Abstract

One of the greatest challenges facing materialist theories of the human mind is the problem of intentionality. As many non-materialists of various stripes have pointed out, it is very difficult to say, if the human mind is a purely material thing, how this material thing can be about or represent another thing wholly distinct from itself. However, for their part, these same non-materialists have relied heavily or exclusively on this intuition that one material thing cannot be about another. In this paper, that hole in the intentionality objection to materialist theories of mind is filled by way of providing the germ of a new theory of the metaphysics of intentionality. On this view, intentionality just is partial identity. Partial identity is a concept introduced by David Armstrong and used by Donald Baxter to give a metaphysics of instantiation. The aboutness exhibited by our mental activity is simply a partial identity relation between the mind and the object of thought. This thesis, I contend, is a faithful interpretation of Brentano’s “intentional inexistence,” which the objects of thought have in the mind and which he held to be characteristic exclusively of mental phenomena. Some interesting and fortuitous consequences, including an elucidation of precisely why one material thing can never be about something distinct from itself, are then examined, and finally a defense against some objections is given.