According to Philip Kitcher, scientific unification is achieved via the derivation of numerous scientific statements from economies of argument schemata. I demonstrate that the unification of selection phenomena across domains in which it is claimed to occur—evolutionary biology, immunology and, speculatively, neurobiology—is unattainable on Kitcher's view. I then introduce an alternative method for rendering the desired unification based on the concept of a mechanism schema. I conclude that the gain in unification provided by the alternative account suggests that Kitcher's view is defective.

“Modern History” versions of the etiological theory claim that in order for a trait X to have the proper function F, individuals with X must have been recently favored by natural selection for doing F (Godfrey-Smith 1994; Griffiths 1992, 1993). For many traits with prototypical proper functions, however, such recent selection may not have occurred: traits may have been maintained due to lack of variation or due to selection for other effects. I examine this flaw in Modern History accounts and offer an alternative etiological theory, the Continuing Usefulness account, which appears to avoid such problems.

This paper is a defense of “explanatory pluralism” (i.e., the view that some events can be correctly explained in two distinct ways). To defend pluralism, I identify two distinct (but compatible) styles of explanation in paleobiology. The first approach (“actual sequence explanation”) traces out the particular forces that affect each species. The second approach treats the trend as “passive” or “random” diffusion away from a boundary in morphological space. I argue that while these strategies are distinct, some trends are correctly explained in both ways. Further, since neither strategy can be reduced or eliminated from paleobiology, we should accept that both strategies can provide correct explanations for a single trend.

Donald Campbell has long advocated a naturalist epistemology based on a general selection theory, with the scope of knowledge restricted to vicarious adaptive processes. But being a vicariant is problematic because it involves an unexplained epistemic relation. We argue that this relation is to be explicated organizationally in terms of the regulation of behavior and internal state by the vicariant, but that Campbell's selectionist approach can give no satisfactory account of it because it is opaque to organization. We show how organizational constraints and capacities are crucial to understanding both evolution and cognition and conclude with a proposal for an enriched, generalized model of evolutionary epistemology that places high-order regulatory organization at the center.

In this paper I provide a metatheoretical analysis of speech perception research. I argue that the central turning point in the history of speech perception research has not been well understood. While it is widely thought to mark a decisive break with what I call “the alphabetic conception of speech,” I argue that it instead marks the entrenchment of this conception of speech. In addition, I argue that the alphabetic conception of speech continues to underwrite speech perception research today and moreover that it functions as a dogma which ought to be rejected.

The use of null hypothesis significance testing (NHST) in psychology has been under sustained attack, despite its reliable use in the notably successful, so-called “hard” areas of psychology, such as perception and cognition. I argue that, in contrast to merely methodological analyses of hypothesis testing (in terms of “test severity,” or other confirmation-theoretic notions), only a patently metaphysical position can adequately capture the uneven but undeniable successes of theories in “hard psychology.” I contend that Measured Realism satisfies this description, and characterizes the role of NHST in hard psychology.

I analyze the two main theses of Helmholtz's “The Applicability of the Axioms to the Physical World,” in which he argued that the axioms of Euclidean geometry are not, as his neo-Kantian opponents had argued, binding on any experience of the external world. This required two argumentative steps: 1) a new account of the structure of our representations which was consistent both with the experience of our (for him) Euclidean world and with experience of a non-Euclidean one, and 2) a demonstration of why geometric propositions are essentially connected to material and temporal aspects of experience. The effect of Helmholtz's discussion is to throw into relief an intermediate category of metrological objects—objects which are required for the properly theoretical activity of doing physical science (in this sense, a priori requirements for doing science), all while being recognizably contingent aspects of experience.

Credibility in a scientific community (sensu Shapin) is a vicarious selector (sensu Campbell) for the reliability of reports by individual scientists or institutions. Similarly, images from a microscope (sensu Hacking) are vicarious selectors for studying specimens. Working at different levels, the process of indirect reasoning and checking indicates a unity to experimentalist and sociological perspectives, along with a resonance of strategies for assessing reliability. The perspective sketched here can open dialogue between philosophical and sociological interpretations of science and resolves at least one tension regarding the “primary” factors by which scientists evaluate claims.

Functional explanation in the social sciences is the focal point for conflict between individualistic and social modes of explanation. While the agent thought she was acting for reasons, the functional explanation seems to reveal the hidden strings of the puppet master. This essay argues that the conflict is merely apparent. The erotetic model of explanation is used to analyze the forms of intentional action and functional explanations. Two explanations conflict if either the presuppositions of their respective why-questions conflict or the typical answers identified by their relevance criteria conflict. While a functional explanation may have the same topic and foil as an intentional action explanation, both the why-questions and their typical answers are compatible.

This paper defends a social functionalist interpretation, modeled on psychological functionalism, of the meanings of social facts. Social functionalism provides a better explanation of the possibility of interpreting other cultures than approaches that identify the meanings of social facts with either mental states or behavior. I support this claim through a functionalist reinterpretation of sociological accounts of the categories that identify them with their collective representations. Taking the category of causality as my example, I show that if we define it instead in terms of its functional relations to moral rules, it becomes easier to recognize in other cultures.

I shall introduce the units of decision problem in the theory of decision, which as I shall explain is a sibling to the units of selection problem in evolutionary theory. And I shall present an argument to the effect that, contrary to Bayesian wisdom on the subject, undertaking decision in group settings (in multi-individual units) violates no precepts of rationality.

Carter and Leslie (1996) have argued, using Bayes's theorem, that our being alive now supports the hypothesis of an early ‘Doomsday’. Unlike some critics (Eckhardt 1997), we accept their argument in part: given that we exist, our existence now indeed favors ‘Doom sooner’ over ‘Doom later’. The very fact of our existence, however, favors ‘Doom later’. In simple cases, a hypothetical approach to the problem of ‘old evidence’ shows that these two effects cancel out: our existence now yields no information about the coming of Doom. More complex cases suggest a move from countably additive to non-standard probability measures.

The likelihood principle of Bayesian statistics implies that information about the stopping rule used to collect evidence does not enter into the statistical analysis. This consequence confers an apparent advantage on Bayesian statistics over frequentist statistics. In the present paper, I argue that information about the stopping rule is nevertheless of value for an assessment of the reliability of the experiment, which is a pre-experimental measure of how well a contemplated procedure is expected to discriminate between hypotheses. I show that, when reliability assessments enter into inquiries, some stopping rules prescribing optional stopping are unacceptable to both Bayesians and frequentists.

Contemporary Bayesian confirmation theorists measure degree of (incremental) confirmation using a variety of non-equivalent relevance measures. As a result, a great many of the arguments surrounding quantitative Bayesian confirmation theory are implicitly sensitive to choice of measure of confirmation. Such arguments are enthymematic, since they tacitly presuppose that certain relevance measures should be used (for various purposes) rather than other relevance measures that have been proposed and defended in the philosophical literature. I present a survey of this pervasive class of Bayesian confirmation-theoretic enthymemes, and a brief analysis of some recent attempts to resolve the problem of measure sensitivity.

Bayesian psychology, in what is perhaps its most familiar version, is incomplete: Jeffrey conditionalization is not a complete account of rational belief change. Jeffrey conditionalization is sensitive to the order in which the evidence arrives. This order effect can be so pronounced as to call for a belief adjustment that cannot be understood as an assimilation of incoming evidence by Jeffrey's rule. Hartry Field's reparameterization of Jeffrey's rule avoids the order effect but fails as an account of how new evidence should be assimilated.

In the curve fitting problem two conflicting desiderata, simplicity and goodness-of-fit pull in opposite directions. To solve this problem, two proposals, the first one based on Bayes's theorem criterion (BTC) and the second one advocated by Forster and Sober based on Akaike's Information Criterion (AIC) are discussed. We show that AIC, which is frequentist in spirit, is logically equivalent to BTC, provided that a suitable choice of priors is made. We evaluate the charges against Bayesianism and contend that AIC approach has shortcomings. We also discuss the relationship between Schwarz's Bayesian Information Criterion and BTC.