Single Idea 13851

[catalogued under 5. Theory of Logic / D. Assumptions for Logic / 4. Identity in Logic]

Full Idea

Unlike ∨, →, ↔, and ∀, the sign = is not eliminable from a logic.

Clarification

=

Gist of Idea

Unlike most other signs, = cannot be eliminated

Source

Engelbretsen,G/Sayward,C (Philosophical Logic: Intro to Advanced Topics [2011], Ch.3)

Book Reference

Engelbretsen,G/Sayward,C: 'Philosophical Logic: Intro to Advanced Topics' [Continuum 2011], p.70