This article records tradition as it has been passed down and reported. Its sources are not yet part of the atlas's verified catalogue.
Identity gathers six positions on what makes a thing, or a person, the same thing over time or across its properties, ranging from ancient debates over universals to modern accounts of personal survival.
Essentialism holds that a thing has a core set of properties it must possess to be the kind of thing it is, a claim Aristotle grounded in definition and that most doctrines of a fixed human or divine nature depend on. Nominalism denies that general categories are anything more than names applied to particular things, the position William of Ockham defended against unnecessary multiplication of entities, while Universals As Real holds the opposite, that properties like redness are genuinely shared, wholly and identically, by many particular things, in versions running from Plato's separate realm of Forms to Aristotle's more moderate account of universals existing only within things.
Personal Identity As Continuity, following John Locke, holds that what makes someone the same person over time is an unbroken chain of memory rather than a persisting soul, a view Derek Parfit later pushed further by arguing psychological continuity might matter more than personal identity itself. Personal Identity As Substance holds the reverse, that identity requires an enduring soul or self whether or not memory connects its states, the assumption behind Descartes's dualism and Thomas Reid's direct objection to Locke.
Anatta, the Buddhist teaching of no-self, denies any of these a fixed foundation, holding that what is called a self is only a changing bundle of five aggregates with no permanent owner behind them, directly determining what Buddhist teaching holds is reborn.