It is better to change an opinion than to persist in a wrong one.
I am wiser than this man, for neither of us appears to know anything great and good; but he fancies he knows something, although he knows nothing; whereas I, as I do not know anything, so I do not fancy I do.
No man is capable of causing great evil without thinking he's doing the right thing.
He is richest who is content with the least.
We must not let it enter our minds that there may be no validity in argument. On the contrary we should recognize that we ourselves are still intellectual invalids; but that we must brace ourselves and do our best to become healthy... No greater misfortune could happen to anyone than that of developing a dislike for argument.
Esteemed friend, citizen of Athens, the greatest city in the world, so outstanding in both intelligence and power, aren't you ashamed to care so much to make all the money you can, and to advance your reputation and prestige--while for truth and wisdom and the improvement of your soul you have no care or worry?