“When one day Lagrange took out of his pocket a paper which he read at the Académe, and which contained a demonstration of the famous Postulatum of Euclid, relative to the theory of parallels. This demonstration rested on an obvious paralogism, which appeared as such to everybody; and probably Lagrange also recognised it such during his lecture. For, when he had finished, he put the paper back in his pocket, and spoke no more of it. A moment of universal silence followed, and one passed immediately to other concerns.” ScienceMathematicsMathEuclidLagrangeJoseph Louis LagrangeGiuseppe Luigi LagranciaTheory Of Parallels Author:Jean-Baptiste Biot