According to a widespread view, Thomas Kuhn’s model of scientific development would relegate rationality to a second plane, openly flirting with irrationalist positions. The intent of this article is to clarify this aspect of his thinking and refute this common interpretation. I begin by analysing the nature of values in Kuhn’s model and how they are connected to rationality. For Kuhn, a theory is chosen rationally when: i) the evaluation is based on values characteristic of science; ii) a theory is (...) considered better the more it manifests these values; and iii) the scientist chooses the best-evaluated theory. The second part of this article deals with the thesis of the variability of values. According to Kuhn, the examples through which epistemic values are presented vary for each person, and for this reason individuals interpret these criteria differently. Consequently, two scientists, using the same values, can come to a rational disagreement over which theory to choose. Finally, I point out the limitations of this notion of rationality for the explanation of consensus formation, and the corresponding demand for a sociological theory that reconnects individual rationality with convergence of opinions. (shrink)

The Structure of Scientific Revolutions represented a milestone in the attempt to understand scientific development based on empirical observations. However, in the next decades after the publication of his book, history, psychology, and sociology became increasingly marginal in Kuhn’s discussions. In his last articles, Kuhn even suggested that philosophers should pay less attention to empirical data and focus more on “first principles.” The purpose of this article is, first, to describe this radical transformation in Kuhn’s methodological approach, from his initial (...) naturalism to his later and more strict philosophical stance. Next, I present some of the alleged justifications for explaining this transition, such as his interest in problems more firmly attached to the philosophical tradition and a desire for greater acceptance within this community. Although these factors certainly played a role in explaining Kuhn’s change, I also believe that an important theoretical component exerts a fundamental function in this transition: the idea that scientific development is a kind of evolutionary process, which is better understood through the use of abstract theoretical models, instead of sparse observations of scientific activity. (shrink)

The aim of the article is to explore Thomas Kuhn’s notion of “scientific crisis” and indicate some difficulties with it. First, Kuhn defines “crisis” through the notion of “anomaly” but distinguishes these concepts in two different ways: categorically and quantitatively. Both of these alternatives face considerable problems. The categorical definition relies on a distinction between “discoveries” and “inventions” that, as Kuhn himself admits, is artificial. The quantitative definition states that crises are a deeper, more profound type of anomaly. Kuhn, however, (...) does not offer any criteria for objectively defining this “severity” of the crises. The second kind of problem is related to the application of the concept of “crisis.” Apparently, Kuhn attributes crises to individuals as much as to communities. Lastly, there is the problem of the function of crises. In The Structure of Scientific Revolutions, they are presented as a precondition to scientific revolutions. In later articles, however, Kuhn seems to see them only as a common antecedent to revolutions. (shrink)