Whether our efforts are, or not, favored by life, let us be able to say, when we come near to the great goal, I have done what I could.

If it is a terrifying thought that life is at the mercy of the multiplication of these minute bodies [microbes], it is a consoling hope that Science will not always remain powerless before such enemies.

We affirm the neutrality of Science ... Science is of no country. ... But if Science has no country, the scientist must keep in mind all that may work towards the glory of his country. In every great scientist will be found a great patriot.

Little science takes you away from God but more of it takes you to Him.

In matters of observation chance favors only the prepared mind. (not literal translation) - Dan's les champs de observation le hasard ne favorise que les esprits prepares.

Preconceived ideas are like searchlights which illumine the path of the experimenter and serve him as a guide to interrogate nature. They become a danger only if he transforms them into fixed ideas-this is why I should like to see these profound words inscribed on the threshold of all the temples of science: 'The greatest derangement of the mind is to believe in something because one wishes it to be so.'

My strength lies solely in my tenacity.