It is true that Fourier had the opinion that the principal aim of mathematics was public utility and explanation of natural phenomena; but a philosopher like him should have known that the sole end of science is the honor of the human mind, and that under this title a question about numbers is worth as much as a question about the system of the world.
Man muss immer generalisieren
[One should always generalise].
The real end of science is the honour of the human mind.
It is often more convenient to possess the ashes of great men than to possess the men themselves during their lifetime.
Mathematics is the science of what is clear by itself.
The God that reigns in Olympus is Number Eternal.
Mathematics exists solely for the honour of the human 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 ...