What is evil? Whatever springs from weakness. 
It takes a great talent and skill to conceal one's talent and skill. 
Man is an animal that makes bargains: no other animal does this - no dog exchanges bones with another. 
We should not be upset that others hide the truth from us, when we hide it so often from ourselves. 
Hell is other people. 
There are two kinds of lies; one concerns an accomplished fact, the other concerns a future duty. 
Nothing is as dangerous as an ignorant friend; a wise enemy is to be preferred. 
Abandon all hope, ye who enter here. 
Man is condemned to be free. 
Every man has in himself the most dangerous traitor of all. 
What people commonly call fate is mostly their own stupidity. 
Genius lives only one story above madness. 