The paper discusses concept individuation in the context of scientific concepts and conceptual change in science. It is argued that some concepts can be individuated in different ways. A particular term may be viewed as corresponding to a single concept. But at the same time, we can legitimately individuate in a more fine grained manner, i.e., this term can also be considered as corresponding to two or several concepts. The reason is that there are different philosophical and explanatory interests that (...) underlie a particular study of the change of a scientific term. These interests determine how a concept is to be individuated; and as the same term can be subject to different philosophical studies and interests, its content can be individuated in different ways. (shrink)

Agents can think using concepts they do not fully understand. This paper investigates the question “Under what conditions does a thinker fully understand, or have mastery of, a concept?” I lay out a gauntlet of problems and desiderata with which any theory of concept mastery must cope. I use these considerations to argue against three views of concept mastery, according to which mastery is a matter of holding certain beliefs, being disposed to make certain inferences, or having certain intuitions. None (...) of these attitudes is either necessary or sufficient for mastery. I propose and respond to objections to my own recognition view of the conditions under which a thinker has mastery of a concept. (shrink)

The theory of concepts advanced in the dissertation aims at accounting for a) how a concept makes successful practice possible, and b) how a scientific concept can be subject to rational change in the course of history. Traditional accounts in the philosophy of science have usually studied concepts in terms only of their reference; their concern is to establish a stability of reference in order to address the incommensurability problem. My discussion, in contrast, suggests that each scientific concept consists of (...) three components of content: 1) reference, 2) inferential role, and 3) the epistemic goal pursued with the concept's use. I argue that in the course of history a concept can change in any of these three components, and that change in one component—including change of reference—can be accounted for as being rational relative to other components, in particular a concept's epistemic goal.This semantic framework is applied to two cases from the history of biology: the homology concept as used in 19th and 20th century biology, and the gene concept as used in different parts of the 20th century. The homology case study argues that the advent of Darwinian evolutionary theory, despite introducing a new definition of homology, did not bring about a new homology concept (distinct from the pre-Darwinian concept) in the 19th century. Nowadays, however, distinct homology concepts are used in systematics/evolutionary biology, in evolutionary developmental biology, and in molecular biology. The emergence of these different homology concepts is explained as occurring in a rational fashion. The gene case study argues that conceptual progress occurred with the transition from the classical to the molecular gene concept, despite a change in reference. In the last two decades, change occurred internal to the molecular gene concept, so that nowadays this concept's usage and reference varies from context to context. I argue that this situation emerged rationally and that the current variation in usage and reference is conducive to biological practice.The dissertation uses ideas and methodological tools from the philosophy of mind and language, the philosophy of science, the history of science, and the psychology of concepts. (shrink)