more from Herbert B. Enderton

Single Idea 9712

[catalogued under 4. Formal Logic / F. Set Theory ST / 2. Mechanics of Set Theory / b. Terminology of ST]

Full Idea

A relation is 'symmetric' on a set if every ordered pair in the set has the relation in both directions.

Gist of Idea

A relation is 'symmetric' on a set if every ordered pair has the relation in both directions

Source

Herbert B. Enderton (A Mathematical Introduction to Logic (2nd) [2001], Ch.0)

Book Reference

Enderton,Herbert B.: 'A Mathematical Introduction to Logic' [Academic Press 2001], p.5