Levels

Abstract

The levels metaphor is commonly used to describe science, its theories, and the world. Yet the metaphor means different things in different contexts, inviting equivocation. These distinct applications of the metaphor can be distinguished by the relata they relate, the relation between levels that they assert, and the rule by which they locate items at a level. I discuss these many applications of the levels metaphor with an eye to developing a descriptively adequate account of one particular application: levels of mechanisms. I argue that this application of the metaphor is central to the explanatory practices of the special sciences and defensible as a metaphysical picture of how phenomena studied in the special sciences are constituted.