Nominalism

Classification

Position level

specific

Domains

Metaphysics

Overview

Only particular things exist; universals are not real entities in the world but signs applied to many similar particulars. Earlier nominalists located that generality in words; Ockham located it in concepts, natural signs in the mind, which is why his version is sometimes called conceptualism. His main case against real universals is that one thing present in many separate things leads to contradictions (Summa Logicae I.15–16). Parsimony adds weight, in his own wording: plurality is not to be posited without necessity. The slogan "entities must not be multiplied beyond necessity" is a later formulation, not his.

Position on

• The Problem of Universals

Held by traditions

• Medieval Nominalism

  Question scope: The Problem of Universals

Rival positions

• Platonic Realism

  Question scope: The Problem of Universals

• Moderate Realism

  Question scope: The Problem of Universals

References

• William of Ockham, Summa Logicae I.15 (universals as concepts, not things)
• Stanford Encyclopedia of Philosophy, William of Ockham (nominalism; the razor in Ockham's own formulations)
• Plato, Phaedo 74a–77a and 100c–e (the Equal itself and participation); Republic V, 475e–480a