Prejudices are the refuge of those who cannot think for themselves.
We often make people pay dearly for what we think we give them.
The best way to find out if a man has done something is to advise him to do it. He will not be able to resist boasting that he has done it without being advised.
Doubt is a necessity of the mind, faith of the heart.
You should only confide your secrets to someone who has not tried to guess them.