Mind: A Brief Introduction (John R. Searle) / quote 53 of 138
Identities discovered, not defined
The model for the behaviorists was one of definitional identities. Pains are dispositions to behavior in a way that triangles are three-sided plane figures. In each case it is a matter of definition. The identity theorists said no, the model is not definitions, but rather empirical discoveries of identities in science. We have discovered, as a matter of fact, that a bolt of lightning is identical with an electrical discharge; we have discovered, as a matter of fact, that water is identical with H2O, and we are now discovering, and the discovery is proceeding daily, that mental states are really identical with brain states.