With the ever-growing quality of observational data in astronomy, the complexity of astrophysical models has been increasing in turn. This trend raises the question: Are there still reasons to prefer simpler models if the final goal is an actual model-target comparison? I argue for two aspects in which astrophysical research may favor models having reduced complexity: first, to address the problem of determining the values of adjustable parameters and, second, to pave the way for a validation of the model based on the modeler’s understanding of the scope of the model and the critical processes on the target’s side.

Genic selectionists (Williams 1966; Dawkins 1976) defend the view that genes are the (unique) units of selection and that all evolutionary events can be adequately represented at the genic level. Pluralistic genic selectionists (Sterelny and Kitcher 1988; Waters 1991; Dawkins 1982) defend the weaker view that in many cases there are multiple equally adequate accounts of evolutionary events, but that always among the set of equally adequate representations will be one at the genic level. We describe a range of cases all involving stable equilibria actively maintained by selection. In these cases genotypic models correctly show that selection is active at the equilibrium point. In contrast, the genic models have selection disappearing at equilibrium. For deterministic models this difference makes no difference. However, once drift is added in, the two sets of models diverge in their predicted evolutionary trajectories. Thus, contrary to received wisdom on this matter, the two sets of models are not empirically equivalent. Moreover, the genic models get the facts wrong.

I consider the following questions, central to recent disagreements between Longino and Kitcher: Is it constitutive of making judgments of the cognitive acceptability of theories that they are made under certain social relations that embody specific social values that have been cultivated among investigators (Longino)? Or is making them (sound ones) just a consequence of social interactions that occur under these relations (Kitcher)? While generally endorsing the latter view, I make a distinction, not made by the philosophers under discussion, between sound acceptance and endorsement of a theory, and argue that Longino's view applies to endorsement.

The measurement of force is based on a formal law of additivity, which characterizes the effects of two or more configurations on the equilibrium of a material point. The representing vectors (resultant forces) are additive over configurations. The existence of a tight interrelation between the force vector and the geometric space, in which motion is described, depends on observations of partial (directional) equilibria; an axiomatization of this interrelation yields a proof of part two of Newton's second law of motion.

The present results (which were derived from a curious and deep isomorphism between force measurement and trichromatic color measurement) yield a kind of subunit, which needs to be incorporated into more complete axiomatizations of mechanics that would fulfill the Mach–Kirchhoff program.

In a previous article, we have demonstrated by a general phase space argument that a Maxwellian Demon is compatible with statistical mechanics. In this article, we show how this idea can be put to work in the prevalent model of the Demon, namely, a particle-in-a-box, used, for example, by Szilard and Bennett. In the literature, this model is used in order to show that a Demon is incompatible with statistical mechanics, either classical or quantum. However, we show that a detailed phase space analysis of this model illustrates that a Maxwellian Demon is compatible with statistical mechanics.

Probability and Frequency. Aristotle frequently used the concept of probability, but apparently he did not make any persistent effort to clarify or analyze it. His description of a fortiori argument in The Topics (115a, 6–14), e.g., depends upon “the more or less likely or probable,” but he does not explore this notion. In The Rhetoric, where he applies himself to a puzzle about probability which the Sophists had advanced (1402a, 5–30), he comes closer to an analysis of probability. Aristotle quotes Agathon,

This paper argues against the possibility of presenting a consistent version of the Copenhagen Interpretation of Quantum Physics, characterizing its founders' philosophical pronouncements including those on the realism-antirealism issue, as a contingent collection of local, often contradictory, moves in changing theoretical and sociopolitical circumstances. The paper analyzes the fundamental differences of opinion between Bohr and the mathematical physicists, Heisenberg and Born, concerning the foundational doctrine of the “indispensability of classical concepts”, and their related disagreements on “quantum reality.” The paper concludes with an explanation of how the appearance of consensus was achieved despite fundamental disagreements among the proponents. The paper undermines the adequacy of the notion of a general conceptual framework to describe the philosophical endeavors of working scientists.

Scientists can choose different claims as interpretations of the results of their research. Scientific rhetoric is understood as the attempt to make those claims most beneficial for the scientists’ interests. A rational choice, game-theoretic model is developed to analyze how this choice can be made and to assess it from a normative point of view. The main conclusion is that ‘social’ interests (pursuit of recognition) may conflict with ‘cognitive’ ones when no constraints are put on the choices of the authors of scientific papers, as in an ‘ideal free speech situation’. Scientific institutions may help to solve this conflict. Lastly, some empirical predictions are offered that can inspire future social research of the refereeing process.

In “Resurrecting Biological Essentialism,” I went against the consensus in the philosophy of biology by arguing that a Linnaean taxon, including a species, has an essence that is, at least partly, an underlying intrinsic, mostly genetic, property: this intrinsic nature explains both the truth of generalizations about the phenotypic properties of the taxon and why being in the taxon is explanatory. The current article is a response to two criticisms: that this intrinsic essentialism is at odds with certain biological variations and that this talk of intrinsic essences is an uncalled for metaphysical addition to biology.

Roger Jones asks what Newtonian realists should be realists about, given that there are four empirically equivalent formulations of Newtonian mechanics which have different ontological commitments and explanatory mechanisms. A realist answer is sketched: Newtonians should be realists about what the best metaphysical considerations dictate, where the best metaphysical considerations are those which have yielded the best physics. Metaphysical considerations are required within physics, just as they are required to eliminate idealist and surrealist theories which are empirically equivalent to realist ones. Realists must reject the positivist assumption that empirically equivalent theories are explanatory and evidential equivalents, too.

When can one say that a new theory is truer than the old one it contradicts, even though neither is absolutely true? We are primarily concerned with the case in which the conflicting theories offer answers to the same questions, and so we do not introduce considerations of “logical width”. We propose that part of the new theory is truer than part of the old one when the former part gets right whatever the latter part got right while the former does not make any new mistakes. Pragmatic considerations will determine the relative importance of whatever new mistakes the new theory does make as a whole. To avoid artificial counterexamples, we restrict the parts compared to those that are “convex”. A “convex” theory is one that holds in all cases intermediate between any two cases in which it holds.

Let us invoke philosophic license for a moment to suppose you receive the following letter:

“Dear Sir:

I am taking the liberty of calling upon you to be the judge in a dispute between me and an acquaintance who is no longer a friend. The question at issue is this: Is my creation, umbrellaology, a science? Allow me to explain this situation. For the past eighteen years, assisted by a few faithful disciples, I have been collecting materials on a subject hitherto almost wholly neglected by scientists, the umbrella. The results of my investigations to date are embodied in the nine volumes which I am sending to you under separate cover. Pending their receipt, let me describe to you briefly the nature of their contents and the method I pursued in compiling them. I began on the Island of Manhattan. Proceeding block by block, house by house, family by family and individual by individual I ascertained 1) the number of umbrellas possessed, 2) their size, 3) their weight, 4) their color. Having covered Manhattan after many years, I eventually extended the survey to the other boroughs of the City of New York, and at length completed the entire city. Thus I was ready to carry forward the work to the rest of the state and indeed the rest of the United States and the whole known world.

Recent defenses of a priori knowledge can be applied to the idea of conventions in science in order to indicate one important sense in which conventionalism is correct—some elements of physical theory have a unique epistemological status as a functionally a priori part of our physical theory. I will argue that the former a priori should be treated as empirical in a very abstract sense, but still conventional. Though actually coming closer to the Quinean position than recent defenses of a priori knowledge, the picture of science developed here is very different from that developed in Quinean holism in that categories of knowledge can be differentiated.

Many have claimed that split-brain patients are actually two persons. I maintain that both the traditional separation argument and the more recent sophistication argument for the two persons interpretation are inadequate on conceptual grounds. An autonomy argument is inadequate on empirical grounds. Overall, theoretical and practical consequences weigh heavily in favor of adopting a one person interpretation.

This paper is an attempt at a vindication of induction. The point of departure is that induction requires a justification and that the only kind of justification possible is a vindication. However traditional vindications of induction have rested on unjustified assumptions about the aim of induction. This vindication takes the end pursued in induction simply to be correct prediction. It is argued that induction is the only reasonable way of pursuing this end because induction is the only objective method of predicting. While objectivity is not a necessary condition for successful predicting, it is a sufficient condition for the possession of a property that is, in turn, a necessary condition for correct predicting; and further there could be no reason to expect any non-objective method to possess this necessary condition for success.

Induction is the only objective method of predicting for it alone uses facts which must be identified by any predicting method based on rules; and it alone uses these facts according to a relationship that must hold between facts and any meaningful empirical statement. Any alternative to induction must assume that the factual regularities that have been detected will alter in the future and the way they are expected to alter must be arbitrary. It is further claimed that this vindication is proof against the criticisms that have been advanced against practicalist justifications of induction.

It is the aim of this paper to examine certain aspects of a point of view which has attracted much attention in physical methodology. This is the standpoint known as operationalism. We wish to discuss its significance in the construction and interpretation of physical theories.

The essential meaning of operationalism in physics is that physical concepts should be defined in terms of actual physical operations. On this view there is no meaning to a concept unless it represents an operation which can be performed in the laboratory. Thus the term “pressure of a gas” signifies nothing until an operation is described which constitutes the measurement of pressure. When one thinks of pressure one must think. of some actual apparatus, such as, for example, some glass and rubber tubing and some mercury and certain operations performed using these until finally one gets a pointer reading which one calls the pressure of the gas. The same stand is taken with respect to length, time, velocity, acceleration, temperature, etc.

In this article I articulate the Theory of Affective Pragmatics, which combines insights from the Basic Emotion View and the Behavioral Ecology View of emotional expressions. My core thesis is that emotional expressions are ways of manifesting one’s emotions but also of representing states of affairs, directing other people’s behaviors, and committing to future courses of actions. Since these are some of the main things we can do with language, my article’s take home message is that, from a communicative point of view, much of what we can do with language we can also do with nonverbal emotional expressions.

The new field of meta-research investigates industry bias, publication bias, contradictions between studies, and other trends in medical research. I argue that its findings should be used as meta-evidence for evaluating therapies. ‘Meta-evidence’ is evidence about the support that direct ‘first-order evidence’ provides the hypothesis. I consider three objections to my proposal: the irrelevance objection, the screening-off objection, and the underdetermination objection. I argue that meta-research evidence works by rationally revising our confidence in first-order evidence and, consequently, in the hypothesis—typically, downward.

I argue that 'c' occurs extensionally in 'c caused e' and 'D' occurs extensionally in 'c caused e because c is D'. I claim that this has been insufficiently appreciated because the two contexts are often run together and because it has not been clear that the description D of c is among the referents of an explanatory argument. I argue as well that Hume's analysis of causation is consistent with taking causation to be a relation between single events, and that even if events are eliminated as virtual entities, extensionality holds for all terms in the resulting context.