Single Idea 9826

[catalogued under 6. Mathematics / A. Nature of Mathematics / 5. The Infinite / b. Mark of the infinite]

Full Idea

A system S is said to be infinite when it is similar to a proper part of itself.

Clarification

We would now call a 'system' a 'set'

Gist of Idea

A system S is said to be infinite when it is similar to a proper part of itself

Source

Richard Dedekind (Nature and Meaning of Numbers [1888], V.64)

Book Reference

Dedekind,Richard: 'Essays on the Theory of Numbers' [Dover 1963], p.63

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