Paradigms and Incommensurability

Abstract

One of the consequences of the new image of science has been an emphasis on the ‘incommensurability’ of paradigms. As we have seen, advocates of the new image challenge the view that statements, including scientific theories, have some atomic, fixed meanings; they argue that statements have meanings only by virtue of their relations to other statements in the system to which they belong. Further, Kuhn and Feyerabend stress the very impossibility of comparing, contrasting and discussing different observational languages, theories and standards when different scientific paradigms are involved. Scientists work within these paradigms, and the paradigms determine the scientists’ views of the world. A scientist working within a given paradigm simply cannot, on Kuhn’s account, transcend his own particular situation. In his words: ‘Though most of the same signs are used before and after a [scientific] revolution e.g. force, mass, element, compound, cell the ways in which some of them attach to nature have changed. Successive theories are thus, we say, incommensurable.’¹ Feyerabend is in general agreement with Kuhn, acknowledging that ‘succeeding paradigms can be evaluated only with difficulty and that they may be altogether incomparable’.² He goes on to speak of incommensurable theories whose ‘content cannot be compared’.