Nikolai Ivanovich Lobachevski (1792-1856)

Lobachevski, as many other mathematicians at that time, tried to address the dilemma in the Euclid's fifth postulate. He recognized that no actual proofs have been written about it and that most of what mathematicians came up with were nothing more than mere explanations. Although he became blind a year before his death, he wrote about his research on the new theory of parallels. His book was published in French and is entitled: "Pangeometrie ou précis de gometrie fondee sur une theorie general et rigoureuse des paralleles" (Wolfe, 1945, p.55). Lobachevski did not live to witness his success, however, Gauss has described his work as "[…] contain[ing] the elements which must hold, and can with strict consistency hold, if the Euclidean is not true […]" (Wolfe, 1945, p.55)

Reference: Wolf, H.E. (1945). Introduction to non-Euclidean geometry
Nikolai Ivanovich, n.d., n.t., google image, retrieved on 4/11/2009
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