more from Penelope Maddy

### Single Idea 18196

#### [catalogued under 6. Mathematics / A. Nature of Mathematics / 5. The Infinite / i. Cardinal infinity]

Full Idea

An 'inaccessible' cardinal is one that cannot be reached by taking unions of small collections of smaller sets or by taking power sets.

Gist of Idea

An 'inaccessible' cardinal cannot be reached by union sets or power sets

Source

Penelope Maddy (Naturalism in Mathematics [1997], I.5)

Book Reference

Maddy,Penelope: 'Naturalism in Mathematics' [OUP 2000], p.74

A Reaction

They were introduced by Hausdorff in 1908.