Mathematics is a game played according to certain simple rules with meaningless marks on paper. D. Hilbert (January 23, 1862 – February 14, 1943)

317 is a prime, not because we think so, or because our minds are shaped in one way rather than another, but because it is, because mathematical reality is built that way. G.H. Hardy (February 7, 1877 - December 1, 1947), A Mathematician's Apology, 1940.