In my opinion, the two main topics in the philosophy of mind are content and consciousness. As the title of my first book, Content and Consciousness (1969) suggested, that is the order in which they must be addressed: first, a theory of content or intentionality--a phenomenon more fundamental than consciousness--and then, building on that foundation, a theory of consciousness. Over the years I have found myself recapitulating this basic structure twice, partly in order to respond to various philosophical objections, but more importantly, because my research on foundational issues in cognitive science led me into different aspects of the problems. The articles in the first half of Brainstorms (1978a) composed in effect a more detailed theory of content, and the articles in the second half were concerned with specific problems of consciousness. The second recapitulation has just been completed, with a separate volume devoted to each half: The Intentional Stance (1987a) is all and only about content; Consciousness Explained (1991a) presupposes the theory of content in that volume and builds an expanded theory of consciousness.
1. Beginnings and Sources
Although quite a few philosophers agree that content and consciousness are the two main issues confronting the philosophy of mind, many--perhaps most--follow tradition in favoring the opposite order: consciousness, they think, is the fundamental phenomenon, upon which all intentionality ultimately depends. This difference of perspective is fundamental, infecting the intuitions with which all theorizing must begin, and it is thus the source of some of the deepest and most persistent disagreements in the field. It is clear to me how I came by my renegade vision of the order of dependence: as a graduate student at Oxford, I developed a deep distrust of the methods I saw other philosophers employing, and decided that before I could trust any of my intuitions about the mind, I had to figure out how the brain could possibly accomplish the mind's work. I knew next to nothing about the relevant science, but I had always been fascinated with how things worked--clocks, engines, magic tricks. (In fact, had I not been raised in a dyed-in-the-wool "arts and humanities" academic family, I probably would have become an engineer, but this option would never have occurred to anyone in our family.) So I began educating myself, always with an eye to the curious question of how the mechanical responses of "stupid" neurons could be knit into a fabric of activity that actually discriminated meanings. Somehow it had to be possible, I assumed, since it was obvious to me that dualism was a last resort, to be postponed indefinitely.
(The whole paper is now available in Daniel Dennett, Brainchildren, Essays on Designing Minds, MIT Press and Penguin, 1998.)