Single Idea 21539

[catalogued under 5. Theory of Logic / D. Assumptions for Logic / 2. Excluded Middle]

Full Idea

The law of excluded middle may be stated in the form: If p is denied, not-p must be asserted; this form is too psychological to be ultimate, but the point is that it is significant and not a mere tautology.

Gist of Idea

Excluded middle can be stated psychologically, as denial of p implies assertion of not-p

Source

Bertrand Russell (Meinong on Complexes and Assumptions [1904], p.41)

Book Reference

Russell,Bertrand: 'Essays in Analysis', ed/tr. Lackey,Douglas [George Braziller 1973], p.41


A Reaction

'Psychology' is, of course, taboo, post-Frege, though I think it is interesting. Stated in this form the law looks more false than usual. I can be quite clear than p is unacceptable, but unclear about its contrary.