TLDR: In the Rennaissance Italy, Maths Duels were a thing. (Mathematicians would be challange eachother to maths duels, their pride and honor on thr line.) Antonio Fior was thaught by Scopione del Ferro (who also was Da Vinci's teacher) how to solve the cubic equation. Del Ferro never published his discovery, because he needed it as a trump card, should he be challanged to a duel. With this trump card in hands Fior challanged Tartaglia to a duel. Fior failed misserably as he could not solve a single problem Tartaglia had given him, while Tartaglia himself had come up with a solution for the cubic equation and solved every single problem Fior had given him.