One and the same thing can at the same time be good, bad, and indifferent, e.g., music is good to the melancholy, bad to those who mourn, and neither good nor bad to the deaf.

Everything in nature is a cause from which there flows some effect.

Everyone has as much right as he has might.

I can control my passions and emotions if I can understand their nature

Men believe themselves to be free, simply because they are conscious of their actions, and unconscious of the causes whereby those actions are determined.

After experience had taught me that all the usual surroundings of social life are vain and futile; seeing that none of the objects of my fears contained in themselves anything either good or bad, except in so far as the mind is affected by them, I finally resolved to inquire whether there might be some real good having power to communicate itself, which would affect the mind singly, to the exclusion of all else: whether, in fact, there might be anything of which the discovery and attainment would enable me to enjoy continuous, supreme, and unending happiness.

Of all the things that are beyond my power, I value nothing more highly than to be allowed the honor of entering into bonds of friendship with people who sincerely love truth. For, of things beyond our power, I believe there is nothing in the world which we can love with tranquility except such men.