In teaching man, experimental science results in lessening his pride more and more by proving to him every day that primary causes, like the objective reality of things, will be hidden from him forever and that he can only know relations.
Obervation is a passive science, experimentation is an active science.
Hatred is the most clear- sighted, next to genius.
It is what we know already that often prevents us from learning.
True science teaches us to doubt and, in ignorance, to refrain.
The minds that rise and become really great are never self-satisfied, but still continue to strive.