Pinker, How the Mind Works. W.W. Norton,
New York, 1997.
Reviewed by John Bedell, with a Discourse on Evolutionary Psychology
The shelves of my public library are getting crowded now with the works of various would-be Goulds and Sagans. At first I was excited by all the new science titles, but I have to say that most of these books are just plain bad. Mediocrity creeps into everything, and as any bandwagon gets going a load of losers tries to jump on for the ride. Here is a book, though, that I can recommend without reservation to anyone interested in the mind. How the Mind Works is an order of magnitude better than anything else I have read on the subject: it is lively, funny, full of great examples and strange facts, and it explains things wonderfully. Ever wonder how Magic Eye stereograms actually work? Why it is so hard to make a robot that can see, walk, or think like a person? What a neural network is, and how the ones theorists play with are different from real neurons? Pinker explains all these and much more.
Pinker's subject is the computational model of the brain. Like most in his field, he thinks that the ancient question of how a metaphysical substance like mind could be produced by brute matter has been solved by information theory. Information is a metaphysical substance like mind, but now we understand perfectly well how information can be encoded and manipulated in the material world; that, after all, is what every computer does. The brain, in this view, is an information processing machine like a computer, and mind is the result of its operations. Pinker is also engaged in a debate within the fraternity of mind scholars, over how much structure is built into the brain at birth. Some experts think the brain is just a big neural net, and that almost everything about its programming is learned after birth. Pinker believes that the brain contains many sub-routines, as it were, that are programmed in detail by our genes. He thinks we have a special brain module for learning language, another for recognizing faces, and so on, and he looks to understand the mind through analyzing the details of these sub-programs.
It is, says Pinker, through the application of information theory and artificial intelligence research that the study of the mind has made such rapid progress in recent decades. In one way our familiarity with computers has increased our amazement with the mind, because the mind can do things that nobody ever thought were amazing until people tried to teach computers to do the same thing. For example, machine vision is still extremely primitive, because no engineer has yet figured out how to make a robot formulate a three-dimensional understanding of the world based on a two-dimensional image. The mathematical problem is unsolvable; there is simply no algorithm to make the conversion. Animals do this by means of assumptions about the world, some inherited and some learned-- the existence of these assumptions is the reason we can be fooled by optical illusions-- but the tricks involved are still far beyond our understanding. Another good example is what philosophers now call the "framing problem." How does your brain know what set of information to draw on to make any particular decision? Obviously, we can't consider everything we know, and we can't consider every possible outcome of our decision. How we draw these limits, though, remains a mystery.
But, anyway, if you want to learn about that sort of stuff, read How the Mind Works. What I want to write about today is evolutionary psychology: the study of how natural selection might have built the human brain, and how the kinds of stresses that shaped our evolution as hunter-gatherers might be influencing our lives and thoughts today. Evolutionary psychology has become one of America's favorite parlor games, and almost anybody can play: women cruise flea markets because of their inborn tendency to gather nuts and berries, while men prefer car shopping because they evolved to hunt big game. Pinker is too intelligent for that sort of baloney, but he is convinced that the fundamental structures of our brains were evolved to enable hunter-gatherers to survive and reproduce, and he is always looking for legacies of that evolutionary struggle.
Pinker makes several arguments that I find interesting. He questions whether we will ever understand problems like the origin of consciousness and the purpose of the universe, because he does not think the brain evolved to answer every kind of question; problems too far removed from what we needed to do to survive on the savannah may simply be beyond our capability. He deals brilliantly with the adaptive function of emotions, using the Doomsday Machine from Dr. Strangelove to show the possible value of extreme passions that lead us into absurd, self-destructive acts. And he gives, along the way, what I think is the most convincing treatment I have ever read of the ethical issues that grow out of the evolutionary approach to human behavior.
The subject of evolutionary psychology is, after all, a touchy one. Pinker mentions several of the violent responses that have come out of left-wing and religious circles in the past couple of decades. The "Seville Statement", crafted by twenty social scientists and adopted by UNESCO, says, among other things,
It is scientifically incorrect to say that we have inherited a tendency to make war from our animal ancestors.Now these are topics, it seems to me, that ought to be established by research rather than by debates at UNESCO, but the political response to these questions is at least as common as the rational one. In Woman: An Intimate Geography Natalie Angier wages a tribe by tribe struggle against the sort of evolutionist who sees a past of violent struggle and male dominance: for every people among whom violent male competition is key, she offers another where cooperation among women is vital. She works especially hard to find ethnographic evidence for the importance of grandmothers.
Why do people care so much? Why does the question of whether our behavior has evolved evoke such violent responses in some quarters? The violence of these disagreements, as Pinker says, comes from a fundamental confusion of is and ought. The notion of genes for violence disturbs us because we connect, at a deep level, what is natural with what is good. If men evolved to cheat on their wives, the arguments goes, it must be ok for them to do so; or, maybe, we can't let people find out that men evolved to cheat because some of them will take this as license to do so. Pinker says,
I think moralistic science is bad for morals and bad for science. Surely paving Yosemite is unwise, Gordon Gecko is bad, and Mother Teresa is good, regardless of what came out in the latest biology journals.Amen! If what is natural is good, then it is good to die in measles epidemics, endure periodic famines, and suffer from intestinal parasites. The morality of our ancestral hunter gatherers is no more a fit guide for our behavior than their economies are a fit rulebook for the Federal Reserve. If most tribes ignore or abuse their elders, does that mean it is ok for us to lock ours in cheap nursing homes? Not to me. I take it as a given that young men are equipped by nature for violence, but that doesn't keep me from thinking that almost all violence is bad; instead, I take our inborn tendency toward violence as a call to increased efforts in the direction of pacifism. Our efforts to change the world are rarely helped by denying what the world is really like.
Pinker even offers, as an antidote to the most cynical sort of genetic thinking, what he calls "a more hopeful way of reflecting on the selfish gene":
The body is the ultimate barrier to empathy. Your toothache simply does not hurt me the way it hurts you. But genes are not imprisoned in bodies; the same gene lives in the bodies of many family members at once. The dispersed copies of a gene call to one another by endowing bodies with emotions. Love, compassion, and empathy are invisible fibers that connect genes in different bodies. They are the closest we will ever come to feeling someone else's toothache. When a parent wishes she could take the place of a child about to undergo surgery, it is not the species or the group or her body that wants her to have that most unselfish emotion: it is her selfish genes.The world is the way it is regardless of how we feel about it. If the study of human evolution turns up truths that we find morally disturbing, we cannot simply sweep those truths under the rug, expunge them from textbooks, and put on our most serious faces while we lie to our children about them. We must find more productive ways to think about evolutionary heritage, and we must, no matter what, continue our struggle to make our world a better, kinder, more forgiving place.
"Doubt is not a pleasant condition, but certainty is an absurd one"