Abstract
Several forms of naturalism are currently extant. Proponents of the various approaches disagree on matters of strategy and detail but one theme is common: we have not received any revelations about the nature of the world -- including our own nature. Whatever knowledge we have has been acquired through a fallible process of conjecture and revision. This common theme will bring to mind the writings of Karl Popper and, in many respects, Popper is the father of contemporary naturalism. Along with Popper, the form of naturalism that I would defend is realistic in the following sense: it considers the acquisition of knowledge of the nature of the world to be a pursuable long-term goal of our epistemic activities. (See Brown [1987, 1988, 1990].) Popper's central interest in truth has led him to object to the pervasive concern with concepts among contemporary philosophers. Truth, Popper insists, is the fundamental epistemic concern; propositions are the bearers of truth; and the evaluation of propositions should be at the center of our epistemic focus (e.g., 1965, pp. 18-21; 1972, pp. 123-24). Concern with concepts, Popper maintains, is a distraction. Yet, this leaves us in an odd position. When we study a particular subject matter, one of our main problems is to determine what kinds of entities and processes occur in that domain. But the kinds of entities and processes we attribute to a domain will be captured in the concepts we use for describing that domain and, from a naturalistic point of view, concepts are no more available through revelation than are propositions. As our knowledge develops, we must not only propose and evaluate propositions, we must also propose and evaluate concepts