Bernard was right. The germ is nothing, the terrain is everything.

There is no such thing as applied science, only the application of pure science.

Live in the serene peace of laboratories and libraries

Without theory, practice is but routine born of habit. Theory alone can bring forth and develop the spirit of invention. ... [Do not] share the opinion of those narrow minds who disdain everything in science which has not an immediate application. ... A theoretical discovery has but the merit of its existence: it awakens hope, and that is all. But let it be cultivated, let it grow, and you will see what it will become.

Do not put forward anything that you cannot prove by experimentation.

Nothing is lost and nothing is created in the operations of art as those of nature.

Science belongs to no one country.