Aristotle and the Problem of Concepts

By a "concept" , I mean a unitary thought (of the sort normally represented by a word) that applies to a plurality of differing objects, and by "The Problem of Concepts" I mean the pervasive philosophical questions of how such thoughts are to be explained and by what standards they are to be evaluated. Aristotle is generally held to have been a Moderate Realist, who held that a concept is a putative grasp of a mind-independent universal object that exist somehow in or derivatively on the many particular objects to which the concept applies. I argue that Aristotle rejected the posit of such universal objects and instead understood universality as a feature of thought, which has a basis in reality and a function in cognition. With some notable exceptions, concepts are based on relations of difference in "the more and the less" between their instances and on the causal relations between the various parts and characteristics of each instance. A concept's function is to serve as a term in deductions which enable us to represent the necessity of causal connections. I go on, then, to explore the manner in which, on Aristotle's view, concepts compose propositions and bodies of knowledge and the way in which they are formed