Socrates

He is richest who is content with the least, for content is the wealth of nature.

...[M]en are put in a sort of guard-post, from which one must not release one's self or run away...

The only thing I know is that I know nothing, and i am no quite sure that i know that.

Wealth does not bring about excellence, but excellence makes wealth and everything else good for men, both individually and collectively.

wealth does not bring goodness, but goodness brings wealth and every other blessing, both to the individual and to the state

How can you wonder your travels do you no good, when you carry yourself around with you?

I am convinced that I never wrong anyone intentionally...

Be true to thine own self

I went to interview a man with a high reputation for wisdom, because I felt that here if anywhere I should succeed in disproving the oracle and pointing out to my divine authority 'You said that I was the wisest of men, but here is a man who is wiser than I am.' Well, I gave a thorough examination to this person... and in conversation with him I formed the impression that although in many people's opinion, and especially in his own, he appeared to be wise, in fact he was not. Then when I began to try to show him that he only thought he was wise and was not really so, my efforts were resented both by him and by many of the other people present. However, I reflected as I walked away: 'Well, I am certainly wiser than this man. It is only too likely that neither of us has any knowledge to boast of; but he thinks that he knows something which he does not know, whereas I am quite conscious of my ignorance. At any rate it seems that I am wiser than he is to this small extent, that I do not think that I know what I do not know... [A]s I pursued my investigation at the god's command,... my honest impression was... that the people with the greatest reputations were almost entirely deficient, while others who were supposed to be their inferiors were much better qualified in practical intelligence.

To know, is to know that you know nothing. That is the meaning of true knowledge.

...[R]eal wisdom is the property of God, and... human wisdom has little or no value.

If the soul is immortal, it demands our care not only for that part of time which we call life, but for all time; and indeed it would seem now that it will be extremely dangerous to neglect it. If death were a release from everything, it would be a boon for the wicked, because by dying they would be released not only from the body but also from their own wickedness together with the soul; but as it is, since the soul is clearly immortal, it can have no escape of security from evil except by becoming as good and wise as it possibly can. For it takes nothing with it to the next world except its education and training...

One should never do wrong in return, nor mistreat any man, no matter how one has been mistreated by him.

The beginning of wisdom is the definition of terms.

Wonder is the beginning of wisdom.

The only true wisdom is in knowing you know nothing.

God would seem to indicate to us and not allow us to doubt that these beautiful poems are not human, or the work of man, but divine and the work of God; and that the poets are only the interpreters of the Gods...

God takes away the minds of poets, and uses them as his ministers, as he also uses diviners and holy prophets, in order that we who hear them may know them to be speaking not of themselves who utter these priceless words in a state of unconsciousness, but that God himself is the speaker, and that through them he is conversing with us.