The Birth of Tragedy Out of the Spirit of Music: An Attempt at Self-Criticism

We will have achieved much for the study of aesthetics when we come, not merely to a logical understanding, but also to the immediately certain apprehension of the fact that the further development of art is bound up with the duality of the Apollonian and the Dionysian, just as reproduction depends upon the duality of the sexes, their continuing strife and only periodically occurring reconciliation