Mayr has made both conceptual and professional contributions to the establishment of the history and philosophy of biology. His conceptual contributions include, among many others, the notion of population thinking. He has also played an important role in the establishment of history and philosophy of biology as viable professional disciplines.

Biological species have been treated traditionally as spatiotemporally unrestricted classes. If they are to perform the function which they do in the evolutionary process, they must be spatiotemporally localized individuals, historical entities. Reinterpreting biological species as historical entities solves several important anomalies in biology, in philosophy of biology, and within philosophy itself. It also has important implications for any attempt to present an "evolutionary" analysis of science and for sciences such as anthropology which are devoted to the study of single (...) species. (shrink)

In 1937, just as Dobzhansky published the book that later generations would laud as the foundation of the modern synthesis, the American Naturnlist published a symposium on "supraspecific variation in nature and in classification." Alfred C. Kinsey, who later became one of America's most controversial intellectuals for his study of basic behaviors in another sort of WASP,1 led off the symposium with a summary of his extensive work on a family of gall wasps, the Cynipidae. In his article, Kinsey strongly (...) advocated the central theme of the developing synthesis: Evolution at all scales, particularly macroevolution, could be explained by the genetic mechanisms observed in laboratories and local populations. He first complained that some geneticists and naturalists were still impeding a synthesis with their insistence upon causal separation of levels: "Just as some of the geneticists have insisted that the laboratory genetics may explain the nature and origin of Mendelian races, but not of natural species, so others indicate that the qualities of higher categories must be explained on bases other than those involved in species" (1937, p. 208). He then defended the central postulate. (shrink)

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)

Ernst Mayr has argued that Darwinian theory discredited essentialist modes of thought and replaced them with what he has called "population thinking". In this paper, I characterize essentialism as embodying a certain conception of how variation in nature is to be explained, and show how this conception was undermined by evolutionary theory. The Darwinian doctrine of evolutionary gradualism makes it impossible to say exactly where one species ends and another begins; such line-drawing problems are often taken to be the decisive (...) reason for thinking that essentialism is untenable. However, according to the view of essentialism I suggest, this familiar objection is not fatal to essentialism. It is rather the essentialist's use of what I call the natural state model for explaining variation which clashes with evolutionary theory. This model implemented the essentialist's requirement that properties of populations be defined in terms of properties of member organisms. Requiring such constituent definitions is reductionistic in spirit; additionally, evolutionary theory shows that such definitions are not available, and, moreover, that they are not needed to legitimize population-level concepts. Population thinking involves the thesis that population concepts may be legitimized by showing their connections with each other, even when they are not reducible to concepts applying at lower levels of organization. In the paper, I develop these points by describing Aristotle's ideas on the origins of biological variation; they are a classic formulation of the natural state model. I also describe how the development of statistical ideas in the 19th century involved an abandoning of the natural state model. (shrink)

The normal and the pathological are terms used for structures, activities, individual or collective situations proper to living beings and especially to man. The relation of a fact and a norm is its positive or negative value. Can the assessment of behaviours be reduced to noting a necessity? Is a living being's disease a fact similar to universal attraction? The author maintains that diseases are not merely predetermined effects, but are revealing of a normative regulation proper to living beings and (...) man. (shrink)

The classical/balance controversy continued along these lines throughout the first half of the sixties. Then, at about the same time that the classical position lost its leading advocate, the balance position received striking new support from Harry Harris, and independently from Dobzhansky's former student Lewontin, and Lewontin's research partner, Jack Hubby.80 These developments served more to reorient the controversy than to end it — and the resulting “neoclassical”/balance controversy is different enough to be grist for another mill.Social policy considerations no (...) longer play a role in keeping the dispute alive. This particular respect in which the issues have changed is, as Diane Paul suggests in her contribution to this volume, as striking as any other.82 There is, however, little danger of our forgetting that this was once much more than just a narrowly technical controversy — the additional social policy issues were far too blatant.However, although blatant, they were by no means the only, or even the most important, issues. In choosing to concentrate on the social policy considerations, I do not mean to suggest that the empirical issues were irrelevant, or simple and straightforward, or otherwise uninteresting. That is by no means the case. What I have tried to show is that there was much more to the classical/balance stalemate than just the empirical underdetermination of the theoretical issues, and that the empirical issues cannot be treated adequately without taking into account the social policy considerations that were involved. Dobzhansky and Muller both appealed to the dangers of misguided social policy that might have resulted from prematurely resolving their controversy in the other's favor. They called for high empirical standards on those grounds, more than once seeking to forestall the resolution of their dispute in this way. (shrink)