The Adventures of Yusuf Al-Muʾtaman ibn Hud and Giovanni Ceva

[Source]

Wrote the great Yusuf Al-Muʾtaman ibn Hud, the King of Zaragoza, in his magnum opus, the Kitab al-Istikmal: "... Thus, I have proven that if these three ratios on the triangle give a product of one, then these three lines in the triangle meet in a point!"

After having read this proof, the scholars in his court exclaimed: "Truly, this is an important proof! O, great King Yusuf Al-Muʾtaman ibn Hud, you are indeed called the Sage of Zaragoza; your name shall be spread far and wide, even down all the generations!"

Six hundred years later, in a dusty university room in Mantua, the Jesuit Professor Giovanni Ceva realises, with a serendipitous spark of inspiration, the same truth that had been discovered by the great Yusuf Al-Muʾtaman ibn Hud. He publishes it and we now name it Ceva's Theorem because his name is easier to pronounce.