When asked what learning was the most necessary, he said, Not to unlearn what you have learned!
Diogenes LaertiusDiogenes said once to a person who was showing him a dial, "It is a very useful thing to save a man from being too late for supper.
Diogenes LaertiusPlato affirmed that the soul was immortal and clothed in many bodies successively.
Diogenes Laertius