Realism and Theoretical Unification

Abstract

Abstract Michael Friedman (1983) has presented an ingenious analysis that at once provides a new argument for scientific realism and explains why theoretical unification is a valued scientific accomplishment. His argument for realism, in broad outline, runs as follows: (F1) Theoretical unification results in better confirmed accounts of the world than we would otherwise be able to obtain (this is why unification is valued). (F2) Only scientific realists have rational grounds for unifying theories. (F3) Therefore, we should be realists. In section 4-1, I claim that this argument is defective on two counts: the argument is circular, and F2, the second premise, is false. However, subsequent sections show that F1 is true and that its truth has an interest and significance that is independent of the role it plays in the argument for realism. Friedman’s argument for F1 makes reference to a mode of theoretical reasoning that has been largely neglected by philosophers of science. Friedman maintains that this mode of reasoning accounts for the epistemic benefit reaped by a successful theoretical unification. I agree that Friedman has succeeded in capturing one reason why some instances of unification constitute scientific progress (section 4.2). However, in section 4.3 I claim that there are epistemic benefits to some types of unification that require a different account. I then show that Friedman’s account and mine are two instances of a broader category of theoretical strategies, none of which has yet received its philosophical due (section 4.4). Finally, I close with a comparison between my account of the varieties of theoretical strategies and Laudan’s (1977) seminal analysis of”conceptual problems” (section 4.5). Some aspects of this protracted meditation on F1 figure in the analyses of following chapters. In particular, the mode of reasoning used by Friedman to establish F1 reappears in a refutation by Laudan and Leplin of a famous argument for antirealism (see section 6.2). However, a lot of the material in this chapter has no immediate bearing on the realism issue. It’s here because it emerges directly from the contemplation of F1.