Contrast introduced by Nietzsche in The Birth of Tragedy (1872) between the spirit of order, rationality, and intellectual harmony, represented by Apollo, and the spirit of ecstatic, spontaneous will to life, represented by Dionysius. In later writings Apollo became, confusingly, more identified with Christian virtues, leaving a calm classicist such as Goethe oddly classified as a Dionysian figure.
Philosophy dictionary. Academic. 2011.