Single Idea 10697

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

Full Idea

Indispensable to cross-reference, lacking distinctive content, and pervading thought and discourse, 'identity' is without question a logical concept. Adding it to predicate calculus significantly increases the number and variety of inferences possible.

Gist of Idea

Identity is clearly a logical concept, and greatly enhances predicate calculus

Source

George Boolos (To be is to be the value of a variable.. [1984], p.54)

Book Reference

Boolos,George: 'Logic, Logic and Logic' [Harvard 1999], p.54


A Reaction

It is not at all clear to me that identity is a logical concept. Is 'existence' a logical concept? It seems to fit all of Boolos's criteria? I say that all he really means is that it is basic to thought, but I'm not sure it drives the reasoning process.