A general form is proposed for epistemological theories, the relevant factors being: the family of epistemic judgments, the epistemic state, the epistemic commitment (governing change of state), and the family of possible epistemic inputs (deliverances of experience). First a simple theory is examined in which the states are probability functions, and the subject of probability kinematics introduced by Richard Jeffrey is explored. Then a second theory is examined in which the state has as constituents a body of information (rational corpus) and a recipe that determines the accepted epistemic judgments on the basis of this corpus. Through an examination of several approaches to the statistical syllogism, a relation is again established with Jeffrey's generalized conditionalization.

This essay grows out of the conviction that recent work by psychologists studying human reasoning has important implications for a broad range of philosophical issues. To illustrate our thesis we focus on Nelson Goodman's elegant and influential attempt to “dissolve” the problem of induction. In the first section of the paper we sketch Goodman's account of what it is for a rule of inference to be justified. We then marshal empirical evidence indicating that, on Goodman's account of justification, patently invalid inferential rules turn out to be “justified.” We conclude that something is seriously wrong with Goodman's story about justification. In the second section we attempt to patch Goodman's account. The notion of epistemic authority and the social aspect of justification play central roles in the alternative account of justification that we propose.

Some features of physical science relevant for a discussion of physical explanation are mentioned. The D-N account of physical explanation is discussed, and it is seen to restrict the scope of explanation in physical science because it imposes the requirement that the explanandum must be deducible from the explanans. Analysis shows that an alternative view of scientific explanation, called the instance view, allows a wider range of physical explanations. The view is seen to be free from a certain class of counter examples to the D-N theory.

The object of this paper is twofold: to show that resistance to scientific change on the part of scientists need signal neither irrationality nor the presence of extra-scientific influences; and to show how such resistance can be accommodated within a theory of rational choice. After considerations have been outlined suggesting that scientists cannot rationally resist new scientific theories unless theory choice is subjectivistic (section I), evidence is adduced favoring the contrary view (section II). In section III, a non-subjectivistic, non-relativistic conception of rational choice is proposed which recognizes the possibility of scientists' rationally resisting new scientific developments. Finally, in section IV, some minor misunderstandings concerning resistance are discussed.

The so-called post-Wittgensteinian Oxford philosophers are often criticized not only for failing to provide for the causal explanation of human behavior and psychological states, but also for failing to recognize that psychological explanations require appeal to sub-personal or molecular processes. Three strategies accommodating this criticism appear in so-called homunculus theories and include: (1) that the sub-systems be assigned intentional or informational content purely heuristically; (2) that the intentional or informational content of molar states be analyzed without remainder in terms of molecular processing; (3) that the entire or salient range of mental or informational molar states be accessible at the molecular level, or vice versa. Option (2) proves to be the most radical and is favored by Dennett. (1) relevantly requires a reduction of the intentional. (3) is illustrated in various ways by the views of Freud, Chomsky, Fodor. (2) is shown to depend on (1) or to be idle; and (3) embraces at least in part an appeal to molar-level explanation. The argument developed attempts to show the sense in which discourse about molar and molecular-level phenomena in the psychological context is fundamentally different from macroscopic and microtheoretical-level discourse about physical phenomena. The conclusion drawn is that neither a molar nor a sub-personal level theory is suitably explanatory in the psychological sense: a psychological theory is committed rather to a set of sub-personal components of such systems, that serve to explain molar phenomena.

This paper presents an argument for the claim that historical events are unique in a nontrivial sense which entails the inapplicability of the Hempelian D-N model to historical explanations. Some previous criticisms of Hempel are shown to be general criticisms of the D-N model which can be outflanked in cases where a reduction to fundamental laws is available. I then survey grounds for denying that explanations by reasons can be effectively reduced to causal explanations, and for rejecting methodological individualism. I conclude with some positive remarks concerning the structure of historical explanations and sense in which historical events are unique.

Algebraic theories for extensive measurement are traditionally framed in terms of a binary relation ≲ and a concatenation (x,y) → xy. For situations in which the data is “noisy,” it is proposed here to consider each expression y ≲ x as symbolizing an event in a probability space. Denoting P(x,y) the probability of such an event, two theories are discussed corresponding to the two representing relations:with

Axiomatic analyses are given, and representation theorems are proven in detail.

Reichenbach's well-known distinction between the context of discovery and the context of justification has recently come under attack from several quarters. In this paper I attempt to reconsider the distinction and evaluate various recent criticisms of it. These criticisms fall into two main groups: those which directly challenge Reichenbach's distinction; and those which (I argue) indirectly but no less seriously challenge that distinction by rejecting the related distinction between psychology and epistemology, and defending the “naturalizing” of epistemology. I argue that these recent criticisms fail, and that the distinction remains an important conceptual tool necessary for an adequate understanding of the way in which scientific claims purport to appropriately portray our natural environment.

An attractive and apparently indestructible idea about confirmation is that a hypothesis h is confirmed by evidence e if h is a logical consequence of e, or of h and the right sort of other stuff. This idea was advanced in various ways by Ayer (1936), Hempel (1965), Carnap (1959), and still recurs constantly in discussions of confirmation; recently for example, in Schlesinger (1976) and Horwich (1978). The typical modern version of the idea goes like this: a sentence h is confirmed by a sentence e with respect to a theory T if e is true and h & T is consistent and h & T entails e (hereafter, h & T ⊢ e) but T does not entail e (hereafter, T ⊬ e).