How the mind works By Steven Pinker (review)

Abstract

136LANGUAGE, VOLUME 75, NUMBER 1 (1999) How the mind works. By Steven Pinker. New York: W. W. Norton & Company, 1997. Pp. xii, 660. Reviewed by D. Terence Langendoen, University ofArizona Pinker begins by acknowledging that 'we don't understand how the mind works'. However, we've made progress. Certain theories from a variety of disciplines now offer 'a special insight into our thoughts and feelings', which can be integrated using 'the computational theory of mind and the theory of the natural selection of replicators' (ix). The book consists of eight chapters, notes, references, and an index, all substantial. Ch. 1 (3-58) presents the book's central thesis 'that the mind is a system of organs of computation designed by natural selection to solve the problems faced by our evolutionary ancestors in their foraging way of life' (x). Ch. 2 (59-148) discusses the computational theory of mind, including refutations of the views oftwo of its major critics, John Searle and Roger Penrose, and a very readable account of connectionism. In Ch. 3 (149-210), P discusses the theory of natural selection and argues that four conditions were necessary for the emergence of intelligence in our ancestors: a well-developed (stereoscopic, color) visual system, group living, the hand, and hunting. Anticipating Alfred Rüssel Wallace's objection that natural selection cannot account for human intelligence, P writes: 'Many theorists have wondered what illiterate foragers do with their capacity for abstract intelligence. The foragers would have better grounds for asking the question about modern couch potatoes' (188). Chs. 4-7 are devoted to visual perception (21 1-98), reasoning (299-362), emotion (363-424), and social relations (425-520); Ch. 8 (525-65) discusses art, music, literature, humor, religion, and philosophy. Although no chapter discusses language per se (the reader is referred to Pinker 1994), two linguistic topics are central to P's concerns in this book: metaphor and logical form. Metaphor is an important part of P's solution to Wallace's puzzle about why our ancestors should have evolved an intelligence equivalent to our own. Following John Tooby and Leda Cosmides's theory of 'ecological rationality' (304), P maintains that the human mind is not adapted to think about arbitrary entities and their relations; instead its intelligence is subjectspecific : 'It is equipped with faculties to master the local environment and outwit its denizens. People . . . have several ways of knowing . . . adapted to the major kinds of entities in human experience: objects, animate things, natural kinds, artifacts, minds, and . . . social bonds and forces' (352). Metaphor extends our mental ability to cope with other kinds of things and relations, and P suggests that it is a process like evolutionary change 'which often works by copying body parts and tinkering with the copy. ... A similar process may have given us our language of thought. Suppose ancestral circuits for reasoning about space and force were copied, the copy's connections to the eyes and muscles were severed, and references to the physical world were bleached out. The circuits could serve as a scaffolding whose slots are filled with symbols for more abstract concerns like states, possessions, ideas, and desires' (355). But surely this is not a theory of metaphor; at best it is a metaphor of metaphor. To be a theory, it would require at minimum a specification of what is being replicated and how, and of how natural selection comes into play. The nature of the logical form of ordinary sentences of natural languages figures prominently in P's refutation of the associationist theory of meaning, particularly as it is embodied in the version of connectionism he calls 'connectoplasm'. P points out that the difference between the two interpretations of the sentence Everyforty-five seconds someone in the United States sustains a head injury (both of which figure in the joke whose punch line is Omigod! That poor guy!) depends on the relative scope of the existential quantifier binding the subject variable and the phrase every forty-five seconds, and observes: Our mentalese must have machinery that does something similar. But so far, we have no hint as to how this can be done in an associative network' (123). However, P later retracts...