Traditionally, species have been treated as classes. In fact they may be considered individuals. The logical term “individual” has been confused with a biological synonym for “organism.” If species are individuals, then: 1) their names are proper, 2) there cannot be instances of them, 3) they do not have defining properties, 4) their constituent organisms are parts, not members. “ Species " may be defined as the most extensive units in the natural economy such that reproductive competition occurs among their (...) parts. Species are to evolutionary theory as firms are to economic theory: this analogy resolves many issues, such as the problems of “reality” and the ontological status of nomenclatorial types. (shrink)

Twentieth century philosophy of science has been dominated by a view of language with a strong prejudice against psychology, even while empirical psychology has moved away from the nineteenth century philosophical psychology against which the prejudice was originally directed. This legacy is shown to dominate even in recent Kripke‐inspired efforts toward new theories of meaning. Its influence is argued to undermine prospects for making sense of such phenomena as scientific progress. Avoiding this consequence requires that we pursue a psychologically informed (...) theory of meaning. (shrink)

UNCLEAR as it is, the traditional doctrine that the notion "meaning" possesses the extension/intension ambiguity has certain typical consequences. The doctrine that the meaning of a term is a concept carried the implication that mean- ings are mental entities. Frege, however, rebelled against this "psy- chologism." Feeling that meanings are public property-that the same meaning can be "grasped" by more than one person and by persons at different times-he identified concepts (and hence "intensions" or meanings) with abstract entities rather than (...) mental entities. However, "grasping" these abstract entities was still an individual psychological act. None of these philosophers doubted that understanding a word (knowing its intension) was just a matter of being in a certain psychological state (somewhat in the way in which knowing how to factor numbers in one's head is just a mat- ter of being in a certain very complex psychological state). (shrink)

_This sweeping discussion of the philosophy of evolutionary biology is based on the revolutionary idea that species are not kinds of organisms but wholes composed of organisms._.

The present edition provides a detailed and accessible discussion ofhis theories and adds an account of the immediate responses to the book on publication.

Ever since Charles Darwin's On the Origin of Species was published, the received view has been that Darwin literally thought of species as not extra-mentally real. In 1969 Michael Ghiselin upset the received view by interpreting Darwin to mean that species taxa are indeed real but not the species category. In 1985 John Beatty took Ghiselin's thesis a step further by providing a strategy theory to explain why Darwin would say one thing (his repeated nominalistic definition of species) and do (...) another (hold that species taxa are real). In the present paper I attempt to take this line of interpretation to a new level. Guided by the principle of charity, I provide and analyze a considerable amount of evidence from Darwin's mature writings (both private and published) to show that (contra Ghiselin and Beatty) Darwin did not simply accept the species delimitations of his fellow naturalists but actually employed, repeatedly and consistently, a species concept in a thoroughly modern sense, albeit with an implicit definition, a concept uniquely his own and fully in accord with his theory of evolution by natural selection. This implicit concept and definition is carefully reconstructed in the present paper. A new strategy theory is then provided to account for why Darwin would define species (both taxa and category) nominalistically on the one hand but delimit species realistically on the other. (shrink)

Philosophers have distinguished a metaphysical category which they term "historical entities" or "continuants". Such particulars are spatiotemporally localized and develop continuously through time while retaining internal cohesiveness. Species, social groups and conceptual systems can be profitably treated as historical entities. No damage is done to preanalytic intuitions in treating social groups as historical entities; both biological species and conceptual systems can be construed as historical entities only by modifying the ordinary way of viewing both. However, if species and conceptual systems (...) are to "evolve", then they must be treated as historical entities. The type specimen method, which is used by systematists to individuate and name biological taxa, is set out and then extended to apply to scientific communities as social groups and conceptual systems. (shrink)