No one shall expel us from the paradise which Cantor has created for us.{Expressing the importance of Georg Cantor's set theory in the development of mathematics.}

The infinite! No other question has ever moved so profoundly the spirit of man.

Before beginning [to try to prove Fermat's Last Theorem] I should have to put in three years of intensive study, and I haven't that much time to squander on a probable failure.

The arithmetical symbols are written diagrams and the geometrical figures are graphic formulas.

Besides it is an error to believe that rigour is the enemy of simplicity. On the contrary we find it confirmed by numerous examples that the rigorous method is at the same time the simpler and the more easily comprehended. The very effort for rigor forces us to find out simpler methods of proof.