Misanthropy ariseth from a man trusting another without having sufficient knowledge of his character, and, thinking him to be truthful, sincere, and honourable, finds a little afterwards that he is wicked, faithless, and then he meets with another of the same character. When a man experiences this often, and more particularly from those whom he considered his most dear and best friends, at last, having frequently made a slip, he hates the whole world, and thinks that there is nothing sound at all in any of them.
PlatoRhythm and harmony enter most powerfully into the inner most part of the soul and lay forcible hands upon it, bearing grace with them, so making graceful him who is rightly trained.
Plato