Abstract
Although the relevance and importance of his work has been recognized only belatedly, Charles Sanders Peirce was, throughout his life, a careful student and significant contributor to the development of logic, scientific theory, and philosophy generally. Occasionally, complete appreciation of Peirce's efforts has been hampered because his work is often unique and, at times, highly idiosyncratic. Yet, we hope to show in this paper that for one aspect of his work in logic Peirce did not abandon the ordinary without purpose. Only relatively recently have philosophers of science become interested in the logic of discovery - that is, in the logic of the selection of hypotheses to be tested rather than simply in the ways of testing hypotheses which have already been selected.