Abstract
Realism, defined as a justified belief in the existence of the external world, is jeopardized by ‘meaning rationalism,’ the classic theory of meaning that sees the extension of words as a function of the intensions of individual speakers, with no way to ensure that these intensions actually correspond to anything in the external world. To defend realism, Ruth Millikan ( 1984 , 1989a , b , 1993 , 2004 , 2005 ) offers a biological theory of meaning called ‘teleosemantics’ in which words, without requiring any contribution from the speaker’s intensions, are supposedly matched directly with their extensions by external norms. But even if one granted as a theoretical possibility that word meaning might possibly be stabilized through an external process, nonetheless, realists who wish to appeal to teleosemantics for a semantic proof of the external world must be capable of identifying these external norms, something that Millikan describes as highly fallible. Furthermore, because they can be aware of these norms only as these are internally represented, it would also be necessary for realists to verify that these internal representations accurately reflect the norms as they occur in the external world. But given that this is virtually the same stumbling block to realism found in meaning rationalism, it is concluded that teleosemantics is not likely to restore faith in this worldview.