While many philosophers of science have accorded special evidential significance to tests whose results are “novel facts”, there continues to be disagreement over both the definition of novelty and why it should matter. The view of novelty favored by Giere, Lakatos, Worrall and many others is that of use-novelty: An accordance between evidence e and hypothesis h provides a genuine test of h only if e is not used in h's construction. I argue that what lies behind the intuition that novelty matters is the deeper intuition that severe tests matter. I set out a criterion of severity akin to the notion of a test's power in Neyman-Pearson statistics. I argue that tests which are use-novel may fail to be severe, and tests that are severe may fail to be use-novel. I discuss the 1919 eclipse data as a severe test of Einstein's law of gravity.

Darwinians are realists about the force of selection, but there has been surprisingly little discussion about what form this realism should take. Arguments about the units of selection in general and genic selectionism in particular reveal two realist assumptions: (1) for any selection process, there is a uniquely correct identification of the operative selective forces and the level at which each impinges; and (2) selective forces must satisfy the Pareto-style requirement of probabilistic causation. I argue that both assumptions are false; we must temper realism about the force of selection and revise the way we think about probabilistic causation.

Maher (1988, 1990) has recently argued that the way a hypothesis is generated can affect its confirmation by the available evidence, and that Bayesian confirmation theory can explain this. In particular, he argues that evidence known at the time a theory was proposed does not confirm the theory as much as it would had that evidence been discovered after the theory was proposed. We examine Maher's arguments for this “predictivist” position and conclude that they do not, in fact, support his view. We also cast doubt on the assumptions of Maher's alleged Bayesian proofs.

Rosenberg argues that intentional generalizations in the human sciences cannot be law-like because they are not amenable to significant empirical refinement. This irrefinability is said to result from the principle that supposedly controls in intentional explanation also serving as the standard for successful interpretation. The only credible evidence bearing on such a principle would then need conform to it. I argue that psychological generalizations are refinable and can be nomic. I show how empirical refinement of psychological generalizations is possible by considering concrete cases. A sufficiently detailed view of the role of psychological generalizations in interpretation allows us to find in psychological investigations instances of bootstrap testing.

Modernism in the philosophy of science demands a unified story about what makes an inquiry scientific (or a successful science). Fine's “natural ontological attitude” (NOA) is “postmodern” in joining trust in local scientific practice with suspicion toward any global interpretation of science to legitimate or undercut that trust. I consider four readings of this combination of trust and suspicion and their consequences for the autonomy and cultural credibility of the sciences. Three readings take respectively Fine's trusting attitude, his emphasis upon local practice, and his antiessentialism about science as most fundamental to NOA. A fourth, more adequate reading, prompted by recent feminist interpretations of science, offers less restrictive readings of both Fine's trust and his suspicion toward approaching science with “ready-made philosophical engines” (Fine 1986b, 177).

Based partly on proving that algebraic relativistic quantum field theory (ARQFT) is a stochastic Einstein local (SEL) theory in the sense of SEL which was introduced by Hellman (1982b) and which is adapted in this paper to ARQFT, the recently proved maximal and typical violation of Bell's inequalities in ARQFT (Summers and Werner 1987a–c) is interpreted in this paper as showing that Bell's inequalities are, in a sense, irrelevant for the problem of Einstein local stochastic hidden variables, especially if this problem is raised in connection with ARQFT. This leads to the question of how to formulate the problem of local hidden variables in ARQFT. By giving a precise definition of hidden-variable theory within the operator algebraic framework of quantum mechanics, it will be argued that the aim of hidden-variable investigations is to determine those classes of quantum theories whose elements represent a statistical content that cannot be reduced in a given way. In some particular way to be stated, a proposition will be stated which distinguishes quantum field theories whose statistical content cannot be reduced without violating some relativistic locality principle.

The concept underlying Prigogine's ideas is the asymmetric “lifetime” he introduces into thermodynamics in addition to the symmetric time parameter. By identifying processes by means of causal chains of genidentical events, we examine the intrinsic order of lifetime adopting Grünbaum's symmetric time order. Further, we define the physical meaning and the actuality of the processes under consideration. We conclude that Prigogine's microscopic temporal irreversibility is tacitly assumed at macroscopic level. Moreover, his “new” complementarity lacks any scientific foundation. Finally, we put forward the fact-like origin of temporal irreversibility referring to classical thermodynamics.

Jarrett Leplin has recently criticized a number of aspects of my views of the aims and goals of science, of the rationale of scientific change, and of the consequent relations between science and the philosophy of science, and in particular of the methodology of the latter (Leplin 1984, 1987, 1988a, 1988b). Here I will respond to those criticisms, and also reply to some related criticisms made by other writers.

In his article, “Is Essentialism Unscientific?” (1988), Jarrett Leplin claims that I do not have sufficient grounds for rejecting the customary “philosophical method of discovery” that allows for the direct transfer of theories developed in the philosophy of language to science. While admitting that all attempts at transfer thus far have failed, he still maintains that method is sound. I argue that the wholesale failure of these attempts is reason enough to suspect the method and to try to devise one more suitable to fathoming how “meaning”, “reference”, and “meaning change” are to be understood for scientific theories. The method I have proposed in Nersessian (1984b), and subsequent work, demands that we learn how to incorporate the actual practices of meaning construction in science into our analyses. Leplin distorts my analysis and, thus, fails to understand the insights that study provides.

Alan Garfinkel (1981) and Bas van Fraassen (1980), among others, have proposed a contrastive theory of explanation, according to which the proper form of an explanatory why-question is not simply “Why P?” but “Why P rather than Q?”. Dennis Temple (1988) has argued in this journal that the contrastive explanandum “P rather than Q” is equivalent to the conjunction, “P and not-Q”. I show that the contrast is not equivalent to the conjunction, nor to other plausible noncontrastive candidates. I then consider David Lewis's (1986) proposal for the way contrasts determine an explanatory cause, which does not require recasting the contrastive explanandum. Lewis's proposal is found to be unacceptable, but it suggests an improvement that shows contrastive explanations to employ a mechanism of “causal triangulation”, similar to Mill's method of difference.