a1 University of Western Ontario
Pollock's How to Build a Person is a highly sophisticated defence of the “strong” Artificial Intelligence (AI) program within the framework of a physicalist/functionalist ontology. Its central thesis is as robust as any defender of strong AI could possibly want it to be: to build a person—“a thing that literally thinks, feels, and is conscious” (p. ix)—is to build a physical system that adequately models human rationality; and building such a system is, essentially, a computational task. The epistemological groundwork for the computational task (a task already underway at the University of Arizona under the name “the OSCAR project”) is sketched in the sixth and last chapter of the book—a 64-page-long chapter (“Cognitive Carpentry”) where Pollock presents the main lines of a general theory of rationality which he has been developing over the course of many years. The bulk of the book (chaps. 1 to 4) is devoted to an articulation and defence of what Pollock takes to be the metaphysical underpinnings of his conception of a person as an intelligent machine: token-physicalism, agent materialism, psychophysical supervenience and (a form of) analytical functionalism. This part of the book, which will be the focus of this review, provides an account of “the physical basis for mentality”—an account of what it is that makes a physical structure capable of having mental states relevantly like our own. And since on the proposed account mental capacity “involves a way of codifying information—a system of mental representations” (p. 93), Pollock devotes a chapter (chap. 5) to the semantics of “the language of thought”; though basically a digression, since “semantics plays no role” in the computations involved in rational thought, the chapter is intrinsically very interesting, bearing as it does on current debates on thought ascription and content individuation.