On the basis of discrepancies observed in the orbit of Neptune and aberrations yet unexplained in the orbit of Uranus, the existence of a further planet was posited by the American astronomer Percival Lowell, which led to its discovery in 1930 by Clyde Tombaugh. After much consideration among many alternatives, the new planet was named Pluto, god of the underworld. Observations of potential correlations with Pluto by astrologers in the subsequent decades suggested that the qualities associated with the new planet in fact bore a striking relevance to the mythic character of Pluto, the Greek Hades, and also to the figure of Dionysus, with whom Hades-Pluto was closely associated by the Greeks. (Both Heraclitus and Euripides identified Dionysus and Hades as one and the same deity.) Closely analogous to Freud’s concept of the primordial id, “the broiling cauldron of the instincts,” and to Darwin’s understanding of an ever-evolving nature and the biological struggle for existence, the archetype associated with the planet Pluto is also linked to Nietzsche’s Dionysian principle and the will to power and to Schopenhauer’s blind striving universal will—all these embodying the powerful forces of nature and emerging from nature’s chthonic depths, within and without, the intense, fiery elemental underworld. Again, as with both Uranus and Neptune, so also in Pluto’s case the mythological domain and element associated with the new planet’s given name appear to be poetically accurate, but here the archetypal parallels between the mythic figure and the observed qualities are especially extensive.