This paper shows that species are individuals with respect to evolutionary theory in the sense that the laws of the theory deal with species as irreducible wholes rather than as sets of organisms. ‘Species X’ is an instantiation of a primitive term of the theory. I present a sketch of a proof that it cannot be defined within the theory as a set of organisms; the proof relies not on details of my axiomatization but rather on a generally accepted property of speciation; hence the same argument should work for any axiomatization which captures this generally accepted property of speciation.

Biology lacks a central organism concept that unambiguously marks the distinction between organism and non-organism because the most important questions about organisms do not depend on this concept. I argue that the two main ways to discover useful biological generalizations about multicellular organization—the study of homology within multicellular lineages and of convergent evolution across lineages in which multicellularity has been independently established—do not require what would have to be a stipulative sharpening of an organism concept.

Many of the arguments against reductionism and fundamental theory as a method for explaining physical phenomena focus on the role of models as the appropriate vehicle for this task. While models can certainly provide us with a good deal of explanatory detail, problems arise when attempting to derive exact results from approximations. In addition, models typically fail to explain much of the stability and universality associated with critical point phenomena and phase transitions, phenomena sometimes referred to as “emergent.” The paper examines the connection between theoretical principles like spontaneous symmetry breaking and emergent phenomena and argues that new ways of thinking about emergence and fundamentalism are required in order to account for the behavior of many phenomena in condensed matter and other areas of physics.

Experimental observations are often taken in order to assist in making a choice between relevant hypotheses ~H and H. The power of observations in this decision is here metrically defined by information-theoretic concepts and Bayes' theorem. The exact (or maximum power) of a new observation to increase or decrease Pr(H) the prior probability that H is true; the power of that observation to modify the total amount of uncertainty involved in the choice between ~H and H: the power of a new observation to reduce uncertainty toward the ideal amount, zero; all these powers are systematically shown to be exact metrical functions of

where the numerator is the likelihood of the new observation given H, and the denominator is the “expectedness” of the observation.

The violation of the Bell inequality means that measurement-results in the two wings of the experiment cannot be screened off from one another, in the sense of Reichenbach. But does this mean that there is causation between the results? I argue that it does, according to Lewis's counterfactual analysis of causation and his associated views. The reason lies in his doctrine that chances evolve by conditionalization on intervening history. This doctrine collapses the distinction between the conditional probabilities that are used to state screening off, and the counterfactuals with chance consequents that are used to state lack of causation. I briefly discuss ways to evade my argument.

In biology, the ‘ecological orientation’ rests on a commitment to examining systems, and the conceptual challenge of defining that system now employs techniques and concepts adapted from diverse disciplines (i.e., systems philosophy, cybernetics, information theory, computer science) that are applied to biological simulations and model building. Immunology has joined these efforts, and the question posed here is whether the discipline will remain committed to its theoretical concerns framed by the notions of protecting an insular self, an entity demarcated from its environment, or will shift its focus of interest to a wider context. An ecological perspective emphasizes the interchange between the organism and its environment, the processing of information, and the regulation arising from responses to this larger context. Moving from the first attempts at modeling the immune system as a closed network, immunologists have joined the general interest in systems analysis, and that move might portend a significant shift to an open, more holistic consideration of immune regulation.

Past criticisms to the contrary, methodological individualism in the social sciences is neither trivial nor obviously false. In the style of Weber's sociology, it restricts the ultimate explanatory repertoire of social science to agents' reasons for action. Although this restriction is not obviously false, it ought not to be accepted, at present, as a regulative principle. It excludes, as too far-fetched to merit investigation, certain hypotheses concerning the influence of objective interests on large-scale social phenomena. And these hypotheses, in fact, merit empirical consideration. The attractiveness of methodological individualism as a regulative principle depends on two independent confusions, the conflation of an agent's reasons for action with the beliefs, needs, desires, or goals which are the reasons why he acted as he did, and the identification of explaining a phenomenon and describing its causes.

Some scientific realists suggest that scientific communities have improved in their ability to discover alternative theoretical possibilities and that the problem of unconceived alternatives therefore poses a less significant threat to contemporary scientific communities than it did to their historical predecessors. I first argue that the most profound and fundamental historical transformations of the scientific enterprise have actually increased rather than decreased our vulnerability to the problem. I then argue that whether we are troubled by even the prospect of increasing theoretical conservatism in science should depend on the position we occupy in the ongoing debate concerning scientific realism itself.

Political science research, particularly in international relations and comparative politics, has increasingly become dominated by statistical and formal approaches. The promise of these approaches shifted the methodological emphasis away from case study research. In response, supporters of case study research argue that case studies provide evidence for causal claims that is not available through statistical and formal research methods, and many have advocated multimethod research. I propose a way of understanding the integration of multiple methodologies in which the causes sought in case studies are treated as singular causation and contingent on a theoretical framework.

I offer an explanation of why inertial and gravitational mass are equal in Newtonian gravitation. I then argue that this is an example of a kind of explanation that is not captured by standard philosophical accounts of scientific explanation. Moreover, this form of explanation is particularly important, at least in physics, because demands for this kind of explanation are used to motivate and shape research into the next generation of physical theories. I suggest that explanations of the sort I describe reveal something important about one way in which physical theories may be related diachronically.

I consider the problem of extending Reichenbach's principle of the common cause to more than two events, vis-à-vis an example posed by Bernstein. It is argued that the only reasonable extension of Reichenbach's principle stands in conflict with a recent proposal due to Horwich. I also discuss prospects of the principle of the common cause in the light of these and other difficulties known in the literature and argue that a more viable version of the principle is the one provided by Penrose and Percival (1962).

In a recent issue of this journal, M. Frisch claims to have proven that classical electrodynamics is an inconsistent physical theory. We argue that he has applied classical electrodynamics inconsistently. Frisch also claims that all other classical theories of electromagnetic phenomena, when consistent and in some sense an approximation of classical electrodynamics, are haunted by “serious conceptual problems” that defy resolution. We argue that this claim is based on a partisan if not misleading presentation of theoretical research in classical electrodynamics.

In this paper we examine the pattern of conceptual change during scientific revolutions by using methods from cognitive psychology. We show that the changes characteristic of scientific revolutions, especially taxonomic changes, can occur in a continuous manner. Using the frame model of concept representation to capture structural relations within concepts and the direct links between concept and taxonomy, we develop an account of conceptual change in science that more adequately reflects the current understanding that episodes like the Copernican revolution are not always abrupt. When concepts are represented by frames, the transformation from one taxonomy to another can be achieved in a piecemeal fashion not preconditioned by a crisis stage, and a new taxonomy can arise naturally out of the old frame instead of emerging separately from the existing conceptual system. This cognitive mechanism of continuous change demonstrates the constructive roles of anomaly and incommensurability in promoting the progress of science.

In seeking general accounts of evidence, confirmation, or inference, philosophers have looked to logical relationships between evidence and hypotheses. Such logics of evidential relationship, whether hypothetico-deductive, Bayesian, or instantiationist fail to capture or be relevant to scientific practice. They require information that scientists do not generally have (e.g., an exhaustive set of hypotheses), while lacking slots within which to include considerations to which scientists regularly appeal (e.g., error probabilities). Building on my co-symposiasts contributions, I suggest some directions in which a new and more adequate philosophy of evidence can move.

Recent years have seen increased interest in the question of whether it is possible to provide an evolutionary game-theoretic explanation for certain kinds of social norms. I sketch a proof of a general representation theorem for a large class of evolutionary game-theoretic models played on a social network, in hope that this will contribute to a greater understanding of the long-term evolutionary dynamics of such models, and hence the evolution of social norms.

Callender and Cohen argue that there is no need for a special account of the constitution of scientific representation. I argue that scientific representation is communal and therefore deeply tied to the practice in which it is embedded. The communal nature is accounted for by licensing, the activities of scientific practice by which scientists establish a representation. A case study of the Lotka-Volterra model reveals how licensure is a constitutive element of the representational relationship. Thus, any account of the constitution of scientific representation must account for licensing, meaning that there is a special problem of scientific representation.

There is currently a consensus among comparative psychologists that nonhuman animals are capable of some forms of mindreading. Several philosophers and psychologists have criticized this consensus, however, arguing that there is a “logical problem” with the experimental approach used to test for mindreading in nonhuman animals. I argue that the logical problem is no more than a version of the general skeptical problem known as the theoretician’s dilemma. As such, it is not a problem that comparative psychologists must solve before providing evidence for mindreading.

We argue that ‘locality’, perhaps the most mundane term in ecology, holds a basic ambiguity: two concepts of space—nomothetic and idiographic—which are both necessary for a rigorous resurvey to “the same” locality in the field, are committed to different practices with no common measurement. A case study unfolds the failure of the standard assumption that an exogenous grid of longitude and latitude, as fine-grained as one wishes, suffices for revisiting a species locality. We briefly suggest a scale-dependent “resolution” for this replication problem, since it has no general, rational solution.