Luitzen Egbertus Jan Brouwer

Luitzen Egbertus Jan Brouwer, (1881 - 1966) usually cited as "L.E.J. Brouwer", was a Dutch mathematician who worked in topology, set theory, and measure theory and complex analysis. The Brouwer fixed point theorem is named eponymously in his honor.

Brouwer adhered to an intuitionist philosophy of mathematics, which is sometimes characterized by saying that its adherents refuse to use the law of excluded middle in mathematical reasoning, and wrote books on the subjects mentioned above in which he proceeded accordingly.