Augustin-Louis Cauchy

View the biography of Augustin-Louis Cauchy

Men pass away, but their deeds abide.
Possibly his last words. Quoted in H Eves Mathematical Circles Revisited (Boston 1971).
√-1 we can repudiate completely and which we can abandon without regret because one does not know what this pretended sign signifies nor what sense one ought to attribute to it.
Writing in 1847 in regard to the square root of negative one.
As for methods I have sought to give them all the rigour that one requires in geometry, so as never to have recourse to the reasons drawn from the generality of algebra.