Abstract

In this article I offer a naturalistic defence of semantic externalism. I argue against the following: (1) arguments for externalism rest mainly on conceptual analysis; (2) the community conceptual norms relevant to individuation of propositional attitudes are quasi-analytic; (3) externalism raises serious questions about knowledge of propositional attitudes; and (4) externalism might be OK for “folk psychology” but not for cognitive science. The naturalist alternatives are as follows. (1) Community norms are not anything like a priori; sometimes they are incoherent. (2) Often propositional attitudes lack determinate content: we do not know the content of thoughts or sentences because there is no fully definite content to be known. (3) Often achieving determinate content is a major socially mediated cognitive achievement that depends on just the factors of social and environmental embedding posited as individuative by externalists, so (4) externalism explains how people can, sometimes, come to have, and to know, determinate attitude contents. (5) Reference and content, for both thought and language, are determined by complex and messy dialectical relations involving many such environmental and social factors; consequently, determinate reference, truth-conditions, etc., are somewhat uncommon outcomes. (6) The basic semantic relation is (typically imperfect) socially mediated accommodation between perceptual, cognitive, linguistic, classificatory and inferential dispositions and relevant causal structures in the environment. (7) This accommodation explains how concepts, language, taxonomies, etc., contribute to individuals' rational inductive, explanatory and practical achievements. (8) So externally individuated propositional attitudes are required for cognitive science explanations of individual human rationality and its inductive and explanatory achievements. “Individual rationality ain't (entirely) in the individual head.”