I am myself the matter of my book.

Because it was he; because it was I.

The greatest thing in the world is to know how to be at home in oneself.

All things are ungraspable.

-- Pyrrho

Color exists by convention, sweet by convention, bitter by convention; in reality there are only atoms and void.

-- Democritus

I know that I know nothing.

-- Socrates

You must learn all things: both the steadfast heart of well-rounded Truth and the opinions of mortals, in which there is no true trust.

-- Parmenides

For thinking and Being are the same.

-- Parmenides

Imagine prisoners chained underground since childhood, seeing only shadows on a wall and taking them for reality.

-- Plato