Thomas S. Kuhn's classic book is now available with a new index.

I propose to consider the question, "Can machines think?" This should begin with definitions of the meaning of the terms "machine" and "think." The definitions might be framed so as to reflect so far as possible the normal use of the words, but this attitude is dangerous, If the meaning of the words "machine" and "think" are to be found by examining how they are commonly used it is difficult to escape the conclusion that the meaning and the answer to (...) the question, "Can machines think?" is to be sought in a statistical survey such as a Gallup poll. But this is absurd. Instead of attempting such a definition I shall replace the question by another, which is closely related to it and is expressed in relatively unambiguous words. The new form of the problem can be described in terms of a game which we call the 'imitation game." It is played with three people, a man (A), a woman (B), and an interrogator (C) who may be of either sex. The interrogator stays in a room apart front the other two. The object of the game for the interrogator is to determine which of the other two is the man and which is the woman. He knows them by labels X and Y, and at the end of the game he says either "X is A and Y is B" or "X is B and Y is A." The interrogator is allowed to put questions to A and B. We now ask the question, "What will happen when a machine takes the part of A in this game?" Will the interrogator decide wrongly as often when the game is played like this as he does when the game is played between a man and a woman? These questions replace our original, "Can machines think?". (shrink)

This is a new release of the original 1949 edition.

Intentionality is characteristic of many psychological phenomena. It is commonly held by philosophers that intentionality cannot be ascribed to purely physical systems. This view does not merely deny that psychological language can be reduced to physiological language. It also claims that the appropriateness of some psychological explanation excludes the possibility of any underlying physiological or causal account adequate to explain intentional behavior. This is a thesis which I do not accept. I shall argue that physical systems of a specific sort (...) will show the characteristic features of intentionality. Psychological subjects are, under an alternative description, purely physical systems of a certain sort. The intentional description and the physical description are logically distinct, and are not intertranslatable. Nevertheless, the features of intentionality may be explained by a purely causal account, in the sense that they may be shown to be totally dependent upon physical processes. (shrink)

This collection of 17 essays by the author offers a comprehensive theory of mind, encompassing traditional issues of consciousness and free will.

Gödei's Theorem seems to me to prove that Mechanism is false, that is, that minds cannot be explained as machines. So also has it seemed to many other people: almost every mathematical logician I have put the matter to has confessed to similar thoughts, but has felt reluctant to commit himself definitely until he could see the whole argument set out, with all objections fully stated and properly met. This I attempt to do.

This dissertation is concerned with issues which have been discussed as distinct philosophical problems and attempts to demonstrate that they have a deep underlying commonality. The disparate philosophical problems include that of action, the alleged implications of Goedel's Theorem for the mind, and Descartes's 'Cogito' argument. The various independent problems are discussed in detail, however, the dissertation also attempts to show that the independently argued positions can be seen to converge with the others, specifically implicating the notions of self and (...) self-reference. ;In the first chapter on actions, I try to sketch the outlines of naturalized account of actions and suggest that the philosophy of action has been left behind in the cognitive revolution which has come to dominate philosophy of mind generally. In particular, using the vehicle of Danto's notion of basic action, I argue that the traditional concern with causality is misplaced and arises from certain inherent perplexities concerning one's own movements. ;In the second chapter I attempt to give an analysis of Lucas's notorious argument against mechanism from the supposed implications of Goedel's Theorem. I suggest that among the fatal flaws in Lucas's argument is the failure to take into account the self-referential or 'diagonal' character of Goedel's proof. ;The third and fourth chapters consider the debates surrounding Descartes's Cogito argument. I offer a novel analysis which is nevertheless textually faithful and, indeed, permits a charitable construal of Descartes which is in contrast to the usual accounts. Moreover, my reconstruction of the Cogito derives strong support from its quite independent philosophical plausibility as an account of mind. Specifically, I argue that the Cogito can be seen as a variant of the Liar paradox. Attention is also given to Kant's closely related arguments concerning the unity of apperception. (shrink)