Leeds (1990) levels an objection against the criterion of rational choice I have proposed (Levi 1997, Ch. 6; 1980; 1986), pointing out that the criterion is sensitive to the way possible consequences are partitioned. Seidenfeld, Kadane and Schervish (1989) call into question the defense of the cross product rule by appeal to Pareto Unanimity Principles that I had invoked in my 1986. I offer clarifications of my proposals showing that the difference between my views and those of my critics concerns the extent to which full belief, probabilistic belief, and value judgment are separable.

Recent models using simple signaling games provide a theoretical setting for investigating the evolutionary connection between signaling and behavioral plasticity. These models have shown that plasticity is typically eliminated in common-interest signaling games. In many real cases of signaling, however, interests do not align. Here, I present a model of the evolution of plasticity in signaling games and consider games of common, opposed, and partially aligned interests. I find that the setting of partial common interest is most conducive to the evolution of plasticity. Plastic individuals succeed by learning when to deceive others and when to trust others’ signals.

Although the canonical distribution is one of the central tools of statistical mechanics, the reason for its effectiveness is poorly understood. This is due in part to the fact that there is no clear consensus on what it means to use the canonical distribution to describe a system in equilibrium with a heat bath. I examine some traditional views as to what sort of thing we should take the canonical distribution to represent. I argue that a less explored alternative, according to which the canonical distribution represents a time ensemble of sorts, has a number of advantages that rival interpretations lack.

It would appear that among scientific men discussion of the general principles of natural science (including the problem of causation) has, on the whole, proved more congenial to mathematicians (with their brothers-in-arms the logicians) and physicists than to biologists. Just why this should be so might be difficult to explain or justify. But one reason seems to lie in the comparative ambiguity of the concept of causation in biology. In general, the term causation has been used in science to designate the special rôle of active factors, rather than of passive or stable factors (more or less permanent “conditions”), in the determination of single events. By active factors we mean those which involve physical change, typically associated with transfer of energy; these are distinguished from stable factors or invariants which persist unchanged throughout the process under consideration. Thus in the classical isolated system, the total energy represents a stable factor which remains the same through all transformations of the system. The energy changes its form, potential or distribution, but not its total quantity. This rule of conservation defines a static condition persisting as a limiting factor through any case of change. Similarly, the permanent or unchanging factor in a machine consists in the stable properties and structural interconnections of its parts; together those constitute an invariant which fixes definitely the possible range of activity. Activity itself requires flow of energy; strictly speaking, a causal factor is not a static factor but is a change of some kind; releasing events (“trigger action”) are included under causal events since they introduce factors without which change does not occur.

In what follows, I critique the interpretation that Sober and Wilson offer of their group selection model in Unto Others. Sober and Wilson mistakenly claim that their model operates as an example of Simpson's paradox and defend an interpretation of their model according to which groups are operated upon by natural selection. In the place of their interpretation, I offer one that parallels the mathematical calculation of the model's outcome and does not depend on the postulation of a force of group selection or a value for group fitness.

Charles Peirce was one of those rare individuals, an expert logician who is at the same time an experienced practical scientist. His logical acumen was apparent even to his contemporaries; while an early training in chemistry, astronomy, geodesy and optics, left him, as he declares, “saturated through and through with the spirit of the physical sciences.“ One is therefore hardly surprised to discover that he was deeply interested in scientific methodology—particularly in the logic of induction. Indeed, it would not be an exaggeration to say that some of his most significant contributions to philosophy were made in precisely this field. No apology is thus required for devoting attention to them. In the present paper I want to sketch his treatment of induction very briefly, and attempt a tentative estimate of its validity.

M. H. A. Newman (1928) criticized Russell's structuralist philosophy of science. Demopoulos and Friedman have discussed Newman's critique, showing its relevance to the structuralist positions held by Schlick and Carnap, and to Putnam's argument against “metaphysical realism”. I discuss Richard Braithwaite's (1940) appeal to Newman in a critique of Arthur Eddington. Braithwaite believed Newman had shown that “structure depends upon content”. Eddington, in his reply, misunderstood the generality of Newman's argument.

In this article, I consider what sorts of chance credence norms can be justified by appeal to the idea that ideal credences should line up with the chances. I argue that the Principal Principle cannot be so justified but that an alternative norm, the Temporal Principle—which maintains that an agent’s credence in a proposition ϕ, conditional on the temporal proposition that says that the chance of ϕ is x, should be x—can be so justified.

According to Marr's theory of vision, computational processes of early vision rely for their success on certain “natural constraints” in the physical environment. I examine the implications of this feature of Marr's theory for the question whether psychological states supervene on neural states. It is reasonable to hold that Marr's theory is nonindividualistic in that, given the role of natural constraints, distinct computational theories of the same neural processes may be justified in different environments. But to avoid trivializing computational explanations, theories must respect methodological solipsism in the sense that within a theory there cannot be differences in content without a corresponding difference in neural states.

Theories in the usual sense, as characterized by a language and a set of theorems in that language (“statement view”), are related to theories in the structuralist sense, in turn characterized by a set of potential models and a subset thereof as models (“non-statement view”, J. Sneed, W. Stegmüller). It is shown that reductions of theories in the structuralist sense (that is, functions on structures) give rise to so-called “representations” of theories in the statement sense and vice versa, where representations are understood as functions that map sentences of one theory into another theory. It is argued that commensurability between theories should be based on functions on open formulas and open terms so that reducibility does not necessarily imply commensurability. This is in accordance with a central claim by Stegmüller on the compatibility of reducibility and incommensurability that has recently been challenged by D. Pearce.

Mechanistic explanations satisfy widely held norms of explanation: the ability to manipulate and answer counterfactual questions about the explanandum phenomenon. A currently debated issue is whether any nonmechanistic explanations can satisfy these explanatory norms. Weiskopf argues that the models of object recognition and categorization, JIM, SUSTAIN, and ALCOVE, are not mechanistic yet satisfy these norms of explanation. In this article I argue that these models are mechanism sketches. My argument applies recent research using model-based functional magnetic resonance imaging, a novel neuroimaging method whose significance for current debates on psychological models and mechanistic explanation has yet to be explored.

The nature of time is one of the crucial problems in the philosophy of science and it cannot be solved by an appraisal of past formulations of the time concept, nor by introspective examination of our awareness of time. Among the philosopher's tasks is the seemingly thankless one of scrutinizing the advance of modern science for significant facts and ideas, and to integrate these into the larger notions he has formed of time. Recent physics bears suggestions of peculiar interest in this regard; chief among them is the theory of quantum electrodynamics developed by Feynman which involves reversals in the course of time and thereby cherishes, in the minds of many, an age-old phantasy of more than scientific appeal. To appraise that theory in philosophic terms is the purpose of this note.

This paper compares human diversity with biological diversity generally. Drawing on the pluralistic perspective on biological species defended in earlier work (2002, chs. 3 and 4), I argue that there are useful parallels to be drawn between human and animal kinds, as there are between their respective sources in cultural evolution and evolution generally. This view is developed in opposition to the insistence by sociobiologists and their successors on minimizing the significance of culture. The paper concludes with a discussion of the relation between cultural difference and individual difference, and the relation of the latter to conceptions of human freedom.

In this paper we examine Ellis and Bowman's argument, that simultaneity in inertial frames of reference is not conventional, from the axiomatic point of view. In Part I we examine the role of conventions in an axiomatic physical theory, and in Part II the relation of simultaneity in Reichenbach's axiomatization of the space-time theory of special relativity.

The interpretation of the calculus of probability as a logic of partial belief has at least two advantages: it makes the assignment of probabilities plausible in cases where classical frequentist interpretations must find such assignments meaningless, and it gives a clear meaning to partial belief and to consistency of partial belief.

Modal interpretations are hidden-variable, no-collapse interpretations of quantum mechanics that were designed to solve the measurement problem and reconcile this theory with relativity. Yet, as no-go theorems by Dickson and Clifton (1998), Arntzenius (1998) and Myrvold (2002) demonstrate, current modal interpretations are incompatible with relativity. In the mainstream modal interpretations, properties of composite systems are generally unrelated to the properties of their subsystems. We propose holistic and relational interpretations of properties to explain this failure of property composition. Based on these interpretations, we consider strategies for circumventing Myrvold's theorem, which are also effective against the other two theorems.

1. Introduction. One major concern in cognitive psychology is explaining cognitively motivated behavior. However, attempts to specify the nature of the behavior that psychology is to explain have proved to be somewhat controversial. The aim of this paper is to conduct a preliminary investigation into the kinds of behavior psychology is (or should be) concerned with.

The attribute of living is due either to a specific state of matter or to a distinctive kind of energy. All possible interpretations of these two concepts are materialistic with one exception. There is said to be a kind of energy apart from this world. Such an assumption is vitalistic.

There does not seem to be a consistent way to ground the concept of “force” in Cartesian first principles. In this article, I first review the literature on the subject. Then, I offer an alternative interpretation of force—one that seems to be coherent and consistent with Descartes’ project. Not only does the new position avoid the problems of previous interpretations, but it does so in such a way as to support and justify those previous interpretations.