Proponents of genic selectionism have claimed that evolutionary processes normally viewed as selection on individuals can be “represented” as selection on alleles. This paper discusses the relationship between mathematical questions about the formal requirements upon state spaces necessary for the representation of different types of evolutionary processes and causal questions about the units of selection in such processes.

The critics of “hereditarianism” often claim that any attempt to explain human behavior by invoking genes is confronted with insurmountable methodological difficulties. They reject the idea that heritability estimates could lead to genetic explanations by pointing out that these estimates are strictly valid only for a given population and that they are exposed to the irremovable confounding effects of genotype-environment interaction and genotype-environment correlation. I argue that these difficulties are greatly exaggerated, and that we would be wrong to regard them as presenting a fundamental obstacle to the search for genetic explanations. I also show that, to the extent they are cogent, these objections may prove to be even more damaging to the “environmentalist” standpoint.

When philosophers and psychologists think about consciousness, they generally focus on one or more of three features: phenomenality (how experiences feel), intentionality (that experiences are “of” something, that experiences mean something), and introspectibility (our awareness of the phenomenality and intentionality of experience). Using examples from empirical psychology and neuroscience, I argue that consciousness is not a unitary state, that, instead, these three features characterize different and dissociable states, which often happen to occur together. Understanding these three features as dissociable from each other will resolve philosophical disputes and facilitate scientific investigation.

This essay defends two theses that jointly establish a link between causal and explanatory asymmetry. The first thesis is that statements specifying facts about effects, unlike statements specifying facts about causes, are not “independently variable”. The second thesis is that independent variability among purportedly explanatory factors is a necessary condition on scientific explanations.

I propose an approach to naturalized philosophy of science that takes the social nature of scientific practice seriously. I criticize several prominent naturalistic approaches for adopting “cognitive individualism”, which limits the study of science to an examination of the internal psychological mechanisms of scientists. I argue that this limits the explanatory capacity of these approaches. I then propose a three-level model of the social nature of scientific practice, and use the model to defend the claim that scientific knowledge is socially produced.

A conventional experiment is proposed to resolve the realist/idealist debate by challenging the premise that double blinding and an attitude of objectivity in general deter the corroborative influence which preconceptions exert on perception. The possibility that objectivity enhances corroboration would not contradict empirical findings, and would account for the success of science.

In Gemes (1990) I examined certain formal versions of hypothetico-deductivism (H-D) showing that they have the unacceptable consequence that “Abe is a white raven” confirms “All ravens are black”! In Gemes (1992) I developed a new notion of content that could save H-D from this bizarre consequence. In this paper, I argue that more traditional formulations of H-D also need recourse to this new notion of content. I present a new account of the vexing notion of the natural axiomatization of a theory. The notion is used to construct a form of H-D that allows for the type of selective confirmation without which Glymour (1980a,b) claims H-D is hopeless.

In the context of a discussion of time symmetry in the quantum mechanical measurement process, Aharonov et al. (1964) derived an expression concerning probabilities for the outcomes of measurements conducted on systems which have been pre- and postselected on the basis of both preceding and succeeding measurements. Recent literature has claimed that a resulting “time-symmetrized” interpretation of quantum mechanics has significant implications for some basic issues, such as contextuality and determinateness, in elementary, nonrelativistic quantum mechanics. Bub and Brown (1986) have shown that under the standard interpretation of the aforementioned expression, these claims employ ensembles which are not well defined. It is argued here that under a counterfactual interpretation of the expression, these claims may be understood as employing well-defined ensembles; it is shown, however, that such an interpretation cannot be reconciled with the standard interpretation of quantum mechanics.

R. Laudan and L. Laudan (1989) have put forth a new model intended to solve the problem of disagreement, the problem of consensus, and the problem of innovation in science. In support of this model they cite the history of the acceptance of continental drift, or plate tectonics. In this discussion, I claim that this episode does not constitute an instance of their model. The historical evidence does not support this model. Indeed, closer examination seems to weaken it. I also sketch an alternative model.