Ongoing collection of quotes attributed (mod my lapses in memory) to mathematicians and physicists or about their work:
Go forward, faith will follow!
I have always thought that morality in politics was something essential, just like feelings and affinities.
To discover something in mathematics is to overcome an inhibition and a tradition. You cannot move forward if you are not subversive.
Jean Baptiste Joseph Fourier (1768–1830)
Mathematics compares the most diverse phenomena and discovers the secret analogies that unite them.
Physics is imagination in a straitjacket.
When in doubt, integrate by parts.
We leave the operators, as Jeans said, “hungry for something to differentiate.”
Sophia Kovalevskaya (1850–1891)
It is not possible to be a mathematician without being a poet at heart.
Anonymous quote (in an anecdote, probably by Gian-Carlo Rota)
I do discrete, not continuous.
Schwartz’s theory of distributions is an example of the French propensity to turn an operation into a theory–in this case, integration by parts.
In these days the angel of topology and the devil of abstract algebra fight for the soul of every individual discipline of mathematics.