When a person supposes that he knows, and does not know; this appears to be the great source of all the errors of the intellect.
The rest of the Dialogue of Critias has been lost.
The soul of man is immortal and imperishable.
No matter at all, I replied; for the point is not who said the words, but whether they are true or not.
False words are not only evil in themselves, but they infect the soul with evil.
The mind more often faints from the severity of study than from the severity of gymnastics: the toil is more entirely the mind's own and is not shared with the body.