The Selected Correspondence of L.E.J. Brouwer Quotes

“It [logical reasoning] serves only lawyers and demagogues, not to instruct other people but to deceive them, and that is because the vulgar herd unconsciously reasons: the language with its logical figures is there, so it will be useful and so they meekly let themselves be deceived; just as I heard several people defend their habit of gin drinking with the words: ‘What else is gin for?’ Whoever has the illusion to improve the world, may just as well agitate against the language of logical reasoning as against alcohol.”
― L.E.J. Brouwer, The Selected Correspondence of L.E.J. Brouwer

“Regarding your remark that the name of Kant doesn’t belong in a mathematical dissertation: you will see that the 'Foundations' of Russell deal repeatedly with Kant, & that ‘The Principles of Mathematics’ of Couturat are completed with an Appendix of over 100 pages about Kant. And when you compare the Transcendental Aesthetics of Kant to these, you will see that he speaks about exactly the same things as Russell and Couturat. And Poincaré points out that the present struggle about the foundations is a continuation of the old mathematical-philosophical controversy between Kant & Leibniz. Even though the name of Kant can be avoided here—his subjects are touched upon; is it then necessary to avoid his name because he is known as a philosopher? (Brouwer, 1906 letter to Korteweg)”
― L.E.J. Brouwer, The Selected Correspondence of L.E.J. Brouwer

“One knows well that the world is not a logical system and one cannot argue logically about it.”
― L.E.J. Brouwer, The Selected Correspondence of L.E.J. Brouwer

“The mathematics of whole and part [=syllogistic] does not teach us through its theory anything new for application. Once the system is applied to a part of the observational world, even a very mediocre intellect can immediately read off all the consequences: no intermediary logical reasoning is necessary.”
― L.E.J. Brouwer, The Selected Correspondence of L.E.J. Brouwer