Where observation is concerned, chance favors only the prepared mind.

I give them experiments and they respond with speeches.

My opinion - nay more, my conviction - is that, in the present state of science, as you rightly say, spontaneous generation is a chimera; and it would be impossible for you to contradict me, for my experiments all stand forth to prove that spontaneous generation is a chimera.

The universe is an asymmetrical entity. I am inclined to believe that life as it is manifested to us must be a function of the asymmetry of the universe or of the consequence of this fact. The universe is asymmetrical; for if one placed the entire set of bodies that compose the solar system, each moving in its own way, before a mirror, the image shown would not be superimposable on the reality.

Blessed is he who carries within himself a God, an ideal, and obeys it.

Science knows no country because it is the light that iluminates the world

When I approach a child, he inspires in me two sentiments; tenderness for what he is, and respect for what he may become.