more from Graham Priest

### Single Idea 9679

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

Full Idea

X⊂Y means set X is a 'proper subset' of set Y (if and only if all of its members are members of Y, but some things in Y are not in X)

Gist of Idea

X⊂Y means set X is a 'proper subset' of set Y

Source

Graham Priest (Intro to Non-Classical Logic (1st ed) [2001], 0.1.6)

Book Reference

Priest,Graham: 'Introduction to Non-Classical Logic' [CUP 2001], p.-6