It is a true man's part not to err, but it is also noble of a man to perceive his error.

In my travels, which have been wider than ever man yet accomplished, I have seen many, many wild beasts of Arabia and India; but this beast, that is commonly called a Tyrant, I know not how many heads it has, nor if it be crooked of claw, and armed with horrible fangs.

If any man has left us for fear of Nero, I shall not account him a coward; but I shall hail as a philosopher any man who has been superior to this fear, and I shall teach him all I know.

Apollonius of Tyana Quotes