Once we know our weaknesses they cease to do us any harm. - Georg Christoph Lichtenberg

What is the good of drawing conclusions from experience? I don't deny we sometimes draw the right conclusions, but don't we just as often draw the wrong ones?

Diogenes, filthily attired, paced across the splendid carpets in Plato's dwelling. Thus, said he, do I trample on the pride of Plato. Yes, Plato replied, but only with another kind of pride.

Do not commence your exercises in philosophy in those regions where an error can deliver you over to the executioner.