He, who knows how to distinguish between true and false, must have an adequate idea of true and false.

He who has a true idea, knows at that same time that he has a true idea, nor can he doubt concerning the truth of the thing.

Indulge yourself in pleasures only in so far as they are necessary for the preservation of health.

When a man is prey to his emotions, he is not his own master.

From what has been said we can clearly understand the nature of Love and Hate. Love is nothing else but pleasure accompanied by the idea of an external cause: Hate is nothing else but pain accompanied by the idea of an external cause. We further see, that he who loves necessarily endeavors to have, and to keep present to him, the object of his love; while he who hates endeavors to remove and destroy the object of his hatred.

He whose honor depends on the opinion of the mob must day by day strive with the greatest anxiety, act and scheme in order to retain his reputation. For the mob is varied and inconsistent, and therefore if a reputation is not carefully preserved it dies quickly.

The more a government strives to curtail freedom of speech, the more obstinately is it resisted; not indeed by the avaricious, ... but by those whom good education, sound morality, and virtue have rendered more free.