[On Cantor's work:] The finest product of mathematical genius and one of the supreme achievements of purely intellectual human activity.

As long as a branch of science offers an abundance of problems, so long it is alive; a lack of problems foreshadows extinction or the cessation of independent development.

If I were to awaken after having slept for a thousand years, my first question would be: Has the Riemann hypothesis been proven?

The tool which serves as intermediary between theory and practice, between thought and observation, is mathematics; it is mathematics which builds the linking bridges and gives the ever more reliable forms.

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

Physics is becoming too difficult for the physicists.

Geometry is the most complete science.