These three things-work, will, success-fill human existences. Will opens the door to success, both brilliant and happy. Work passes these doors, and at the end of the journey success comes in to crown one's efforts.

Imagination should give wings to our thoughts but we always need decisive experimental proof, and when the moment comes to draw conclusions and to interpret the gathered observations, imagination must be checked and documented by the factual results of the experiment.

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

It is not the germs we need worry about. It is our inner terrain.

Since the most ancient times, all men, and particularly those who endeavored in the practice of medicine, have brought closer together two natural phenomena of capital importance: illness or fever and fermentation.

Posterity will one day laugh at the sublime foolishness of the modern materialistic philosophy. The more I study nature, the more I stand amazed at the work of the Creator. I pray while I am engaged at my work in the laboratory.

The greatest derangement of the mind is to believe in something because one wishes it to be so.