<ontology> instantiation in reality, or actual being. Kant pointed out that existence is not a predicate, and Frege proposed that it is a second-order property of those first-order properties that happen to be instantiated. The metaphysical question of what kinds of things exist is the subject of ontology, as is the even more general question of why there is something rather than nothing. Recommended Reading: Colin McGinn, Logical Properties: Identity, Existence, Predication, Necessity, Truth (Clarendon, 2001); Jean-Paul Sartre, Truth and Existence, tr. by Adrian Van Den Hoven and Ronald Aronson (Chicago, 1995); and Emmanuel Levinas, Existence and Existents, tr. by Robert Bernaeconi (Duquesne, 2001).
[A Dictionary of Philosophical Terms and Names]
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