Proceedings of the XXII World Congress of Philosophy

Volume 39, 2008

Philosophy of Language

Psychological Essentialism and Semantic Externalism Evidence for Externalism in Lay Speakers’ Language Use

Some experimental studies have recently claimed to undermine semantic externalism about natural kind terms. However, it is unclear how philosophical accounts of reference can be experimentally tested. We present two externalistic adaptations of psychological placeholder essentialism, a strict externalist and a hybrid externalist view, which are experimentally testable. We examine Braisby’s et al. (1996) study which claims to undermine externalism, and argue that the study fails in its aims. We conducted two experiments, the results of which undermine internalism and the hybrid theory, and support strict externalism. Our conclusion is that lay speakers’ natural kind concepts involve a belief in an external category essence, which determines reference.