Concept
Extensionality
Overview
In logic, extensionality, or extensional equality, refers to principles that judge objects to be equal if they have the same external properties. It stands in contrast to the concept of intensionality, which is concerned with whether the internal definitions of objects are the same.
Overview adapted from Wikipedia (CC BY-SA 4.0; see the article history for authors).
Related ideas
- Function (mathematics)
- Natural number
- Ordered pair
- Relation (mathematics)
- Set (mathematics)
- Set theory
- Type theory
- Logic
- Axiom of extensionality
- Decidability (logic)
- Equivalence relation
- Extension (predicate logic)
Place in the tradition
Part of Outline of logic.