As a preliminary, it is necessary to consider the origin of the tetralogy in Greek drama, and the evidence regarding the period of time during which tetralogy was in use.
Among the deities of ancient Greece, it was peculiar to the young Dionysus,—that latest comer from the East,—that, according to legend, he had not been permitted to assume his place in the pantheon without resistance at the hands of men. His entrance into Hellas had been opposed; his worshippers had been harassed; in his own person he had endured contumely, even bonds: but in the end he prevailed; the frowardness which thwarted the enthusiasm of his votaries was turned by him into a darker ecstasy of madness and self-destruction.
