Single Idea 10582

[catalogued under 18. Thought / E. Abstraction / 7. Abstracta by Equivalence]

Full Idea

The principle of Abstraction says that whenever a relation with instances is symmetrical and transitive, then the relation is not primitive, but is analyzable into sameness of relation to some other term. ..This is provable and states a common assumption.

Gist of Idea

The principle of Abstraction says a symmetrical, transitive relation analyses into an identity

Source

Bertrand Russell (The Principles of Mathematics [1903], §157)

Book Reference

Russell,Bertrand: 'Principles of Mathematics' [Routledge 1992], p.166


A Reaction

At last I have found someone who explains the whole thing clearly! Bertrand Russell was wonderful. See other ideas on the subject from this text, for a proper understanding of abstraction by equivalence.