Terry Horgan

Reliablists have argued that the important evaluative epistemic concept of being justified in holding a belief, at least to the extent that that concept is associated with knowledge, is best understood as concerned with the objective appropriateness of the processes by which a given belief is generated and sustained. In particular, they hold that a belief is justified only when it is fostered by processes that are reliable (at least minimally so) in the believer’s actual world.[1] Of course, reliablists typically recognize other concepts of justification--typically subjective notions--which are given a noncompeting sort of epistemic legitimacy. However, they have tended to focus on the epistemically central notion of "strong justification," and have come to settle on this familiar reliablist analysis, supposing that it pretty much exhausts what there is to say about "objective justification.".

  David Marr provided a useful framework for theorizing about cognition within classical, AI-style cognitive science, in terms of three levels of description: the levels of (i) cognitive function, (ii) algorithm and (iii) physical implementation. We generalize this framework: (i) cognitive state transitions, (ii) mathematical/functional design and (iii) physical implementation or realization. Specifying the middle, design level to be the theory of dynamical systems yields a nonclassical, alternative framework that suits (but is not committed to) connectionism. We consider how a brain's (or a network's) being a dynamical system might be the key both to its realizing various essential features of cognition — productivity, systematicity, structure-sensitive processing, syntax — and also to a non-classical solution of (frame-type) problems plaguing classical cognitive science

David Marr provided an influential account of levels of description in classical cognitive science. In this paper we contrast Marr'ent with some alternatives that are suggested by the recent emergence of connectionism. Marr's account is interesting and important both because of the levels of description it distinguishes, and because of the way his presentation reflects some of the most basic, foundational, assumptions of classical AI-style cognitive science . Thus, by focusing on levels of description, one can sharpen foundational differences between classicism and potential non-classical conceptions of mentality that might emerge under the rubric of connectionism

Folk psychological realism is the view that folk psychology is true and that people really do have propositional attitudes, whereas anti-realism is the view that folk psychology is false and people really do not have propositional attitudes. We argue that anti-realism is not worthy of acceptance and that realism is eminently worthy of acceptance. However, it is plainly epistemically possible to favor either of two forms of folk realism: scientific or non-scientific. We argue that non-scientific realism, while perhaps unpopular among philosophers of mind, is a distinct form of realism from scientific realism, and that it is not yet knowable whether scientific or non-scientific realism is true. We also outline how adopting realism, but remaining neutral between scientific and non-scientific realism, offers fresh insights into such topics as instrumentalism, supervenience, the language of thought hypothesis, and elimin-ativism.

I explain why, within the nonclassical framework for cognitive science we describe in the book, cognitive-state transitions can fail to be tractably computable even if they are subserved by a discrete dynamical system whose mathematical-state transitions are tractably computable. I distinguish two ways that cognitive processing might conform to programmable rules in which all operations that apply to representation-level structure are primitive, and two corresponding constraints on models of cognition. Although Litch is correct in maintaining that classical cognitive science is not committed to the first constraint, it is committed to the second. This fact constitutes an illuminating gloss on our claim that one foundational assumption of classicism is that human cognition conforms to programmable, representation-level, rules

I invoked the notion of supervenience in my doctoral disseration, Microreduction and the Mind-Body Problem, completed at the University of Michigan in 1974 under the direction of Jaegwon Kim. I had been struck by the appeal to supervenience in Hare (1952), a classic work in twentieth century metaethics that I studied at Michigan in a course on metaethics taught by William Frankena; and I also had been struck by the brief appeal to supervenience in Davidson (1970). Kim was already, in effect, construing the relation between physical and mental properties as a supervenience relation?although he was not yet using the word ?supervenience?. I assumed that a materialistic metaphysics was correct, and that integral to materialism is the idea that higher-level sciences (including psychology) are reducible to lower-level ones?ultimately to microphysics. One idea I pressed in the dissertation was that biconditional ?bridge laws? would not suffice for genuine intertheoretic reduction if these inter-level laws were additional fundamental laws of nature alongside those of the reducing science; they would be what Herbert Feigl and J.J. C. Smart, in their writings on the psychophysical identity theory, called ?nomological danglers.? I argued that the higher-level property in a bridge law should bear a relation of strict supervenience to its correlated lower-level property, rather than merely being nomically correlated with it. The basic idea was that there are no two physically possible worlds w1 and w2?where a physically possible world is, roughly, a world in which the laws of microphysics obtain and in which there are no nonphysical substances like entelechies or Cartesian souls?such that the actual-world bridge laws obtain in world w1 but not in world w2. (Thus, the bridge laws themselves are fixed relative to the fundamental physical facts and fundamental laws, rather than being fundamental laws themselves alongside those of microphysics.) Already when