Nearly all men are slaves for ...

Nearly all men are slaves for the same reason that the Spartans assigned for the servitude of the Persians -- lack of power to pronounce the syllable, "No." To be able to utter that word and live alone, are the only means to preserve one's freedom and one's character.
 Nicolas Chamfort

Quotes from the same author

There are more fools than wise men, and even in a wise man there is more folly than wisdom.
 Nicolas Chamfort
Men whose only concern is other people's opinion of them are like actors who put on a poor performance to win the applause of people of poor taste; some of them would be capable of good acting in front of a good audience. A decent man plays his part to the best of his ability, regardless of the taste of the gallery.
 Nicolas Chamfort
One can be certain that every generally held idea, every received notion, will be idiocy because it has been able to appeal to the majority
 Nicolas Chamfort
Stupidity would not be absolute stupidity did it not fear intelligence.
 Nicolas Chamfort
In love, everything is true, everything is false; it is the one subject on which one cannot express an absurdity.
 Nicolas Chamfort