more from Herbert B. Enderton

### Single Idea 9701

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

Full Idea

A 'relation' is a set of ordered pairs. The ordering relation on the numbers 0-3 is captured by - in fact it is - the set of ordered pairs {<0,1>,<0,2>,<0,3>,<1,2>,<1,3>,<2,3>}.

Gist of Idea

A 'relation' is a set of ordered pairs

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.4

A Reaction

This can't quite be a definition of order among numbers, since it relies on the notion of a 'ordered' pair.