Elliott Sober. Philosophy of Biology, Oxford University Press (1993) 231 + xix pp.
Philosophy of Science., 63, 1996, 143-145.
Elliott Sober is among the leading contemporary contributors to the philosophy of biology. He also has an exceptional ability to explain difficult ideas clearly. He is therefore very well equipped to provide an accessible yet state-of-the-art introduction to the philosophy of biology, and in most respects this optimistic prognosis is justified by the present volume. Focussing on evolutionary biology, Sober provides a general overview of evolutionary theory; a chapter on creationism that serves as a vehicle for the discussion of the evidence for evolution; and chapters on fitness, the units of selection, adaptationism, systematics, and sociobiology. Sober displays a thorough mastery of both the biological issues and the recent philosophical controversies that have surrounded them, and the presentation is always lucid and free from unnecessary technicalities. Anyone not thoroughly conversant with contemporary discussions of evolutionary theory could learn from this book.
There are, of course, points with which one could quibble. In the first chapter Sober is too comfortable for my taste with the idea that science is concerned to find universal laws, and with the idea that this goal can readily be transferred to a model-building conception of science. Perhaps more surprisingly though relatedly, he sees no difficulty with the possibility of laws of nature being, in some cases, mathematical derivations from idealized assumptions (pp. 17, 73). The claim that any proposition that is testable is thereby scientific (Sober's example is "the Earth is flat") (pp. 28, 46) struck me as at the least a perversion of the standard meaning of "scientific". And the discussion of Hume on the argument from design (pp.33-36) seemed to me quite unfair. Hume, as I read him, is not primarily concerned to deny the inference to a designer (indeed he appears to endorse this at the end of the Dialogues) but rather to deny that anything about the nature of the designer can be inferred from empirical evidence. Thus he provides overwhelming arguments that no conclusions about the moral properties of the deity can be derived from natural theology even if a cause of order in the universe which "probably bear[s] some remote analogy to human intelligence" should be acknowledged. Sober, it seems to me, in criticizing Hume's argument against the inference to an intelligent designer, attacks an argument that is at most tangential to Hume's main goals.
But rather than spend more time on these fairly detailed differences of opinion, I would like to raise two more general issues. I have said that this textbook provides a state-of-the-art introduction to the philosophy of biology. These more general concerns, therefore, should be seen as concerns about the state of the art.
First, Sober's book is in one respect surprisingly old-fashioned. It reflects to a striking degree the ability of a main stream of philosophy of science simply to ignore the very large body of scholarship, mainly in the history and sociology of science but also at the fringes of philosophy of science, that has been concerned to situate science in the real social world. Sober's view of science appears to be as innocent of social or political contamination as was Carnap's or Hempel's (though I take it that a good deal of classical positivism, unlike Sober, had some quite explicit political motivation.) The question whether the content of science might be affected by the political agenda of its exponents is raised briefly in Sober's discussion of sociobiology where he concludes that "it is a possibility deserving of scientific scrutiny that some scientific ideas persist for reasons other than their evidential warrant. One should not accept this suggestion glibly, but neither should it be dismissed out of hand." (p.197.) To the many scholars concerned with historical and sociological (unscientific?) investigation of the diverse causes of the persistence of scientific ideas this remark must surely be breath-taking. Certainly it belies the sometimes heralded rapprochement of history and philosophy of science.
This blindspot has striking consequences at places in Sober's book. In introducing creationist criticisms of evolutionary theory he writes: "Creationists press these questions because they have a political agenda. They wish to reduce ... the teaching of evolution and to have the biblical story of creation taught in the public schools." (P.28.) This passage clearly implies that it is not, by contrast, part of the political agenda of biologists to resist this, and have evolution taught in public schools. It only seems possible to make sense of this contrast if science is elevated to some transcendent realm above the political fray, the latter providing the home for dubious evidence and bad arguments. Perhaps more disturbingly, Sober offers an extended discussion of sociobiological theories about rape--roughly speaking, that rape is a reproductive strategy--with no reference at all to any of the feminist biologists or philosophers who have discussed the social and political implications and presuppositions of this kind of theorizing. (He does note the idea that rape should be seen as an act of violence not sex, but comments only that such a psychological claim has no bearing either way on the evolutionary claim.) Sober's final judgment on whether it is appropriate to apply the term "rape" equally to humans and ducks is that "the real problem is homology and functionally similar homoplasy, on the one hand, versus functionally dissimilar homoplasy, on the other." (P.202.) If one assumes that the issues here are purely matters of biological fact, this is no doubt a good summary of the problem. But most feminists concerned with the issue would deny that the problem with such theories is solely, or even primarily, biological, and so would deny that this was even close to the real problem. For that matter, the reader of Sober's book would have no way of knowing that there were any feminist biologists or philosophers of biology. At some point in an introductory text it does seem to me important that the student should see that science is not solely and unproblematically a source of empirical knowledge, but is also a social institution as liable to human failings as any other. This is a desideratum that Sober's book fails to meet.
The preceding point is to some extent an inevitable consequence of my second general concern about the state of philosophy of biology that Sober's book reflects. I suppose that any thriving discipline will have its conception of how it differentiates itself from its more or less benighted forebears, and this is not hard to locate in contemporary philosophy of science. It is the idea, recited with mantra-like insistence, that serious contemporary philosophy of science demands serious engagement with the details of at least some science. (The mantra-like quality of this pronouncement is finely displayed in a recent volume in which contemporary philosophers of biology reflect on their craft (Werner Callebaut, Taking the Naturalistic Turn, University of Chicago Press, 1993.)) Of course this conception is not exactly unprecedented; indeed it is perfectly captured by Locke's proposal that philosophy should be an underlabourer for the sciences. But it is perhaps as religiously enunciated now as it has ever been, and it is at its strongest in--and no doubt is in part responsible for the current prestige of--those subfields of philosophy of science devoted to a particular science (philosophy of physics, biology, etc.). Sober's book perfectly exemplifies this tendency. A rough survey of the bibliography suggests that reference to biological works outnumber philosophical ones by a ratio of about 2:1, and acknowledging that this is a somewhat arbitrary judgment, I think that this approximately represents the ratio of exposition of biological ideas to distinctively philosophical discussion in Sober's text.
Whereas it would be foolish to deny that philosophy of science has derived great benefits from this insistence on looking at the scientific details, taken to excess this insistence can have costs. First, as I implied above, the tendency for philosophy of biology to converge on theoretical biology inevitably discourages the attention to social context the absence of which in Sober's book I have just discussed. Cynics, indeed, might suspect that the highest ambition of contemporary philosophers of science is to be taken seriously by the scientists whose work they study--something hardly to be achieved by attention to the social context of science. I also kept wondering, as I read this book, who the intended audience was. My conclusion--which perhaps accords with the cynical view just mentioned--was that it would be ideally suited to a smart and moderately adventurous biology student. Such a student would be helped to get beyond the often dogmatic presentation of scientific material and see the difficult and sometimes contentious conceptual issues lying beneath the surface of scientific doctrine, but would not be encouraged to ask the kinds of deeper philosophical questions that might genuinely problematize the discipline of biology (and which would surely not be looked kindly upon by such a student's scientific mentors).
On the other hand, I suspect that most more traditionally humanistic philosophy students would find the approach if not offputting, at least uninviting. This seems a pity. Biology is, after all, surely one major source of insight into perhaps the most fundamental of philosophical questions, what it is to be human. And how far biology can go in answering that question should provide deep insight into the scope and limits of science. Perhaps this is mere nostalgic hankering after a lost unity of knowledge, but an introduction to the philosophy of biology that deeply engages the fundamental philosophical importance of the subject matter of biology while at the same time recognizing the necessity of a sophisticated grasp of the content of the science--an introduction, one might call it, to the philosophy of life--remains something to which I think we should still aspire.
In summary, Sober has provided as good an introduction to contemporary analytic philosophy of biology as one could reasonably ask for. The questions it introduces are interesting and important, and Sober's discussions of them are of a high quality. But the book also embraces and contributes to the tendencies which will keep the philosophy of biology a technical area at the margins of philosophy. It is thus an introduction that displays the limitations of its discipline as clearly as it displays its strengths.