What Darwin Got Wrong by Jerry Fodor and Massimo Piattelli-Palmarini (Profile Books, £20)
When Jerry Fodor says that Darwin is wrong, a lot of people will sit up and take notice. Fodor isn’t some religious crank, but one of the most respected figures in the academic world: a prolific author, professor of philosophy and founding father of the discipline of cognitive science. His reputation, however, is likely to be dented by this latest book. Fodor has a successful record as a controversialist, but in taking on Darwin he has bitten off more than he can chew.
Fodor isn’t the kind of thinker you would expect to oppose Darwinism. He has devoted his life to arguing that the human mind is a finely structured machine. His work straddles philosophy and psychology. As Fodor sees it, the human mind is best viewed as an innately structured digital computer. It may not be made of silicon chips, but it works in essentially the same way, with the help of a wide range of inbuilt “programmes” and “databases.”
Readers of the London Review of Books and the Times Literary Supplement will know that Fodor has a variety of interests and an enviable prose style. What Darwin got Wrong displays his characteristic punchiness and fondness for a throwaway line. He may have a co-author in Massimo Piattelli-Palmarini, but the prose bears Fodor’s stamp throughout. Presumably Piattelli-Palmarini, a biologist turned cognitive scientist, was brought in to add biological verisimilitude. In any case, the style and the biological facts may be fine, but the argument is no good.
Fodor and Piattelli-Palmarini’s target is natural selection, not evolution. They are happy to accept that life on earth has a common ancestry. After all, as they tell us, they are both fully paid-up materialist atheists. It is Darwin’s specific theory of the mechanism responsible for evolution that they don’t like. They deny that natural selection drives evolution by favouring those organisms that are well adapted to their environments.
They have two objections to natural selection. The first is familiar. Following the lead of the late Stephen Jay Gould, they point out that any number of biological traits, from the shape of the panda’s thumb to our own troublesome appendixes, are forced on us by history rather than any adaptive shaping of organisms to environment. Natural selection can only tinker with pre-existing designs, and so is often stuck with historical hangovers. This point is relatively uncontentious. While there is room to debate its importance, even ultra-Darwinists like Daniel Dennett and Richard Dawkins devote much discussion to the fact that natural selection is often constrained by the materials it is given to work with.
Fodor and Piattelli-Palmarini’s second objection is much more peculiar. Not only does natural selection fail to explain everything—it doesn’t explain anything. It never selects traits because they help organisms to survive. This goes far beyond Stephen Jay Gould, and indeed it is hard to take seriously. If Fodor and Piattelli-Palmarini are right, polar bears don’t have white fur because it confers advantages in the Arctic; we don’t have eyes because they help us to see; and in general there is no tendency for natural selection to preserve adaptive traits.
Fodor and Piattelli-Palmarini do have an argument for these strange claims. They say that natural selection is insensitive to the difference between good traits and bad ones. One of their central examples is the evolution of the heart. Hearts pump blood, but they also make thumping sounds. As a result, any selective mechanism that favours blood pumpers will willy-nilly favour noise makers too—and, while blood pumping may help survival, thumping noises are themselves unhelpful. So, they conclude, selection favours unhelpful traits as well as good ones.
It is hard to know what to say. This isn’t a good argument because, at its centre, lies a simple confusion. It is true that when an adaptive and a nonadaptive trait are tightly yoked together, natural selection will be forced to take them both or not at all, and so in these specific cases will be “blind” to the difference. But it doesn’t follow that there is no relevant difference at all between the two traits in question. Of course there is. One trait helps survival and the other doesn’t. And in general natural selection certainly isn’t blind to this kind of contrast. Organisms with helpful traits tend to leave more offspring than those without. This means that there is a general tendency for helpful traits to spread, even if unhelpful traits like thumping sounds sometimes come along for the ride.
When Fodor gave his argument a dry run in the London Review of Books a couple of years ago, it was greeted with bewilderment. Could he really be saying that polar bears aren’t white because it hides them in the snow? And it wasn’t only the ultra-Darwinists who objected. Even the usual Darwin-bashers took pains to distance themselves from his views. It takes a lot to get Steven Rose, the editor of Alas Poor Darwin, on the same side as Daniel Dennett, but Fodor managed it.
The interesting issue isn’t whether Fodor is right—he isn’t—but why he should have taken against Darwin so. Some of his arguments suggest an answer. One of the founding principles of Fodor’s computationalist school of cognitive science is its rejection of associationist psychology. Where computationalists like Fodor hold that we are born with innate cognitive programmes, associationists maintain that our brains are shaped by experience of stimulus-reward patterns. Fifty years ago psychology, under the leadership of BF Skinner, did little but study such patterns in pigeons and rats. That is all now history. Young computationalists today are brought up on tales of how Noam Chomsky, Fodor’s longtime colleague at MIT, slew the associationist dragon once and for all with his demolition of Skinner’s theory of language in 1959.
Fodor wants to do to Darwin what Chomsky did to Skinner. At various points in their book, Fodor and Piattelli-Palmarini point out that there are strong analogies between associationist psychology and Darwinism. Both appeal to mechanisms that favour items that produce favourable effects. So it is arguable, and Fodor and Piattelli-Palmarini repeatedly argue it, that if associationist psychology is all wrong then Darwin must be all wrong too.
While this may explain what Fodor is up to, it scarcely adds to the strength of his case. Associationist psychology is no more all wrong than Darwin is. It may explain a lot less than Skinner supposed, but that doesn’t mean it explains nothing. Fodor has fought long and hard to root out any traces of associationism from psychology, but his intolerance is starting to look threadbare. The last couple of decades have seen a revival of associationist thinking, under the heading of “connectionism,” and it has proved able to explain parts of psychology that Fodor’s computationalism cannot reach. Bringing in Darwin only makes things worse. Fodor may be able to fool some of the psychologists some of the time, but he has no chance of persuading the wider biological community of claims they know to be false.
This is an unfortunate book. Fodor is a major thinker who has done much to shape thinking about the mind, and one of his strengths has always been to follow the argument where it leads. Many of his views have surprising implications, but he has often been able to show that they are sound. This time his argument has run away with him. It will persuade no one and serve only to lessen his standing.
When Jerry Fodor says that Darwin is wrong, a lot of people will sit up and take notice. Fodor isn’t some religious crank, but one of the most respected figures in the academic world: a prolific author, professor of philosophy and founding father of the discipline of cognitive science. His reputation, however, is likely to be dented by this latest book. Fodor has a successful record as a controversialist, but in taking on Darwin he has bitten off more than he can chew.
Fodor isn’t the kind of thinker you would expect to oppose Darwinism. He has devoted his life to arguing that the human mind is a finely structured machine. His work straddles philosophy and psychology. As Fodor sees it, the human mind is best viewed as an innately structured digital computer. It may not be made of silicon chips, but it works in essentially the same way, with the help of a wide range of inbuilt “programmes” and “databases.”
Readers of the London Review of Books and the Times Literary Supplement will know that Fodor has a variety of interests and an enviable prose style. What Darwin got Wrong displays his characteristic punchiness and fondness for a throwaway line. He may have a co-author in Massimo Piattelli-Palmarini, but the prose bears Fodor’s stamp throughout. Presumably Piattelli-Palmarini, a biologist turned cognitive scientist, was brought in to add biological verisimilitude. In any case, the style and the biological facts may be fine, but the argument is no good.
Fodor and Piattelli-Palmarini’s target is natural selection, not evolution. They are happy to accept that life on earth has a common ancestry. After all, as they tell us, they are both fully paid-up materialist atheists. It is Darwin’s specific theory of the mechanism responsible for evolution that they don’t like. They deny that natural selection drives evolution by favouring those organisms that are well adapted to their environments.
They have two objections to natural selection. The first is familiar. Following the lead of the late Stephen Jay Gould, they point out that any number of biological traits, from the shape of the panda’s thumb to our own troublesome appendixes, are forced on us by history rather than any adaptive shaping of organisms to environment. Natural selection can only tinker with pre-existing designs, and so is often stuck with historical hangovers. This point is relatively uncontentious. While there is room to debate its importance, even ultra-Darwinists like Daniel Dennett and Richard Dawkins devote much discussion to the fact that natural selection is often constrained by the materials it is given to work with.
Fodor and Piattelli-Palmarini’s second objection is much more peculiar. Not only does natural selection fail to explain everything—it doesn’t explain anything. It never selects traits because they help organisms to survive. This goes far beyond Stephen Jay Gould, and indeed it is hard to take seriously. If Fodor and Piattelli-Palmarini are right, polar bears don’t have white fur because it confers advantages in the Arctic; we don’t have eyes because they help us to see; and in general there is no tendency for natural selection to preserve adaptive traits.
Fodor and Piattelli-Palmarini do have an argument for these strange claims. They say that natural selection is insensitive to the difference between good traits and bad ones. One of their central examples is the evolution of the heart. Hearts pump blood, but they also make thumping sounds. As a result, any selective mechanism that favours blood pumpers will willy-nilly favour noise makers too—and, while blood pumping may help survival, thumping noises are themselves unhelpful. So, they conclude, selection favours unhelpful traits as well as good ones.
It is hard to know what to say. This isn’t a good argument because, at its centre, lies a simple confusion. It is true that when an adaptive and a nonadaptive trait are tightly yoked together, natural selection will be forced to take them both or not at all, and so in these specific cases will be “blind” to the difference. But it doesn’t follow that there is no relevant difference at all between the two traits in question. Of course there is. One trait helps survival and the other doesn’t. And in general natural selection certainly isn’t blind to this kind of contrast. Organisms with helpful traits tend to leave more offspring than those without. This means that there is a general tendency for helpful traits to spread, even if unhelpful traits like thumping sounds sometimes come along for the ride.
When Fodor gave his argument a dry run in the London Review of Books a couple of years ago, it was greeted with bewilderment. Could he really be saying that polar bears aren’t white because it hides them in the snow? And it wasn’t only the ultra-Darwinists who objected. Even the usual Darwin-bashers took pains to distance themselves from his views. It takes a lot to get Steven Rose, the editor of Alas Poor Darwin, on the same side as Daniel Dennett, but Fodor managed it.
The interesting issue isn’t whether Fodor is right—he isn’t—but why he should have taken against Darwin so. Some of his arguments suggest an answer. One of the founding principles of Fodor’s computationalist school of cognitive science is its rejection of associationist psychology. Where computationalists like Fodor hold that we are born with innate cognitive programmes, associationists maintain that our brains are shaped by experience of stimulus-reward patterns. Fifty years ago psychology, under the leadership of BF Skinner, did little but study such patterns in pigeons and rats. That is all now history. Young computationalists today are brought up on tales of how Noam Chomsky, Fodor’s longtime colleague at MIT, slew the associationist dragon once and for all with his demolition of Skinner’s theory of language in 1959.
Fodor wants to do to Darwin what Chomsky did to Skinner. At various points in their book, Fodor and Piattelli-Palmarini point out that there are strong analogies between associationist psychology and Darwinism. Both appeal to mechanisms that favour items that produce favourable effects. So it is arguable, and Fodor and Piattelli-Palmarini repeatedly argue it, that if associationist psychology is all wrong then Darwin must be all wrong too.
While this may explain what Fodor is up to, it scarcely adds to the strength of his case. Associationist psychology is no more all wrong than Darwin is. It may explain a lot less than Skinner supposed, but that doesn’t mean it explains nothing. Fodor has fought long and hard to root out any traces of associationism from psychology, but his intolerance is starting to look threadbare. The last couple of decades have seen a revival of associationist thinking, under the heading of “connectionism,” and it has proved able to explain parts of psychology that Fodor’s computationalism cannot reach. Bringing in Darwin only makes things worse. Fodor may be able to fool some of the psychologists some of the time, but he has no chance of persuading the wider biological community of claims they know to be false.
This is an unfortunate book. Fodor is a major thinker who has done much to shape thinking about the mind, and one of his strengths has always been to follow the argument where it leads. Many of his views have surprising implications, but he has often been able to show that they are sound. This time his argument has run away with him. It will persuade no one and serve only to lessen his standing.
