These fifteen essays span almost thirty years – from 1970 (Epistemic Operators) to 1999 (The Mind's Awareness of Itself). They record a growing preoccupation with the mind's material constitution. I think of them as steps, sometimes very halting and uncertain steps, toward philosophical naturalism about the mind.

I began by worrying about very traditional epistemological questions. What makes a belief that something is F into knowledge that it is F? What makes an F-like experience a perception of an F? As the concept of information began to dominate my thinking about epistemology (circa 1980), I pursued naturalistic answers to these questions without pausing to ask what makes a belief a belief or an experience an experience. Knowledge was analyzed as information-caused belief. Perception was identified with (a particular kind of) information-carrying experience. In Knowledge and the Flow of Information (1981) I had argued that semantic information – what information (news, message) a signal carries – can be understood as an objective, a completely natural, commodity. It was as acceptable in a materialistic metaphysics as was the statistical construct of information employed by communications engineers. I therefore had, or so I thought, a naturalized epistemology. Knowledge and perception were merely specialized informational states in certain living organisms. I soon realized, however, that as long as I had no acceptable (i.e., naturalistic) account of belief, I had no acceptable account of knowledge. Until I could say what an experience was, I had no materialistic recipe for perception.