Plato's Essentialism. Reinterpreting the Theory of Forms

Abstract

The revival of interest in the concept of essence witnessed in analytic metaphysics over the past half century has customarily been accompanied by the association of the original idea of (and of some of the main lines of thought on) essence with Aristotle. The book under review aims instead to show that Plato already ‘defends a comprehensive, coherent, and well-argued theory of essence’ (p. 11). Politis frames this claim in an overall interpretation of Plato's theory of Forms, governed by a two-pronged principal thesis: (i) Platonic Forms simply are essences, not (as some believe) things that have essences—meaning by ‘essence’ specifically the entity ‘designated by an adequate and true answer to the question. ‘What is F?’ (p. 3), as opposed to an answer that accounts for what F is by merely appealing to an ‘example or exemplar’ of F (ch. 1). (ii) All chief attributes Plato ascribes to Forms follow uniquely from this basic notion, including their being non-perceptible by the senses (ch. 2), unitary, uniform, incomposite, changeless, eternal, and non-logically independent from each other (ch. 3), knowable only by reasoning (ch. 4), distinct and separate from perceptible things (chs. 5 and 9), the basis of causation and explanation (ch. 6), necessary for thought and speech (chs. 7–8).