getting in and driving away after what was apparently a short day of theatrical work.

I know two things now that I didn’t know then.

First, I now know that my hand did what human hands were designed to do. Research suggests that we are hard-wired with a strong and intuitive moral impulse — an urge to help others that is every bit as basic as the selfish urges that get all the press. Infants as young as 18 months will spontaneously comfort those who appear distressed and help those who are having difficulty retrieving or balancing objects. Chimpanzees will do the same, though not so reliably, which has led scientists to speculate about the precise point in our evolutionary history at which we became the “hypercooperative” species that out-nices the rest.

The second thing I know now that I didn’t know then is that this was the most damaging crime I had ever experienced. Like most residents of large cities, I’d been a victim before — of burglary once, of vandalism several times. But this was different. The burglars and vandals had taken advantage of my forgetfulness (“Why didn’t I double lock the door?”) and taught me to be better.

But the actor on 68th Street had taken advantage of my helpfulness and taught me to be worse. The hand that had automatically reached for my wallet had been slapped, and once slapped was twice shy. I’ve never again given money to a stranger without scrutinizing him for the signs that distinguish suffering from its imitation. And because I don’t know what those signs are, I typically just walk by.

Now corporate America has taken a lesson from the guild of shameless grifters. Nissan’s plan to leave those 20,000 sets of keys in public venues is every bit as crafty as the fraudulent performance that a decade ago left me with holes in both my pocketbook and soul. There is no selfish reason to bend down and pick up a key ring, but Nissan knows that we will bend without thinking because the impulse to help is bred into our marrow. Our best instinct will be awakened by a key ring and then punished by a commercial. Like rubes throughout the ages, we will be lured by a false cry of distress and quickly cured of our innocence and compassion.

We are used to commercial tricks that play on our fears. The official-looking letter marked “Verification Audit” is actually a magazine subscription renewal form; the credit card company’s ominous call to “discuss your account” is actually an attempt to sell new services.

Should we now get used to commercial tricks that play on our humanity? How would we feel about a device planted in trash bins that screams “I’m stuck!” until the lid is opened, at which point it continues, “Stuck in a dead end job, that is — and if you are too, then let us show you how to make millions in real estate with no money down”? Is it O.K. to send a thousand doleful puppies into the streets with tags that say: “Thanks for checking. And speaking of checking, our bank charges no monthly fees”?

What happens to us when greed masquerades as need, when cries for help become casting calls for chumps, when our most noble actions make us patsies? “You put an idea out there and seed it,” said the president of the advertising agency that came up with Nissan’s key ring ploy. “And people carry it for you.” Indeed they do. The idea being seeded and carried in this case is that the world cries wolf, that our moral impulse betrays us and that smart people should keep on walking.

Most laughing has little to do with humor...

A nice piece by John Tierney (PDF download here) in the NY Times points out that

It’s an instinctual survival tool for social animals, not an intellectual response to wit. It’s not about getting the joke. It’s about getting along.

I recommend that you also have a look at an engaging article by Panksepp and Burgdorf: ‘‘Laughing’’ rats and the evolutionary antecedents of human joy? (PDF download here)

Why do we believe - Darwin’s God

Credit: New York Times

The New York Times Sunday Magazine of 3/4/07 contains an interesting article by Robin Marantz Henig on why:

...there seems an inherent human drive to believe in something transcendent, unfathomable and otherworldly, something beyond the reach or understanding of science...The debate over why belief evolved is between byproduct theorists and adaptationists.

Byproduct Theorists:

Darwinians who study physical evolution distinguish between traits that are themselves adaptive, like having blood cells that can transport oxygen, and traits that are byproducts of adaptations, like the redness of blood. There is no survival advantage to blood’s being red instead of turquoise; it is just a byproduct of the trait that is adaptive, having blood that contains hemoglobin.

Something similar explains aspects of brain evolution, too, say the byproduct theorists...Hardships of early human life favored the evolution of certain cognitive tools, among them the ability to infer the presence of organisms that might do harm, to come up with causal narratives for natural events and to recognize that other people have minds of their own with their own beliefs, desires and intentions. Psychologists call these tools, respectively, agent detection, causal reasoning and theory of mind (or folk psychology). [See Atran, “In Gods We Trust: The Evolutionary Landscape of Religion,” 2002.]

Folkpsychology, as Atran and his colleagues see it, is essential to getting along in the contemporary world, just as it has been since prehistoric times. It allows us to anticipate the actions of others and to lead others to believe what we want them to believe; it is at the heart of everything from marriage to office politics to poker...The process begins with positing the existence of minds, our own and others’, that we cannot see or feel. This leaves us open, almost instinctively, to belief in the separation of the body (the visible) and the mind (the invisible). If you can posit minds in other people that you cannot verify empirically, suggests Paul Bloom, a psychologist and the author of “Descartes’ Baby,” published in 2004, it is a short step to positing minds that do not have to be anchored to a body. And from there, he said, it is another short step to positing an immaterial soul and a transcendent God.

The bottom line, according to byproduct theorists, is that children are born with a tendency to believe in omniscience, invisible minds, immaterial souls — and then they grow up in cultures that fill their minds, hard-wired for belief, with specifics. It is a little like language acquisition, Paul Bloom says, with the essential difference that language is a biological adaptation and religion, in his view, is not. We are born with an innate facility for language but the specific language we learn depends on the environment in which we are raised. In much the same way, he says, we are born with an innate tendency for belief, but the specifics of what we grow up believing — whether there is one God or many, whether the soul goes to heaven or occupies another animal after death — are culturally shaped...

The Adaptationists:

Trying to explain the adaptiveness of religion means looking for how it might have helped early humans survive and reproduce. As some adaptationists see it, this could have worked on two levels, individual and group. Religion made people feel better, less tormented by thoughts about death, more focused on the future, more willing to take care of themselves. As William James put it, religion filled people with “a new zest which adds itself like a gift to life . . . an assurance of safety and a temper of peace and, in relation to others, a preponderance of loving affections.”

Such sentiments, some adaptationists say, made the faithful better at finding and storing food, for instance, and helped them attract better mates because of their reputations for morality, obedience and sober living. The advantage might have worked at the group level too, with religious groups outlasting others because they were more cohesive, more likely to contain individuals willing to make sacrifices for the group and more adept at sharing resources and preparing for warfare.

One of the most vocal adaptationists is David Sloan Wilson, an occasional thorn in the side of both Scott Atran and Richard Dawkins. Wilson, an evolutionary biologist at the State University of New York at Binghamton, focuses much of his argument at the group level. “Organisms are a product of natural selection,” he wrote in “Darwin’s Cathedral: Evolution, Religion, and the Nature of Society,” which came out in 2002...Through countless generations of variation and selection, [organisms] acquire properties that enable them to survive and reproduce in their environments. My purpose is to see if human groups in general, and religious groups in particular, qualify as organismic in this sense.”

Dawkins once called Wilson’s defense of group selection “sheer, wanton, head-in-bag perversity.” Atran, too, has been dismissive of this approach, calling it “mind blind” for essentially ignoring the role of the brain’s mental machinery. The adaptationists “cannot in principle distinguish Marxism from monotheism, ideology from religious belief,” Atran wrote. “They cannot explain why people can be more steadfast in their commitment to admittedly counterfactual and counterintuitive beliefs — that Mary is both a mother and a virgin, and God is sentient but bodiless — than to the most politically, economically or scientifically persuasive account of the way things are or should be.”

So,

What can be made of atheists, then? If the evolutionary view of religion is true, they have to work hard at being atheists, to resist slipping into intrinsic habits of mind that make it easier to believe than not to believe. Atran says he faces an emotional and intellectual struggle to live without God in a nonatheist world, and he suspects that is where his little superstitions come from, his passing thought about crossing his fingers during turbulence or knocking on wood just in case. It is like an atavistic theism erupting when his guard is down. The comforts and consolations of belief are alluring even to him, he says, and probably will become more so as he gets closer to the end of his life. He fights it because he is a scientist and holds the values of rationalism higher than the values of spiritualism.

This internal push and pull between the spiritual and the rational reflects what used to be called the “God of the gaps” view of religion. The presumption was that as science was able to answer more questions about the natural world, God would be invoked to answer fewer, and religion would eventually recede. Research about the evolution of religion suggests otherwise. No matter how much science can explain, it seems, the real gap that God fills is an emptiness that our big-brained mental architecture interprets as a yearning for the supernatural. The drive to satisfy that yearning, according to both adaptationists and byproduct theorists, might be an inevitable and eternal part of what Atran calls the tragedy of human cognition.

Getting past "mind bugs"

From Mahzarin Banaji, Psychology Department at Harvard:

I am bullish about the mind's ability to unravel the beliefs contained within it—including beliefs about its own nature...the ability of humans everywhere to go against the grain of their own beliefs that are familiar, that feel natural and right, and that appear to be fundamentally true...

We've done this sort of unraveling many times before, whether it is about the relationship of the sun to the earth, or the relationship of other species to us. We've put aside what seemed natural, what felt right, and what came easily in favor of the opposite. I am optimistic that we are now ready to do the same with questions about the nature of our own minds. From the work of pioneers such as Herb Simon, Amos Tversky, and Danny Kahneman we know that the beliefs about our own minds that come naturally, feel right, and are easy to accept aren't necessarily true. That the bounds on rationality keep us from making decisions that are in our own interest, in the interest of those we love, in the long-term interest of our societies, even the planet, even perhaps the universe, with which we will surely have greater opportunity to interact in this century.

Here are some examples of what seems natural, feels right, and is easy to believe in—even though it isn't rational or true.

We irrationally anchor: ask people to generate their social security number and then the number of doctors in their city and the correlation between the two numbers will be significantly positive, when in fact it ought to be zero—there's no relation between the two variables. That's because we can't put the first one aside as we generate the second.

We irrationally endow: give somebody a cheap mug, and once it's "my mug" through ownership (and nothing else) it becomes, in our minds, a somewhat less cheap mug. Endowed with higher value, we are likely to demand a higher price for it than it is worth or is in our interest to demand.

We irrationally see patterns where non exist: Try to persuade a basketball player, fan, or statistician that there isn't anything to the idea of streak shooting; that chance is lumpy and that that's all there is to Michael Jordan's "hot hand".

...such "mind bugs" extend to the beliefs and preferences we have about ourselves, members of our own social groups, and those who sit farther away on a scale of social distance....We don't intend to discriminate or treat unfairly, but we do....The ability to think about one's own long range interest, to self-regulate and delay gratification, to consider the well-being of the collective, especially to view the collective as unbounded by religion, language, or nationality requires a mental leap that isn't natural or easy. And yet each new generation seems to be able to do it more successfully than the previous one...old beliefs come unraveled because such unraveling is in our self-interest...we unravel existing beliefs and preferences because we wish them to be in line with our intentions and aspirations and recognize that they are not. I see evidence of this everywhere—small acts to be the person one wishes to be rather than the person one is—and it is the constant attempt at this alignment that gives me optimism.

A new description of our inner lives....

I rarely mention my internal experience and sensations on this blog - first, because I have viewed readers as "wanting the beef," objective stuff on how minds work. Second and more important, because my experience of noting the flow of my brain products as emotion laced chunks of sensing/cognition/action - knowing the names of the neurotransmitters and hormones acting during desire, arousal, calming, or affiliation - strikes me as a process which would feel quite alien to most people. Still, if we are materialists who believe that someday we will understand how the brain-body generates our consciousness and sense of a self, we will be able to think in terms like the following (a quote taken from Larissa MacFarquhar's profile of Paul and Patricia Churchland in the Feb. 12 New Yorker Magazine):

"...he and Pat like to speculate about a day when whole chunks of English, especially the bits that consitute folk psychology, are replaced by scientific words that call a thing by its proper name rather than some outworn metaphor... as people learn to speak differently they will learn to experience differently, and sooner or later even their most private introspections will be affected. Already Paul feels pain differently than he used to: when he cut himself shaving now he fells not "pain" but something more complicated - first the sharp, superficial A-delta-fibre pain, and then a couple of seconds later, the sickening, deeper feeling of C-fibre pain that lingers. The new words, far from being reductive or dry, have enhanced his sensations, he feels, as an oenophile's complex vocabulary enhances the taste of wine."

"Paul and Pat, realizing that the revolutionary neuroscience they dream of is still in its infancy, are nonetheless already preparing themselve for this future, making the appropriate adjustments in their everyday conversation. One afternoon recently, Paul says, he was home making dinner when Pat burst in the door, having come straight from a frustrating faculty meeting. "She said, 'Paul, don't speak to me, my serotonin levels have hit bottom, my brain is awash in glucocortocoids, my blood vessels are full of adrenaline, and if it weren't for my endogenous opiates I'd have driven the car into a tree on the way home. My dopamine levels need lifting. Pour me a Chardonnay, and I'll be down in a minute.' " Paul and Pat have noticed that it is not just they who talk this way - their students now talk of psychopharmacology as comfortably as of food."

Human Nature Redux

David Broder writes an Op-Ed piece with this title in the 2/18/07 Sunday NY Times, noting how public consciousness has shifted away from a belief in the essential goodness of human nature. "As Steven Pinker has put it, Hobbes was more right than Rousseau.....human beings are not as pliable as the social engineers imagined. Human beings operate according to preset epigenetic rules, which dispose people to act in certain ways. We strive for dominance and undermine radical egalitarian dreams. We’re tribal and divide the world into in-groups and out-groups...This darker if more realistic view of human nature has led to a rediscovery of different moral codes and different political assumptions. Most people today share what Thomas Sowell calls the Constrained Vision, what Pinker calls the Tragic Vision and what E. O. Wilson calls Existential Conservatism. This is based on the idea that there is a universal human nature; that it has nasty, competitive elements; that we don’t understand much about it; and that the conventions and institutions that have evolved to keep us from slitting each other’s throats are valuable and are altered at great peril."

" Today, parents don’t seek to liberate their children; they supervise, coach and instruct every element of their lives. Today, there really is no antinomian counterculture — even the artists and rock stars are bourgeois strivers. Today, communes and utopian schemes are out of favor. People are mostly skeptical of social engineering efforts and jaundiced about revolutionaries who promise to herald a new dawn. Iraq has revealed what human beings do without a strong order-imposing state....This is a big pivot in intellectual history. The thinkers most associated with the Tragic Vision are Isaiah Berlin, Adam Smith, Edmund Burke, Alexander Hamilton, James Madison, Friedrich Hayek and Hobbes. Many of them are conservative...And here’s another perversity of human nature. Many conservatives resist the theory of evolution even though it confirms many of conservatism’s deepest truths."

Body Hot Spots

I just came across a complete web version of this book by R. Dale Guthrie which I enjoyed reading in the 1970s. Its perspective on the mixes of behavior and anatomy that comprise our social organs continues to be an original one.

Happiness and human evolution...

I've done some posts on defining happiness and how important social intimacy might or might not be. Several major magazines, including the Economist and the New York Times Magazine, have recently presented articles on research directed towards defining what happiness might in fact consist of, and a number of new university courses have the study of happiness as their main subject (see "Happiness 101, by D.T. Max). The distinction is frequently made between feeling good (the hedonic treadmill) and doing good. The former creates a hunger for more pleasure while the latter is suggested to be more likely to lead to lasting happiness.

My take on the fact that we frequently experience warm feelings after doing good is that we are experiencing the activation of our evolved affiliative neuro-endrocine repertoire, which has components like the release the neuropeptide oxytocin that promotes bonding and trust (see Feb. 13 post). There seems an obvious evolutionary rationale for the pleasure we take in helping others: groups of humans who develop this trait more highly might be more cooperative and effective in competition with other groups of humans whose members treat each other less sweetly. This, like all evolutionary psychology explanations, is hard to test or prove and thus criticized as pseudoscientific hand waving, but I like it. (There does seem to be a consensus that a major engine driving hominid evolution over the past several hundred thousand years has been competition between groups of humans.)

Such a group selection rationale can be applied also to why humans invent religions (which draw caustic blog posts from dry rationalists)...they wage war against other groups of humans more effectively. I do think David Sloan Wilson has it right on the central importance of group selection to human evolution. Have a look at his article "Testing major evolutionary hypothesis about religion with a random sample" which, along with several of this other recent interesting articles can be downloaded in PDF form from his website. I completely fail to understand the objection of the selfish-gene purists to group selection. Their points are now finding some refutation in mathematical models (cf. Bowles) that show how groups with altruistic genes might be better at waging war.

The evolution of cooperation: why the whites of our eyes are large.

Michael Tomasello, co-director of the Max Planck Institute for Evolutionary Anthropology in Leipzig, offers an interesting speculation in a brief essay in the Op-Ed section of the Jan. 13 New York Times. Because the whites of our human eyes are large we can easily detect the direction of another person's gaze even if their head is pointing slightly away from us. In contrast, neither chimpanzees nor any of the other 220 species of nonhuman primates have whites of the eyes that can be easily seen, making it much harder to see if their eyes are looking in a direction other than the one in which their heads are pointing.

Tomasello: "Evolutionary theory tells us that, in general, the only individuals who are around today are those whose ancestors did things that were beneficial to their own survival and reproduction. If I have eyes whose direction is especially easy to follow, it must be of some advantage to me...If I am, in effect, advertising the direction of my eyes, I must be in a social environment full of others who are not often inclined to take advantage of this to my detriment — by, say, beating me to the food or escaping aggression before me. Indeed, I must be in a cooperative social environment in which others following the direction of my eyes somehow benefits me."

"our research team has shown that even infants — at around their first birthdays, before language acquisition has begun — tend to follow the direction of another person’s eyes, not their heads. Thus, when an adult looked to the ceiling with her eyes only, head remaining straight ahead, infants looked to the ceiling in turn. However, when the adult closed her eyes and pointed her head to the ceiling, infants did not very often follow."

"Our nearest primate relatives, the African great apes (chimpanzees, bonobos and gorillas) showed precisely the opposite pattern of gaze following. When the human pointed her eyes only to the ceiling (head remaining straight ahead), they followed only rarely. But when she pointed her head only (eyes closed) to the ceiling, they followed much more often."

"It has been repeatedly demonstrated that all great apes, including humans, follow the gaze direction of others. But in previous studies the head and eyes were always pointed in the same direction. Only when we made the head and eyes point in different directions did we find a species difference: humans are sensitive to the direction of the eyes specifically in a way that our nearest primate relatives are not. This is the first demonstration of an actual behavioral function for humans’ uniquely visible eyes."

"Why might it have been advantageous for some early humans to advertise their eye direction in a way that enabled others to determine what they were looking at more easily? One possible answer, what we have called the cooperative eye hypothesis, is that especially visible eyes made it easier to coordinate close-range collaborative activities in which discerning where the other was looking and perhaps what she was planning, benefited both participants...If we are gathering berries to share, with one of us pulling down a branch and the other harvesting the fruit, it would be useful — especially before language evolved — for us to coordinate our activities and communicate our plans, using our eyes and perhaps other visually based gestures....Infant research, too, suggests that coordinating visual attention may have provided the foundation for the evolution of human language. Babies begin to acquire language through joint activities with others, in which both parties are focused on the same object or task. That’s the best time for an infant to learn the word for the object or activity in question."