Wednesday, June 17, 2009

John Dupre's Darwin's Legacy

Darwin’s Legacy: What Evolution Means Today
John Dupre
Reviewed by Ben Picozzi

Darwin’s Legacy is John Dupre’s misleadingly-titled critique of contemporary trends in evolutionary science. Given its title, one might expect a broad explanation of Darwin’s theory of evolution according to natural selection and its persisting scientific and social relevance. Instead, Dupre chooses to focus on the problems which attend the functionalist understanding of evolution. While it is true that Darwin was committed to a particularly rigid functionalism, Dupre focuses on functionalism in its modern – and in his view perverse – forms. A cynic might view Dupre’s use of the Darwin label as an attempt to lend credibility to his unrelated academic crusade against a ‘reductionist’ functionalism.

Dupre focuses on two major targets: genetic-selection and evolutionary psychology. He spends the vast majority of his book responding to these two positions rather than adding anything positive to the discussion concerning Darwin’s legacy. Tellingly, the antepenultimate paragraph begins with the sentence: “So much for the negative message of this book.” While the final paragraphs are positive, such a discussion is, as might be expected, underdeveloped. This choice is unfortunate, since rather than learning about Darwin as a scientist and social figure, the reader only learns about Dupre’s hostility to functionalism. However, this focus is also what makes his book interesting, since laudatory accounts of Darwin’s legacy have become trite.

Dupre is a philosopher of science and consequently carries a philosopher’s approach in his discussions. While this perspective is often beneficial – Dupre has an excellent understanding of the philosophical positions which surrounded Darwin’s theory of natural selection – it can also detract from his argument. Dupre expects the same rigorous attention to vocabulary from his scientific adversaries that he does from his philosophical peers. As a result tends to read functionalism into their views to a greater extent than is warranted at the risk of tilting wildly at imaginary windmills. Dupre seems to believe that anything which is excluded from the scope of evolution is considered to be unimportant in determining the phenotypes of later generations. However, it is unlikely that there are any contemporary biologists who believe that genetic characteristics are the only relevant determinants. Even supporters of genetic-selection accept that there are a range of factors, including development factors, which are contributory. (Dawkins, for example, celebrated for his defense of genetic-selection is also celebrated for his exposition of cultural evolution.) In restricting evolution to genetic characteristics, what they mean is that such characteristics establish a particularly interesting sort of relationship between progenitors and their offspring. Dupre ignores this in order to present the proponents of functionalism as more narrow-minded then they actually are.

Similarly, Dupre’s treatment of evolutionary psychology seems primarily motivated by the philosophical problem of other minds. Although he does mention the scientific difficulties which attend any theory which attempts to attribute anything resembling a ‘function’ to mental states, these difficulties are rooted in the philosophical tradition which assigns a special epistemic status to the mind. Remarkably, Darwin saw this very tradition as a threat to his naturalistic theory of evolution and devoted an entire chapter of The Origin to refuting the view that the ‘instincts’, which he understands as a broad range of mental states, are somehow independent of his theory of natural selection. Obviously, Dupre does not believe in anything as superlunary as innate ideas. He does, however believe that mental states cannot be observed – and hence cannot be analyzed – in the same manner as physical states.

While the preceding discussion may seem critical, it should not discourage one from reading Darwin’s Legacy provided that one knows what to expect. If one is seeking to learn more about Darwinian evolutionary theory, then the majority of the book will be irrelevant. If, however, one is looking for an introduction to contemporary evolutionary debates, then Dupre provides excellent commentary.

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