Abstract
analogy, the similarity along with difference, among meanings, among sorts of thinking, and among realities. Analogy theory originated with *Aristotle in its three main parts: analogy of meaning, analogous thinking, and analogy of being. There were some antecedents in *Plato, where the names of Forms and of participating things are the same but differ in meaning, and the notion of ‘being’ is said to differ with what we are talking about, for example Forms versus physical things (Sophist). Systematic use of the three elements to unify philosophy and to resolve problems is, however, Aristotle's invention along with the idea that *metaphor is a species of analogy. Aristotle distinguished what were later called analogies of attribution, based on causation, signs, symptoms, and representations (medical skill, medical supplies; hat/head cover, hat/in picture), from analogy based on proportionality, A: B :: C : D; where the common implicit predicate is related in meaning (supplied food.