Mephistopheles

“Fas est ab hoste doceri.
One should learn even from one's enemies.”
― Ovid, Metamorphoses

“The road of excess leads to the palace of wisdom.”
― William Blake, The Marriage of Heaven and Hell

“A lady's imagination is very rapid; it jumps from admiration to love, from love to matrimony in a moment.”
― Jane Austen, Pride and Prejudice

“Even in literature and art, no man who bothers about originality will ever be original: whereas if you simply try to tell the truth (without caring twopence how often it has been told before) you will, nine times out of ten, become original without ever having noticed it.”
― C.S. Lewis, Mere Christianity