   A significant number of physicalist philosophers subscribe to the task of reconciling the existence of intentionality with a physicalist ontology (for a forceful exposition see Field 1978, 78–79). On the assumption that intentionality is central to the mental, the task is to show, in Dennett’s (1969, 21) terms, that there is not an “unbridgeable gulf between the mental and the physical” or that one can subscribe to both physicalism and intentional realism. Because intentional states are of or about things other than themselves, for a state to have intentionality is for it to have semantic properties. As Jerry Fodor (1984) put it, the naturalistic worry of intentional realists who are physicalists is that “the semantic proves permanently recalcitrant to integration to the natural order”. Given that on a physicalist ontology, intentionality or semantic properties cannot be “fundamental features of the world,” the task is to show “how an entirely physical system could nevertheless exhibit intentional states” (Fodor, 1987). As Dretske (1981) puts it, the task is to show how to “bake a mental cake using only physical yeast and flour”. Notice that Brentano’s own view that ‘no physical phenomenon manifests’ intentionality is simply unacceptable to a physicalist. If physicalism is true, then some physical things are also mental things. The question for a physicalist is: does any non-mental thing manifest intentionality?