The advance of science and scientific revolutions

Abstract

Scientific revolutions in biology do not conform to the description of such revolutions as given by T. Kuhn. Instead, several paradigms may coexist simultaneously for long periods of time, and succeeding paradigms are not necessarily incommensurable. Biological revolutions are not separated by long periods of normal science; rather, there are always minor revolutions and theory changes of various magnitude. Kuhn's theory is in good agreement with essentialistic philosophy, while theory change in biology fits Darwinian evolutionary epistemology, consisting of variation (the continuing proposal of new theories) and selection (the survival of the successful ones). Nowadays there is very little dissent (at least among scientists) from the thesis that science makes steady advances and that, as a result of these advances, we are gaining an ever improving understanding of the world. What is, however, highly controversial is how these advances occur. This controversy occupies a large portion of the literature of contemporary philosophy of science. Leaving a number of minor movements aside, one can distinguish two major schools, Kuhn's theory of scientific revolutions (and normal science) and Darwinian evolutionary epistemology. I shall not discuss the latter1.