more from Luitzen E.J. Brouwer

Single Idea 12452

[catalogued under 4. Formal Logic / E. Nonclassical Logics / 7. Paraconsistency]

Full Idea

Not to the mathematician, but to the psychologist, belongs the task of explaining why ...we are averse to so-called contradictory systems in which the negative as well as the positive of certain propositions are valid.

Gist of Idea

Our dislike of contradiction in logic is a matter of psychology, not mathematics


Luitzen E.J. Brouwer (Intuitionism and Formalism [1912], p.79)

Book Reference

'Philosophy of Mathematics: readings (2nd)', ed/tr. Benacerraf/Putnam [CUP 1983], p.79

A Reaction

Was the turning point of Graham Priest's life the day he read this sentence? I don't agree. I take the principle of non-contradiction to be a highly generalised observation of how the world works (and Russell agrees with me).