Classifying is a fundamental operation in the acquisition of knowledge. Taxonomic theory can help students of cognition, evolutionary psychology, ethology, anatomy, and sociobiology to avoid serious mistakes, both practical and theoretical. More positively, it helps in generating hypotheses useful to a wide range of disciplines. Composite wholes, such as species and societies, are “individuals” in the logical sense, and should not be treated as if they were classes. A group of analogous features is a natural kind, but a group of (...) homologous features is not. Imposing hypotheses justified only on the basis of nominalist, realist, phenomenalist, or conceptualist metaphysics upon the neurophysiology of organisms or upon the causes of behavior exemplifies the “psychologist's fallacy” of William James. Levels should be distinguished from their members and from classes of levels, and the ontological status of entities ranked at levels should be made clear. It is important not to confuse such categories as substance and process with one another. Several genetical terms, such as “gene” and chromosome,” are even more equivocal than has been realized. Discussions about units of selection, behavior, and thinking suffer from the ambiguity of a “unit of” an entity. An important source of misunderstanding about natural selection is the habit of treating it as an “agent”: in an important sense, natural selection does not “act” at all. (shrink)

This article examines the learning of a scientific procedure, and its connection to the greater scientific community through the notion of Wittgensteinian rules. The analysis reveals this connection by demonstrating that learning in interaction is largely grounded in rule-based community descriptions and judgments rather than any inner process. This same analysis also demonstrates that learning processes are particularly suited for such an analysis because rules and concomitant phenomena comprise a significant portion of any learning interaction. This analysis further reveals the (...) elucidating merit of Wittgensteinian rules, their relation to community and the concept of practice, and promotes the efficacy of participant-generated rule-formulations as analytic descriptors. (shrink)