Several evolutionary biologists have used a parsimony argument to argue that the single gene is the unit of selection. Since all evolution by natural selection can be represented in terms of selection coefficients attaching to single genes, it is, they say, “more parsimonious” to think that all selection is selection for or against single genes. We examine the limitations of this genic point of view, and then relate our criticisms to a broader view of the role of causal concepts and the dangers of reification in science.

Popper distinguishes the problems of theoretical and pragmatic preference between rival theories, but he claims that there is a common non-inductive solution to both of them, viz. the “best-tested theory”, or the theory with the highest degree of corroboration. He further suggests that the degrees of corroboration serve as indicators of verisimilitude. One may therefore raise the question whether the recent theory of verisimilitude gives a general non-inductive solution to the problem of theoretical preference. This paper argues that this is not the case: the theory of verisimilitude is applicable to this problem if and only if there is an independent solution to the problem of induction. Moreover, the solutions to the theoretical and pragmatic problems of preference coincide only in some special cases.

Although on opposite sides of the logic of discovery debate, Laudan and Simon share a thesis of divorce between discovery (invention) and justification (appraisal); but unlike some other authors, they do not base their respective versions of the divorce-thesis on the empirical/logical distinction. Laudan argues that, in contemporary science, invention is irrelevant to appraisal, and that this irrelevance renders epistemically pointless the inventionist program. Simon uses his divorce-thesis to defend his account of invention, which he claims to be non-inductive—so evading the problem of induction. Underlying both authors' positions are inadequate conceptions of inductive inference. Laudan here ignores the role in contemporary science of plausibility arguments, which provide a crucial link between invention and appraisal, and thence an epistemic rationale for inventionism. Simon's account of invention does covertly call upon inductive principles from the context of appraisal, and this is what gives his program epistemic import; otherwise he would be vulnerable to Laudan's “no rationale” critique. The tensions in both authors reveal the falsity of the divorce-thesis, and the essential function of induction in both appraisal and invention of hypotheses.

Wilfrid Sellars has proposed a materialist account of sensation which relies in part on the postulation of special kinds of individuals. This postulational strategy appears to be analogous to the one that introduces such entities as electrons. After setting out Sellars' account, I focus on his application of the postulational strategy. I argue that this application requires the discovery of new effects for familiar properties; that this kind of discovery is disanalogous to what postulation usually does; and that this kind of discovery cannot really be arrived at by postulation. I conclude that Sellars has not provided a successful, materialist account of sensation.

Aristotle's rule of proportions of the factors of motion, presented in VII 5 of the Physics, characterizes Aristotelian force. Observing that the locomotion to which Aristotle applied the Rule is the motion produced by manual labor, I develop an interpretation of the factors of motion that reveals that Aristotelian force is Newtonian power. An alternate interpretation of the Rule by Toulmin and Goodfield implicitly identifies Aristotelian force with Newtonian force. In order to account for the absence of an acceleration in the rate of forced motion, they incorporate into the Rule the medium's resistance to motion due to viscosity as an additional factor. The resulting interpretations of the original factors of motion lose the exactness the power interpretation grants them. The constant rate of forced motion follows immediately from the power interpretation. It is also compatible with the Rule's description of the motion that is produced by the sum of forces.

The conventionalist epistemology of cultural anthropology can be seen to be embedded in the methods of ‘cognitive anthropology’, the study of folk conceptual systems. These methods result in indiscriminately depicting all folk systems as conventional, whether or not the systems are intended by the native to represent objective features of the world. Hypothetical and actual ethnographic situations are discussed. It is concluded that the anthropologist's projection of his/her own epistemology onto a native system is ethnocentric. This epistemological prejudice may be peculiar to the cognitive sciences.

It is shown by means of a simple example that a good explanation of an event is not necessarily corroborated by the occurrence of that event. It is also shown that this contention follows symbolically if an explanation having higher “explicativity” than another is regarded as better.

Some recent physiological data indicate that the “subjective timing” of experiences can be “automatically referred backwards in time” to represent a sequence of events even though the earlier portions of associated neurophysiological activity are themselves insufficient to elicit the experience of any sensation. The challenge, then, is to explain how subjects can experience what they do in the reported ways when, if one looked just at certain neurophysiological activity, it would seem that perhaps subjects should report their sensations differently. The phenomenon has seemed sufficiently remarkable to the neurobiologist John Eccles to count as evidence for mind-body dualism (Eccles 1977). This dualistic interpretation has resulted in a spirited attack by P. S. Churchland on both the physiological research and the dualistic interpretation (Churchland 1981a). Her attack resulted in an equally spirited defense of the research by the primary investigator, B. Libet, where he reaffirmed his more guarded interpretation that “the temporal discrepancy creates relative difficulties for identity theory, but that these are not insurmountable” (Libet 1981, p. 196). In turn, Churchland has defended her criticism of Libet's research so that, for her, Libet's hypothesis remains “infirm and unconfirmed” (Churchland 1981b, p. 496).

In a recent article (1980) G. H. Merrill has defended realism against an argument devised by Hilary Putnam. My first aim is to show that Merrill's defence is inadequate. I shall also argue that the proper conclusion of Putnam's argument is somewhat different from the conclusion Putnam himself offers.

In the insightful and searching paper of Mills and Beatty (1979) the following definition of ‘fitness’, as the term figures in the theory of natural selection, is offered:

The [individual] fitness of an organism x in environment E equals n =dfn is the expected number of descendants which x will leave in E.

One of the things I attempted to do in my paper on independent testability (1980) was to illustrate convincingly the very real difficulties of distinguishing between the accidental and essential features of a scientific experiment. The importance of this distinction is that independent testability presumably requires differences that are essential and telling and not merely accidental reflections of existing experimental technique or of the procedural preferences of the experimenter. In the case of the Michelson-Morley (MM) and Kennedy-Thorndike (KT) experiments, I showed, following a suggestion of M. G. Evans, that Grünbaum's attempt to distinguish these two experiments does not work. I also showed that certain obvious and natural variations of Grünbaum's approach do not adequately distinguish these experiments. So, for example, it will not do simply to claim that MM is characterized by equal arms and KT by unequal arms, since equal arms are required for MM only in the absence of adequate photographic registration methods. But if these methods are not available then KT is not possible. Conversely, if these methods are available, then while both MM and KT are experimentally possible, MM need not be restricted to equal arms.

Frankel (1976) has argued that the theory of causality developed by Rom Harré (Harré 1970) and his colleague Edward Madden (Harré and Madden 1975) is incoherent, since the proposal that causal claims are naturally necessary leads to a vicious infinite regression

“which ends by requiring that for any causal claim to be accorded the status of natural necessity an infinite number of causal claims must be accorded the status of natural necessities.” (Frankel 1976, p. 560)