Francois Viete (1540-1603) Rene Descartes (1596-1650) He used consonant (B,C,D,....)to denote parameters and vowels (A,E,I,...)to denote variables. Certainly,letters had been used before Viete,but not in actual computations;one letter would be used for a certain quantity,another for its square,and so forth. 2Fran¸cois Vi`ete (1540-1603) Ren´e Descartes (1596-1650) He used consonant (B, C, D, . . ..) to denote parameters and vowels (A, E, I, . . .) to denote variables. Certainly, letters had been used before Vi`ete, but not in actual computations; one letter would be used for a certain quantity, another for its square, and so forth. 2