I call an experiment “crucial” when it makes possible a decisive choice between conflicting hypotheses. Joharmsen's selection for size and weight within pure lines of beans played a central role in the controversy over continuity or discontinuity in hereditary change, often known as the Biometrician-Mendelian controversy. The “crucial” effect of this experiment was not an instantaneous event, but an extended process of repeating similar experiments and discussing possible objections. It took years before Johannsen's claim about the genetic stability of pure (...) lines was accepted as conclusively demonstrated by the community of geneticists. The paper also argues that crucial experiments thus interpreted contradict certain ideas about the underdetermination of theories by facts and the theory-ladenness of facts which have been influential in recent history and sociology of science. The acceptance of stability in the pure lines did not rest on prior preference for continuity or discontinuity. And this fact permitted a final choice between the two theories. When such choice is characterized as “decisive” or “final”, this is not meant in an absolute philosophical sense. What we achive in these cases is highly reliable empirical knowledge. The philosophical possibility of drawing (almost) any conclusion in doubt should be distinguished from reasonable doubt in empirical science. (shrink)

Summary In 1979, Robert C. Olby published an article titled ?Mendel no Mendelian??, in which he questioned commonly held views that Gregor Mendel (1822?1884) laid the foundations for modern genetics. According to Olby, and other historians of science who have since followed him, Mendel worked within the tradition of so-called hybridists, who were interested in the evolutionary role of hybrids rather than in laws of inheritance. We propose instead to view the hybridist tradition as an experimental programme characterized by a (...) dynamic development that inadvertently led to a focus on the inheritance of individual traits. Through a careful analysis of publications on hybridization by Carl Linnaeus (1707?1778), Joseph Gottlieb Koelreuter (1733?1806), Carl Friedrich Gärtner (1772?1850), and finally Mendel himself, we will show that this development consisted in repeated reclassifications of hybrids to accommodate anomalies, which in the end allowed Mendel to draw analogies between whole organisms, individual traits, and ?elements? contained in reproductive cells. Mendel's achievement was a product of normal science, and yet a revolutionary step forward. This also explains why, in 1900, when the report he gave on his experiments was ?rediscovered?, Mendel could be read as a ?Mendelian? (shrink)

It is evident how much Olby and Provine have contributed to a better understanding of the emergence of genetics. It is equally evident, I believe, how many obscure issues still remain to be elucidated. Indeed, their volumes have raised as many new questions as they have answered old ones. In particular, the role of constructive as well as retarding contemporary concepts in the development of new generalizations still requires far more analysis. The somewhat independent trends of various national schools and (...) the influence of neighboring fields (e.g. statistics, animal husbandry, systematics) are other areas deserving further study. All these influences contributed, one way or another, to the growth and maturation of genetics.37. (shrink)

Two books have been particularly influential in contemporary philosophy of science: Karl R. Popper's Logic of Scientific Discovery, and Thomas S. Kuhn's Structure of Scientific Revolutions. Both agree upon the importance of revolutions in science, but differ about the role of criticism in science's revolutionary growth. This volume arose out of a symposium on Kuhn's work, with Popper in the chair, at an international colloquium held in London in 1965. The book begins with Kuhn's statement of his position followed by (...) seven essays offering criticism and analysis, and finally by Kuhn's reply. The book will interest senior undergraduates and graduate students of the philosophy and history of science, as well as professional philosophers, philosophically inclined scientists, and some psychologists and sociologists. (shrink)

Genesis: The Evolution of Biology presents a history of the past two centuries of biology, suitable for use in courses, but of interest more broadly to evolutionary biologists, geneticists, and biomedical scientists, as well as general readers interested in the history of science. The book covers the early evolutionary biologists-Lamarck, Cuvier, Darwin and Wallace through Mayr and the neodarwinian synthesis, in much the same way as other histories of evolution have done, bringing in also the social implications, the struggles with (...) our religious understanding, and the interweaving of genetics into evolutionary theory. What is novel about Sapp's account is a real integration of the cytological tradition, from Schwann, Boveri, and the other early cell biologists and embryologists, and the coverage of symbiosis, microbial evolutionary phylogenies, and the new understanding of the diversification of life coming from comparative analyses of complete microbial genomes. The book is a history of theories about evolution, genes and organisms from Lamarck and Darwin to the present day. This is the first book on the general history of evolutionary biology to include the history of research and theories about symbiosis in evolution, and first to include research on microbial evolution which were excluded from the classical neo-Darwinian synthesis. Bacterial evolution, and symbiosis in evolution are also excluded from virtually every book on the history of biology. (shrink)