This paper examines the "causal theory of reference", according to which science aims at the discovery of "essences" which are the objects of reference of natural kind terms (among others). This theory has been advanced as an alternative to traditional views of "meaning", on which a number of philosophical accounts of science have relied, and which have been criticized earlier by the present author. However, this newer theory of reference is shown to be equally subject to fatal internal difficulties, and (...) to be incompatible with actual science as well. Indeed, it rests on assumptions which it shares with the purportedly opposing theory of meaning. Behind those common assumptions is the supposition that the nature of science can be illuminated by an examination of alleged necessities of language which are independent of the results and methods of scientific inquiry. An alternative view of science is proposed, according to which the goals and language of science develop as integral parts of the process of demarcating science from non-science, a process in which the notion of a "reason" gradually assumes a decisive role. On this view, the comparability, competition, and development of scientific ideas are understood without reliance on either common "meanings" or common "references" as fundamental tools of analysis. (shrink)