God ever arithmetizes.
Quoted in H Eves Mathematical Circles Revisited (Boston 1971).
Man muss immer generalisieren
One should always generalize.
Quoted in P Davis and R Hersh The Mathematical Experience (Boston 1981).
The real end of science is the honour of the human mind.
Quoted in H Eves In Mathematical Circles (Boston 1969).
It is often more convenient to possess the ashes of great men than to possess the men themselves during their lifetime.
[Commenting on the return of Descartes' remains to France]
Quoted in H Eves Mathematical Circles Adieu (Boston 1977).
Mathematics is the science of what is clear by itself.
Quoted in J R Newman, The World of Mathematics (New York 1956).
The God that reigns in Olympus is Number Eternal.
Quoted in T Dantzig, Number: the Language of Science
Mathematics exists solely for the honour of the human mind.
Quoted in W R Fuchs, Mathematics for the Modern Mind
Dirichlet alone, not I, nor Cauchy, nor Gauss knows what a completely rigorous mathematical proof is. Rather we learn it first from him. When Gauss says that he has proved something, it is very clear; when Cauchy says it, one can wager as much pro as con; when Dirichlet says it, it is certain ...
Quoted in G Schubring, Zur Modernisierung des Studiums der Mathematik in Berlin, 1820-1840.