Put off your imagination, as you put off your overcoat, when you enter the laboratory. Put it on again, as you put on your overcoat, when you leave. – Claude Bernard
A fact in itself is nothing. It is valuable only for the idea attached to it, or for the proof which it furnishes. – Claude Bernard
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. – Claude Bernard
The doubter is a true man of science; he doubts only himself and his interpretations, but he believes in science. – Claude Bernard