There is also a third kind of madness, which is possession by the Muses, enters into a delicate and virgin soul, and there inspiring frenzy, awakens lyric... But he, who, not being inspired and having no touch of madness in his soul, comes to the door and thinks he will get into the temple by the help of art - he, I say, and his poetry are not admitted; the sane man is nowhere at all when he enters into rivalry with the madman.
PlatoIn good speaking, should not the mind of the speaker know the truth of the matter about which he is to speak.
Plato