9 2 



was about to publish certain new mathematical rules in 

 a book on Algebra, and hinting that in all probability 

 these rules would prove to be Tartaglia's, whereupon he 

 at once jumped to the conclusion that Maphio's gossip 

 was the truth, and that this book would make public 

 the secret which Cardan had sworn to keep. He left 

 many of Cardan's letters unanswered ; but at last he 

 seems to have found too strong the temptation to say 

 something disagreeable ; so, in answer to a letter from 

 Cardan containing a request for help in solving an 

 equation which had baffled his skill, Tartaglia wrote 

 telling Cardan that he had bungled in his application of 

 the rule, and that he himself was now very sorry he had 

 ever confided the rule aforesaid to such a man. He ends 

 with further abuse of Cardan's Practice of Arithmetic, 

 which he declares to be merely a confused farrago of 

 other men's knowledge, 1 and with a remark which he 

 probably intended to be a crowning insult. " I well 

 remember when I was at your house in Milan, that you 

 told me you had never tried to discover the rule of the 

 cosa and the cubus equal to the numerus which was 

 found out by me, because Fra Luca had declared it to be 

 impossible ; 2 as if to say that, if you had set yourself to 

 the task you could have accomplished it, a thing which 

 sets me off laughing when I call to mind the fact that it 



1 u Non ha datta fora tal opera come cose composto da sua testa 

 ma come cose ellette raccolte e copiate de diverse libri a penna." 

 Quesitt ' et Inventioni, p. 127. 



2 Cardan repeats the remark in the first chapter of the Liber 

 Artis Magna (Opera, torn. iv. p. 222). " Deceptus enim ego verbis 

 Lucae Paccioli, qui ultra sua capitula, generale ullum aliud esse posse 

 negat (quanquam tot jam antea rebus a me inventis, sub manibus 

 esset) desperabam tamen invenire, quod quaerere non audebam." 

 Perhaps he wrote them down as an apology or a defence against the 

 storm which he anticipated as soon as Tartaglia should have seen 

 the new Algebra. 



