Reason is, and ought only to be the slave of the passions, and can never pretend to any other office than to serve and obey them.

Custom, then, is the great guide of human life.

Truth springs from argument amongst friends.

It is no more than it is not.

-- Pyrrho

All things are ungraspable.

-- Pyrrho

Things are equally indifferent, unstable, indeterminate.

-- Pyrrho

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

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

-- Democritus