Abstract

What do Jerry Fodor and Bas van Fraassen, the archetypical scientific realist and his antirealist shadow, have in common? They’re both defenders of the theory-observation distinction. It isn’t surprising that a realist and an antirealist should agree about something; but it is curious that van Fraassen’s and Fodor’s defenses of the theory-observation distinction play diametrically opposite roles in their philosophical agendas. Van Fraassen needs it to support his antirealism; Fodor wants it in support of his realism. Van Fraassen needs the distinction in order to protect antirealism from the charge of incoherence. Antirealists wish to ascribe a more exalted status to the observational import of a theory than to its nonobservational claims. Van Fraassen’s version of the antirealist thesis is that belief in observational claims is rationally warranted under some logically and nomologically possible conditions, whereas belief in theoretical claims is never warranted. This identifies the species of antirealism at issue as epistemic antirealism. This position would be a nonstarter if the observational import couldn’t be distinguished from the rest. And, in fact, denying the coherence of the theory-observation distinction has been a popular realist gambit in the debate about scientific realism.