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mathematics

	Euclide's Mistakes 2018-06-21 by John-Erik Persson The fifth postulate In Euclid's geometry, regarding a plane, he uses the concepts point and straight line. He postulates, that a point and a straight line together can define a unique straight line, parallel to the given line and passing through the given point. However, he never provided

	Euclid Was Wrong 2015-08-12 by John-Erik Persson An earlier contribution from this author was called The Definition of Parallelism. The article stated that the definition of parallelism in Euclidean geometry is wrong. The motivat