Single Idea 17757

[catalogued under 6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / e. Ordinal numbers]

Full Idea

Every member of an ordinal is itself an ordinal, and every ordinal is a transitive set (its members are also its subsets; a member of a member of an ordinal is also a member of the ordinal).

Gist of Idea

Members of ordinals are ordinals, and also subsets of ordinals

Source

Michal Walicki (Introduction to Mathematical Logic [2012], 2.3)

Book Reference

Walicki,Michal: 'Introduction to Mathematical Logic' [World Scientific 2012], p.89