G.H. Hardy

No mathematician should ever allow him to forget that mathematics, more than any other art or science, is a young man's game. _ Galois died at twenty-one, Abel at twenty-seven, Ramanujan at thirty-three, Riemann at forty. There have been men who have done great work later; _ [but] I do not know of a single instance of a major mathematical advance initiated by a man past fifty. _ A mathematician may still be competent enough at sixty, but it is useless to expect him to have original ideas.

[It] is hardly possible to maintain seriously that the evil done by science is not altogether outweighed by the good. For example, if ten million lives were lost in every war, the net effect of science would still have been to increase the average length of life.

Archimedes will be remembered when Aeschylus is forgotten, because languages die and mathematical ideas do not. __mmortality_ may be a silly word, but probably a mathematician has the best chance of whatever it may mean.