Published online by Cambridge University Press: 07 April 2017
What is it reasonable to believe about our most successful scientific theories such as the general theory of relativity or quantum mechanics? That they are true, or at any rate approximately true? Or only that they successfully ‘save the phenomena’, by being ‘empirically adequate’? In earlier work I explored the attractions of a view called Structural Scientific Realism (hereafter: SSR). This holds that it is reasonable to believe that our successful theories are (approximately) structurally correct (and also that this is the strongest epistemic claim about them that it is reasonable to make). In the first part of this paper I shall explain in some detail what this thesis means and outline the reasons why it seems attractive. The second section outlines a number of criticisms that have none the less been brought against SSR in the recent (and as we shall see, in some cases, not so recent) literature; and the third and final section argues that, despite the fact that these criticisms might seem initially deeply troubling (or worse), the position remains viable.
2 For the real story see my ‘Fresnel, Poisson and the White Spot: The Role of Successful Prediction in the Acceptance of Scientific Theories’ in Gooding, G. et al. (eds.) The Uses of Experiment (Cambridge: Cambridge University Press, 1989)Google Scholar—but the facts about the history do not affect the issues tackled here.
3 The situation is, in fact, not so clear once it is accepted that we can (at best) claim only ‘approximate’ truth for even our best theories: clearly an approximately true theory is strictly speaking false and hence will have infinitely many false consequences. Here I shall avoid these complications and simply assume that if a theory is approximately true in the appropriate sense then it is no miracle that it gets some prediction correct to within observational accuracy.
4 Worrall, J., Reason in ‘Revolution: A Study of Theory-Change in Science (Oxford: Oxford University Press, 2007).Google Scholar
5 As is well-known, Maxwell himself continued throughout his life to hold that the field must in the end be the product of an underlying material medium. However, in what might be called the mature version of Maxwell's theory, the field is indeed sui generis.
6 Laudan, L., “A Confutation of Convergent Realism” repr. in The Philosophy of Science, Papineau, D. (ed.) (Oxford: Oxford University Press, 1996), 107–138.Google ScholarPubMed Of course what the claim that we now ‘know’ those earlier theories to be false means is that our current theories (which are objectively better supported than their predecessors) imply that they are false. (Just how ‘radically’ false they imply them to be will be an issue that looms large in what follows.)
7 Of course everyone believes that our theories are improving—in the sense at least that later theories are better empirically supported than their predecessors (the so-called phenomenon of ‘Kuhn loss’ of empirical content being a myth). But this is clearly a question of degree, while in order to justify rejecting the conclusion of the ‘pessimistic induction’ we would surely need some reason to think that there was a difference in kind between earlier theories and the present ones. As it stands, rejecting the idea that our current theories are likely to be replaced because earlier ones have on the grounds that our current theories are better supported than the earlier ones (see e.g. Lipton, Peter, ‘Tracking Track Records’, Proceedings of the Aristotelian Society, Supplementary Volume LXXIV (2000), 179–205)CrossRefGoogle Scholar would be rather like justifying rejecting the idea that it is likely that the current 100m sprint record will eventually be broken by pointing to the fact that the current record is better than the earlier ones.
10 Op. cit. note 9, 160.
11 Op. cit. note 9, 161.
12 Op. cit. note 1.
14 Op. cit. note 1, 160.
15 Op. cit. note 13, chapter 3.
16 For more details and references see op. cit. note 13, 40–44.
17 In fact we would surely want something stronger than this probabilistic condition if we are fully to capture the explanation claim—not just that e is entailed by T but that T (and perhaps the ‘way’ in which it entails e) have some further ‘nice’ properties. See below 144–147.
21 Zahar, E.Poincare's Philosophy: From Conventionalism to Phenomenology, (Chicago: Open Court, 2001).Google Scholar
22 Larry Laudan complains (op. cit, note 6) that the notion of ‘maturity’ is introduced by realists as an ad hoc device: whenever it seems like there is no sense in which an earlier theory continues to look ‘approximately true’ in the light of its successor, the realist can claim that that earlier theory was accepted only when the science that it contributes to was ‘immature’. However, as I have explained before (op cit. note 1), it seems that the realist should be ready to ‘read off’ her notion of maturity from the NMA which is her main support—taking it that a scientific field attains maturity once its accepted theory enjoys genuine predictive success (that is, it predicts some general phenomenon that was either unknown at the time or was not used in the development of the theory concerned).
23 See, e.g., his ‘The Unseen World’ in Cheyne, C. and Worrall, J. (eds.) Rationality and Reality: Conversations with Alan Musgrave, (Springer, 2007).Google Scholar
24 Op. cit. note 9, 149–150.
26 Of course if you presuppose set theory then the theoretical predicates can be replaced by predicates varying over sets and then the Ramsey sentence is entirely first-order.
27 See, for example, Suppes, P., Introduction to Logic, (New York: Van Nostrand, 1957).Google Scholar
29 Op. cit. note 20, 627–628.
30 This section of the paper follows the treatment in Worrall, J. and Zahar, E., ‘Appendix IV: Ramseyfication and Structural Realism’ in Zahar, E.Poincare's Philosophy: From Conventionalism to Phenomenology, (Chicago: Open Court, 2001), 236–251.Google Scholar I am in general greatly indebted to Elie Zahar for many long discussions of structural realism and for invaluable help with some technical issues.
31 Op. cit. note 19, 144.
32 Op. cit. note 20, 635, emphasis added.
33 Op. cit. note 30, 235.
34 Putnam, H., ‘What is Mathematical Truth’ in Mathematics, Matter and Method (Cambridge: Cambridge University Press, 1975), 69–70.Google Scholar
35 Op. cit. note 21, 86.
36 My account in this section of the paper is particularly indebted to a number of conversations with Elie Zahar.