Single Idea 14107

[catalogued under 9. Objects / F. Identity among Objects / 7. Indiscernible Objects]

Full Idea

Two terms are identical when the second belongs to every class to which the first belongs.

Gist of Idea

Terms are identical if they belong to all the same classes

Source

Bertrand Russell (The Principles of Mathematics [1903], §026)

Book Reference

Russell,Bertrand: 'Principles of Mathematics' [Routledge 1992], p.23

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