I know nothing but the certainty of my own ignorance.

The first key to greatness is to be in reality what we appear to be.

Do not go through life like leaf blown from here to there believing whatever you are told.

Whenever, therefore, people are deceived and form opinions wide of the truth, it is clear that the error has slid into their minds through the medium of certain resemblances to that truth.

All I know is that I do not know anything

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.

No one does wrong voluntarily.