more from David Wiggins

### Single Idea 11831

#### [catalogued under 9. Objects / F. Identity among Objects / 2. Defining Identity]

Full Idea

The formal properties of identity are the reflexivity of identity, and Leibniz's Law (if x is the same as y, then whatever is true of one is true of the other).

Gist of Idea

The formal properties of identity are reflexivity and Leibniz's Law

Source

David Wiggins (Sameness and Substance Renewed [2001], Pr.2)

Book Reference

Wiggins,David: 'Sameness and Substance Renewed' [CUP 2001], p.4

A Reaction

Presumably transitivity will also apply, and, indeed, symmetry. He seems to mean something like the 'axiomatic formal properties'.

Related Idea

Idea 16017
Identity is usually defined as the equivalence relation satisfying Leibniz's Law **[Noonan]**