Single Idea 8302

[catalogued under 6. Mathematics / B. Foundations for Mathematics / 5. Definitions of Number / d. Hume's Principle]

Full Idea

What is now known as Hume's Principle says the number of Fs is identical with the number of Gs if and only if the Fs and the Gs are one-to-one correlated with one another.

Gist of Idea

Fs and Gs are identical in number if they one-to-one correlate with one another

Source

E.J. Lowe (The Possibility of Metaphysics [1998], 10.3)

Book Reference

Lowe,E.J.: 'The Possibility of Metaphysics' [OUP 2001], p.214


A Reaction

This seems popular as a tool in attempts to get the concept of number off the ground. Although correlations don't seem to require numbers ('find yourself a partner'), at some point you have to count the correlations. Sets come first, to identify the Fs.