Animals, we have been told, are taught by their organs. Yes, I would add, and so are men, but men have this further advantage that they can also teach their organs in return.

People will allow their faults to be shown them; they will let themselves be punished for them; they will patiently endure many things because of them; they only become impatient when they have to lay them aside.

Every solution of a problem is a new problem.

Hypotheses are only the pieces of scaffolding which are erected round a building during the course of construction, and which are taken away as soon as the edifice is completed.

We amuse ourselves painting our prison-walls with bright figures and brilliant landscapes.

‎It has ever been my fate to give pain to those whose happiness I should have promoted.

Superstition is the poetry of life. It is inherent in man's nature; and when we think it is wholly eradicated, it takes refuge in the strangest holes and corners, whence it peeps out all at once, as soon as it can do it with safety.