The degree of confirmation assigned to any given hypothesis is sensitive to properties of the entire belief system … simplicity, plausibility, and conservatism are properties that theories have in virtue of their relation to the whole structure of scientific beliefs taken collectively. A measure of conservatism or simplicity would be a metric over global properties of belief systems.

Suppose that the organism is given the problem of determining the analysis of a stimulus at a certain level of representation- e.g., the problem of determining which sequence of words a given utterance encodes. Since, in the general case, transducer outputs underdetermine perceptual analyses, we can think of the solution of such problems as involving processes of non-demonstrative inference. In particular, we can think of each input system as a computational mechanism which projects and confirms a certain class of hypotheses on the basis of a certain body of data.

The data that can bear on the confirmation of perceptual hypotheses includes, in the general case, considerably less than the organism may know.

I hate relativism. I hate relativism more than I hate anything else, excepting, maybe, fiberglass powerboats... surely, surely, no one but a relativist would drive a fiberglass powerboat.

This monograph is about the current status of the program; not so much its evidential status (which I take to be, for the most part, an open question ) as what the program is and where it does, and doesn't, seem natural to try to apply it. Specifically I want to do the following things: (1) distinguish the general claim that there are psychological faculties from a particular version of that claim, which I shall call the modularity thesis; (2) enumerate some of the properties that modular cognitive systems are likely to exhibit in virtue of their modularity ; and (3) consider whether it is possible to formulate any plausible hypothesis about which mental processes are likely to be the modular ones. Toward the end of the discussion, I'll also try to do something by way of (4) disentangling the faculty jmodularity issues from what I'll call the thesis of Epistemic Boundedness: the idea that there are endogenously determined constraints on the kinds of problems that human beings can solve, hence on the kinds of things that we can know.

If there is a community of computers living in my head, there had also better be somebody who is in charge; and, by God, it had better be me.

If people differ in an absolutely general way in their estimations of epistemic relevance, and if we follow the holism of meaning and individuate intentional states by way of the totality of their epistemic bonds, the consequence will be that two people (or, for that matter, two temporal sections of the same person) will never be in the same intentional state. Therefore, two people can never be subsumed under the same intentional generalizations. And, therefore, intentional generalization can never be successful. And, therefore again, there is no hope for an intentional psychology.

When taken as a way of modeling cognitive architecture, really does represent an approach that is quite different from that of the classical cognitive science that it seeks to replace. Classical models of the mind were derived from the structure of Turing and Von Neumann machines. They are not, of course, committed to the details of these machines as exemplified in Turing's original formulation or in typical commercial computers—only to the basic idea that the kind of computing that is relevant to understanding cognition involves operations on symbols.. In contrast, connectionists propose to design systems that can exhibit intelligent behavior without storing, retrieving, or otherwise operating on structured symbolic expressions. The style of processing carried out in such models is thus strikingly unlike what goes on when conventional machines are computing some function.

FACULTY PSYCHOLOGY is getting to be respectable again after centuries of hanging around with phrenologists and other dubious types. By faculty psychology I mean, roughly , the view that many fundamentally different kinds of psychological mechanisms must be postulated in order to explain the facts of mental life . Faculty psychology takes seriously the apparent heterogeneity of the mental and is impressed by such prima facie differences as between, say, sensation and perception, volition and cognition, learning and remembering, or language and thought.

From the point of view of semantics, errors must be accidents: if in the extension of "horse" there are no cows, then it cannot be required for the meaning of "horse" that cows be called horses. On the other hand, if "horse" did not mean that which it means, and if it were an error for horses, it would never be possible for a cow to be called "horse." Putting the two things together, it can be seen that the possibility of falsely saying "this is a horse" presupposes the existence of a semantic basis for saying it truly, but not vice versa. If we put this in terms of the crude causal theory, the fact that cows cause one to say "horse" depends on the fact that horses cause one to say "horse"; but the fact that horses cause one to say "horse" does not depend on the fact that cows cause one to say "horse"...

Philosophers who have wanted to banish the ghost from the machine have usually sought to do so by showing that truths about behavior can sometimes, and in some sense, logically implicate truths about mental states. In so doing, they have rather strongly suggested that the exorcism can be carried through only if such a logical connection can be made out. ... Once it has been made clear that the choice between dualism and behaviorism is not exhaustive, a major motivation for the defense of behaviorism is removed: we are not required to be behaviorists simply in order to avoid being dualists.