If men were born free, they would, so long as they remained free, form no conception of good and evil.
Freedom is absolutely necessary for the progress in science and the liberal arts.
Happiness is a virtue, not its reward.
He alone is free who lives with free consent under the entire guidance of reason.
How would it be possible if salvation were ready to our hand, and could without great labor be found, that it should be by almost all men neglected? But all things excellent are as difficult as they are rare.
I call him free who is led solely by reason.
I do not know how to teach philosophy without becoming a disturber of established religion.
I have made a ceaseless effort not to ridicule, not to bewail, not to scorn human actions, but to understand them.
I would warn you that I do not attribute to nature either beauty or deformity, order or confusion. Only in relation to our imagination can things be called beautiful or ugly, well-ordered or confused.
Desire is the essence of a man.
I have striven not to laugh at human actions, not to weep at them, nor to hate them, but to understand them.
Fear cannot be without hope nor hope without fear.
Fame has also this great drawback, that if we pursue it, we must direct our lives so as to please the fancy of men.
If you want the present to be different from the past, study the past.
Desire is the very essence of man.