more from Graham Priest

### Single Idea 13369

#### [catalogued under 5. Theory of Logic / L. Paradox / 4. Paradoxes in Logic / d. Richard's paradox]

Full Idea

Richard: φ(x) is 'x is a definable real number between 0 and 1' and ψ(x) is 'x is definable'. We can define a real by diagonalization so that it is not in x. It is and isn't in the set of reals.

Gist of Idea

By diagonalization we can define a real number that isn't in the definable set of reals

Source

Graham Priest (The Structure of Paradoxes of Self-Reference [1994], §3)

Book Reference

-: 'Mind' [-], p.29

A Reaction

[this isn't fully clear here because it is compressed]