QUESTIONS OF LEGITIMACY: THE POSTMODERN

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1 Chapter 15 QUESTIONS OF LEGITIMACY: THE POSTMODERN CRITIQUE OF SCIENCE Yet in the choice of these man-made formulas we can not be capricious with impunity any more than we can be capricious on the common-sense practical level. We must find a theory that will work; and that means something extremely difficult; for our theory must mediate between all previous truths and certain new experiences. It must derange common sense and previous belief as little as possible, and it must lead to some sensible terminus or other that can be verified exactly. To work means both these things; and the squeeze is so tight that there is little loose play for any hypothesis. Our theories are wedged and controlled as nothing else is. Yet sometimes alternative theoretic formulas are equally compatible with all the truths we know, and then we choose between them for subjective reasons. (William James) ABATTLE is raging in academia over the issue of whether objective knowledge is possible. The opposing camps are not really very well defined, but in broad terms we might say this: the traditionalists, on one side, favor western culture, values that are absolute, and truth; the postmodernists, on the other side, favor multiculturalism, relativism, and a worldview in which truth doesn t exist. While these caricatures oversimplify the interesting range of issues involved, the ramifications for fields like history, philosophy, and sociology are clear. The sciences have also been drawn into this conflict. Scientists have generally thought of their discipline as objective, free of values, and leading to definite knowledge (as opposed to mere opinion). But the postmodern critique denies the possibility of objectivity and of definite knowledge. Postmodernists point out that science is a product of western culture; if we deny the primacy of western culture, then science is just another claimant (among many) for the validity of its results. An entire area of academia (science studies) has been built up around this basic idea. A number of scientists have been rather vocal in taking exception to these postmodern claims. A point these scientists often press is that many of the postmodern critics

2 208 CHAPTER 15 of science have little understanding of either the results or the methods of science; for this reason, such critics are poorly qualified to make the claims they do. This attitude came to a head in 1996, when physicist Alan Sokal wrote a parody imitating typical postmodern papers and then published it in one of their leading journals. Leaving aside questions of whether this action was ethical and what (if anything) we might conclude from the episode, it certainly brought the controversy to everyone s attention. Several murky issues are tangled together in this controversy. Is science merely the tool of an iniquitous imperialistic system? If so, is this situation necessary, or is it contingent? Does the validity of a scientific result depend for its warrant on the justice of the sociopolitical system in which the science is done? Is the achievement of scientific consensus a rational process, or a political process? Are scientific theories accurate reflections of a pre-existing reality, or merely social constructions based on negotiations between interest groups? Are the knowledge claims of science more valid than knowledge produced by other ways of knowing, or are all such claims equally valid? Let s explore these questions and try to untangle some of the relevant issues. One source of confusion stems from mixing together two very different issues: the question of whether science is good or bad, and the question of whether science delivers a correct understanding of nature. The validity of an idea doesn t depend on its moral virtue (or lack thereof). The question of whether science is good must surely depend on what our values are, and that discussion belongs in a different place (chapter 11, which includes a serious consideration of these matters). The second question (is science valid?) is our primary interest here. 1. THE CONSTRUCTION OF SCIENCE Is the Definition of Scientific Validity a Cultural Artifact? One of the most abstract, general, and powerful arguments of the science critics is based on the following premise: We and our thinking processes are products of our culture. Even our most fundamental assumptions are culture-bound, rather than being true in any absolute sense. For example, two of the fundamental assumptions of science are that, in formulating our understanding of nature, observational evidence is paramount and logical coherence is necessary. A cultural critic might argue that these assumptions are really just products of European thought during the last four centuries and need not be universally made. This argument is extremely difficult to counter because any point you make can be dismissed. Contrary evidence is not decisive if the primacy of evidence can be denied. Logical flaws can likewise be ignored if logic itself is merely a cultural artifact. Scientists often point to the success of science in making predic-

3 QUESTIONS OF LEGITIMACY 209 tions, but the high esteem we bestow on predictive success is, once again, a product of culture. Along these lines, the philosopher Paul Feyerabend has made the comment that voodoo is no better or worse than science as a way of understanding the world. If we don t get to make any presuppositions at all, who is to say that Feyerabend is wrong? But this argument has force only if we restrict our attention to the most extreme alternatives. I am willing to concede that science has no absolute superiority to other thought systems in the sense I ve just outlined. Science is indeed the product of a particular culture in a specific set of historical circumstances. However, the alternative to science is absolutely superior does not have to be all modes of thinking are equally valid. Between these two extremes lies a continuum on which we can make and justify judgments. That science is intrinsically superior to any other realm of human endeavor is certainly questionable, but that science is a purely arbitrary construct is at least equally questionable. Are the Results of Science Social Constructions? Inspired by the work of Thomas Kuhn (chapter 14), sociologists of science began to look more closely at the process by which scientists arrive at a consensus. They reported that the process is not the purely rational sifting of evidence that we sometimes pretend it is. In fact, scientists are humans, and the workings of the scientific community are a process of social negotiation. Matters of prestige, friendship, and power (which should be irrelevant) do enter into these social negotiations. The question is this: Do these social forces warp, or even determine, the results of science? In the early stages of a scientific discussion, when the ideas are still unclear and the evidence is sparse, these illegitimate social factors must surely influence the discussion. The postmodern critics who subscribe to the so-called strong program of social constructivism argue that these influences always permeate the discussion and eventually determine the outcome. Many scientists (and like-minded philosophers) maintain that such social influence is limited by the constraints imposed by nature; there is a reality, and it will decide the issues in the end, regardless of prestige and power. An example illustrates this point. When S. Chandrasekhar was a young and unknown scientist, he performed a set of calculations suggesting that massive stars end their lives by gravitational collapse (black holes, as we now call them). The foremost authority in astrophysics at that time, Sir Arthur Eddington, could not accept such an absurd-sounding conclusion. He thought that something (unspecified) must be wrong with the theory, and he said so. Although Chandrasekhar had the better argument, Eddington s conclusion was almost universally accepted in the scientific community. No observational evidence of any sort existed then, the idea was

4 210 CHAPTER 15 strange as well as new, and Eddington s prestige was enormous. But today we accept the presence of black holes in the universe with few reservations. This change is due to the many new measurements made in astronomy (see chapter 3), working together with an increasingly sophisticated theoretical understanding of the issues. But this process of changing from a world without black holes into a world with black holes took roughly two generations to complete. Although nature might eventually decide the issues in the end, social prestige can still impose a wrong-headed conclusion for quite a while. Suppose the issues are extremely subtle and complex; the observations and measurements needed to resolve the issues are difficult to acquire; and there is no substantial theoretical context within which to work. If all of these statements are true, then a situation in which social factors prevail over nature s voice might last for some time. The postmodern critics can be right for a given historical period, even if nature does ultimately constrain our constructions in some profound manner. 2. UNDERDETERMINATION AND IDEOLOGY The Quine-Duhem Thesis Revisited There is a variation of the constructivist argument, based on the Quine- Duhem thesis (see chapter 14), that would tend to blunt the point I just made. The basic idea of the Quine-Duhem thesis is that scientific theories are not uniquely determined by observations and experiments. A given set of results can be interpreted in a number of different ways. If the data aren t deciding the content of our theories, then we must (at least in part) be freely constructing them. Put differently: We don t discover scientific results, we invent those results. Since science is done by people working together in the scientific community, inventing results is a social process. While there is surely a certain amount of truth in this outlook, careless application of the idea leads to an extremely distorted vision of science. The stories of discovery related in Part I, taken collectively, reveal a much richer tapestry than the threadbare statement that science is a social construction. Science is a construction, but by no means is it an arbitrary construction. Our data may not uniquely determine our theories, but our data working together with our demand for logical coherence effectively whittles down the possibilities quite dramatically. Two major problems plague the postmodernist use of the underdetermination argument. One problem is the blithe assumption that it s easy to come up with any number of alternative theories that explain a myriad of empirical observations. In fact, as anyone who has made the attempt

5 QUESTIONS OF LEGITIMACY 211 will tell you, it s usually difficult to come up with even one satisfactory explanation. Since all of our explanations must interlock coherently, the Quine-Duhem thesis fades in relevance. The second problem goes deeper in its implications. A really good scientific theory gives us back much more than we put into it. A theory devised to solve one problem turns out to have the power to solve hundreds of unanticipated problems. An explanation for what is now known might also explain new discoveries made decades from now, discoveries that no one could ever have foreseen. This unexpected power of theories to advance far beyond the boundaries within which they were invented is difficult to understand if such theories are merely arbitrary constructions. To me, this suggests that these theories are in some sense a mirror of reality. The claim here isn t that science gives us a complete and undistorted grasp of reality; or that science allows us to apprehend all possible levels of reality; or that science is the only valid approach to reality. However, scientific results are not arbitrary; we achieve an understanding of nature that is meaningful and genuine in the course of scientific investigation. Theories, Metaphors, and Cultural Myths We need to be very careful about the interpretations we draw from scientific results. The postmodern commentators on science make some valid criticisms, but I think these criticisms are often misdirected toward science itself rather than questionable interpretations that pretend to be science. For example, a scientist might proclaim that humanity has been dethroned from a central place in the cosmos. A scientist might make this statement, but it s not science. Such a statement is a metaphorical extension of the actual scientific facts and is highly charged with emotional overtones and value implications. Many cultural critics have castigated science for being soulless, mechanistic, atheist, capitalist, or what have you. Both scientists and critics of science have unfortunately sometimes confused scientific results with the value-laden interpretations that they overlay on these results. (A more extended discussion of this issue is found in chapter 11.) The problems involved in disentangling metaphors from theories can be subtle because the metaphors are often crucial in the process of constructing the theories. In addition, these metaphors become entrenched in the interpretations of what a theory means, especially in the larger culture. A clear example is evolutionary theory, which has a well-defined role in science (providing a coherent explanation of a set of observations), a broader role in both science and culture (providing, in Darwin s words, a view of life ), and finally an extremely broad role in culture as a contemporary creation myth. All of these roles might be

6 212 CHAPTER 15 legitimate on some grounds, but only the first is legitimate as science. Making these distinctions isn t easy in practice, however, because the different roles all operate simultaneously under the same name (evolution by natural selection). Back to Politics A major claim of the postmodern program is that the results of science merely reflect the political ideologies, economic interests, and cultural prejudices of scientists (and/or the elites who employ the scientists). I have argued that this statement, taken literally as a kind of universal assertion, is wrong. But if we back away from this extreme position and ask ourselves where a less rigid version might apply, we find a more fertile area for discourse. A number of postmodern scholars have done this sort of worthwhile analysis, and it s unfortunate that more extremist claims have dominated the discussion. For example, political and economic considerations have clearly played a large role in shaping the scientific research agenda (military, agricultural, and medical research are all examples). These extrascientific influences don t completely shape the research agenda, since the science itself drives research into unexpected directions, but their influence is undeniable. Similarly, there are real questions concerning gender discrimination in the sciences (even if the claim that science is a manifestation of male thinking is nonsense). Finally, let s reconsider the situation where underdetermination is most important (complex phenomena, sparse data, and no fundamental theory). If deeply held values are also involved, then hidden ideological presuppositions might well dominate the discussion. As an example, consider the long-running debate over the question of environmental influences versus inherited traits in determining intelligence. The quotation marks are there because it s not clear that causal determination is even the proper way to frame the issue and ask questions. Nor is it clear that intelligence is a single well-defined concept, much less an independent object of study. Vast social and economic resources might be redirected based on the outcome of this debate. The questions involved touch on deep underlying visions of what it means to be human. Given all of these circumstances, proponents of a particular (and definitive) position on this issue (the nature/nurture debate over intelligence) aren t basing their position on purely scientific grounds. If the postmodern critique draws attention to the murky foundation of issues like this, then I think the postmodernists have performed a valuable service. Perhaps the outcome of such a critique can isolate the genuinely scientific portions of the debate and the valid conclusions that can be drawn.

7 QUESTIONS OF LEGITIMACY 213 FOR FURTHER READING Revolutions and Reconstructions in the Philosophy of Science, by Mary Hesse, Indiana University Press, Construction and Constraint, edited by Ernan McMullin, University of Notre Dame Press, Reconstructing Scientific Revolutions, by Paul Hoyningen-Huene, University of Chicago Press, The Flight from Science and Reason, edited by P. R. Gross, N. Levitt, and M. W. Lewis, New York Academy of Sciences, Introduction to the Philosophy of Science, by Robert Klee, Oxford University Press, EPIGRAPH REFERENCE: William James, Pragmatism, The New American Library, 1974 (original edition 1907), p. 142.