A Quote by Benjamin Peirce on paradox, truth, and understanding

After proving Euler's formula e^i = -1 in a lecture: Gentlemen, that is surely true, it is absolutely paradoxical; we cannot understand it, and we don't know what it means. But we have proved it, and therefore we know it is the truth.

Benjamin Peirce (1809 - 1880)

Source: Quoted in E. Kasner and J. Newman, Mathematics and the Imagination, New York 1940

Contributed by: Zaady