<ontology, metaphysics, accident, existentialism> distinction among the attributes, properties, or qualities of substances. A thing's possession of its essential properties is necessary either for its individual existence or, at least, for its membership in a specific kind. Accidental features, by contrast, are those which the thing merely happens to have, even though it need not. Thus, for example, rationality may be part of the essence of any human being, but being able to calculate square roots accurately in one's head is (surely) an accident. The legitimacy of the distinction itself is called into question by philosophers ("anti-essentialists") who doubt whether any features are genuinely essential to the things that have them. Recommended Reading: Charlotte Witt, Substance and Essence in Aristotle: An Interpretation of Metaphysics vii-ix (Cornell, 1994); Saul A. Kripke, Naming and Necessity (Harvard, 1982); and Garth L. Hallett, Essentialism: A Wittgensteinian Critique (SUNY, 1991).
[A Dictionary of Philosophical Terms and Names]
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