About L. E. J. Brouwer
Luitzen Egbertus Jan "Bertus" Brouwer was a Dutch mathematician and philosopher who worked in topology, set theory, measure theory and complex analysis. Regarded as one of the greatest mathematicians of the 20th century, he is known as one of the founders of modern topology, particularly for establishing his fixed-point theorem and the topological invariance of dimension. Among mathematicians generally, the best known is the first one, usually referred to now as the Brouwer fixed point theorem. Brouwer founded intuitionism, a philosophy of mathematics that challenged the then-prevailing formalism of David Hilbert and his collaborators, who included Paul Bernays, Wilhelm Ackermann, and John von Neumann (cf. Brouwer also became a major figure in the philosophy of intuitionism, a constructivist school of mathematics which argues that mathematics is a cognitive construct rather than a type of objective truth. In later years Brouwer became relatively isolated; the development of intuitionism at its source was taken up by his student Arend Heyting.
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