"A mathematician is a blind man in a dark room looking for a black cat
which isn't there" - Charles R. Darwin (1809-1882) [English biologist]
Copernicus, Nicholaus (1473-1543)
Mathematics is written for mathematicians.
Life is good for only two things, discovering mathematics and teaching
If I feel unhappy, I do mathematics to become happy. If I am happy, I do mathematics to keep happy.
P. Turan, "The Work of Alfred Renyi", Matematikai Lapok 21, 1970, pp 199-210