Moritz Cantor

“ Another idea of Stevinus, for which even Hugo Grotius gave him great credit, was his notion of a bygone age of wisdom. The goal to be aimed at is the bringing about of a second age of wisdom, in which mankind shall have recovered all its early knowledge. The fellow-countrymen of Stevinus were proud that he wrote in their own dialect, which he thought fitted for a universal language, as no other abounded like Dutch in monosyllabic radical words. ”

“ Leonardo’s method, therefore, when the difference was a fixed condition of the problem, was necessarily very different from the Arabian, and, in all probability, was his own discovery. The Flos of Leonardo turns on the second question set by John of Palermo, which required the solution of the cubic equation x3 + 2x2 + 10x=20. Leonardo, making use of fractions of the sexagesimal scale, gives x=10 22i 7ii 42iii 33iv 4v 40vi, after having demonstrated, by a discussion founded on the 10th book of Euclid, that a solution by square roots is impossible. ”

“ In his Practica geometriae plain traces of the use of the Roman agrimensores are met with; in his Liber abaci old Egyptian problems reveal their origin by the reappearance of the very numbers in which the problem is given, though one cannot guess through what channel they came to Leonardo’s knowledge. Leonardo cannot be regarded as the inventor of that very great variety of truths for which he mentions no earlier source. ”