Single Idea 9680

[catalogued under 4. Formal Logic / F. Set Theory ST / 2. Mechanics of Set Theory / c. Basic theorems of ST]

Full Idea

The empty set Φ is a subset of every set (including itself).

Gist of Idea

The empty set Φ is a subset of every set (including itself)

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

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