Abel has left mathematicians enough to keep them busy for five hundred years.

My cousin. His name is Abel. He is two years older than I. Next to my father, he is dearest to my heart.

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...