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.

What did you do today to receive your instruction?

I have the faith of a Breton peasant and by the time I die I hope to have the faith of a Breton peasant's wife.

Without theory, practice is but routine born of habit. Theory alone can bring forth and develop the spirit of inventions.

In good philosophy, the word cause ought to be reserved to the single Divine impulse that has formed the universe.

My present and most fixed opinion regarding the nature of alcoholic fermentation is this: The chemical act of fermentation is essentially a phenomenon correlative with a vital act, beginning and ending with the latter. I believe that there is never any alcoholic fermentation without their being simultaneously the organization, development, multiplication of the globules, or the pursued, continued life of globules which are already formed.

When one works and imagines and dreams of nothing else than the search for answers that God has posed, it is difficult to be so still.