The one self- knowledge worth having is to know one's own mind.

Reason teaches us that what is good is good for something, and that what is good for nothing is not good at all.

My external sensations are no less private to my self than are my thoughts or my feelings. In either case my experience falls within my own circle, a circle closed on the outside... the whole world for each is peculiar and private to that soul.

It is by a wise economy of nature that those who suffer without change, and whom no one can help, become uninteresting. Yet so it may happen that those who need sympathy the most often attract it the least.

Eclecticism. Every truth is so true that any truth must be false.

Up to a certain point every man is what he thinks he is.

There are those who so dislike the nude that they find something indecent in the naked truth.