Knowledge is our ultimate good.

There are beds and tables in the world - plenty of them, are there not? But there are only two ideas or forms of them - one the idea of a bed, the other of a table.

I only know that I know nothing

I have lived long enough to learn how much there is I can really do without.... He is nearest to God who needs the fewest things.

Some have courage in pleasures, and some in pains: some in desires, and some in fears, and some are cowards under the same conditions.

Do you suppose that I should have lived as long as I have if I had moved in the sphere of public life, and conducting myself in that sphere like an honorable man, had always upheld the cause of right, and conscientiously set this end above all other things? Not by a very long way, gentlemen; neither would any other man.

The friend must be like money, that before you need it, the value is known.