ABSTRACT
To a rst approximation, computational functionalism is the view that the mind is usefully thought of as a mechanical device, such as a computing machine. The core idea behind the mind-as-machine theory is that psychological entities should be understood in terms of what they do, rather than in terms of the stuff of which they are made. Thus computational functionalism departs from both traditional materialism and dualism, and exhibits some afnity with the behaviorist approach. The core idea of computational functionalism has been developed in various ways so that functionalism now constitutes a whole family of theories. Functionalist theories vary along several dimensions, including (a) how broadly the theories apply; (b) how they unpack the notion of a computing device or machine; and (c) whether they take the mind-machine comparison literally or metaphorically. But functionalist theories also share some core commitments, and they are generally advanced on the basis of a few common arguments. In what follows we will explore these differences and similarities. Before moving forward, two caveats are in order. First, computational functionalism should not be confused with other “functionalist” theories in psychology and philosophy of science. In particular, and despite some similarities, contemporary computational functionalism is distinct from the “Chicago” functionalism advocated by American pragmatist psychologists in the late nineteenth and early twentieth centuries.1 Henceforth I will drop the qualication “computational” and speak generically of “functionalism,” except where some confusion might arise from this terminological economy. Second, I cast my net widely when collecting together the family of functionalist theories. Some philosophers and psychologists reserve the term “functionalism” for only a subset of the variations to be discussed herein. For example, some philosophers take functionalism only to be a thesis about the narrow or internal relations among psychological states; on something like this basis, Fred Dretske (1995) denies that he is a functionalist. And Ned Block (1980) uses “Functionalism” (with a capital F) to refer to the particular version of the theory exemplied by the work
of David Lewis (1966, 1972).2 I trust that my less restricted use of the term will be vindicated if it allows us to systematize and explain a range of philosophical views. So let us now proceed to doing so.
