Do not let yourself be tainted with a barren skepticism.

There are two men in each one of us: the scientist, he who starts with a clear field and desires to rise to the knowledge of Nature through observations, experimentation and reasoning, and the man of sentiment, the man of belief, the man who mourns his dead children, and who cannot, alas, prove that he will see them again, but who believes that he will, and lives in the hope – the man who will not die like a vibrio, but who feels that the force that is within him cannot die.

... by chance you will say, but chance only favors the mind which is prepared.

You bring me the deepest joy that can be felt by a man whose invincible belief is that Science and Peace will triumph over Ignorance and War, that nations will unite, not to destroy, but to build, and that the future will belong to those who will have done most for suffering humanity.

The grandeur of the acts of men are measured by the inspiration from which they spring.

If you suppress laboratories, physical science will be stricken with barrenness and death.

Science knows no country, because knowledge belongs to humanity, and is the torch which illuminates the world.