The supreme mystery of despotism, its prop and stay, is to keep men in a state of deception, and with the specious title of religion to cloak the fear by which they must be held in check, so that they will fight for their servitude as if for salvation.

We strive to further the occurrence of whatever we imagine will lead to Joy, and to avert or destroy what we imagine is contrary to it, or will lead to Sadness.

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

Those who wish to seek out the cause of miracles and to understand the things of nature as philosophers, and not to stare at them in astonishment like fools, are soon considered heretical and impious, and proclaimed as such by those whom the mob adores as the interpreters of nature and the gods.

If the way which I have pointed out as leading to this result (i.e., power over the emotions by which the wise man surpasses the ignorant man) seems exceedingly hard, it may nevertheless be discovered. Needs must it be hard, since it is so seldom found. How would it be possible, if salvation were ready to our hand, and could without great labour be found, that it should be by almost all men neglected? But all things excellent are as difficult as they are rare.

Fear cannot be without hope nor hope without fear.

Nothing comes to pass in nature, which can be set down to a flaw therein; for nature is always the same, and everywhere one and the same in her efficacy and power of action: that is, nature's laws and ordinances, whereby all things come to pass and change from one form to another, are everywhere and always the same; so that there should be one and the same method of understanding the nature of all things whatsoever, namely, through nature's universal laws and rules.