Education is the progressive discovery of our own ignorance.
There is only one good, knowledge, and one evil, ignorance.
Every man who rises above the common level has received two educations: the first from his teachers; the second, more personal and important, from himself.
For man, the unexamined life is not worth living.
One only sees what one looks for, one only looks for what one knows.
This alone I know, that I know nothing.