A further question arose: Assuming that ultimately the elements of knowable existence are but two, the One or Definite, and the Manifold or Indefinite, it was argued by some that there must be some third or higher principle governing the relations of these; there must be some law or harmony which shall render their intelligible union [57] possible. This principle of union was God, ever-living, ever One, eternal, immovable, self-identical. [58] This was the supreme reality, the Odd-Even or Many in One, One in Many, in whom was gathered up, as in an eternal harmony, all the contrarieties of lower [61] existence. Through the interchange and intergrowth of these contrarieties God realises Himself; the {27} universe in its evolution is the self-picturing of God. [62] God is diffused as the seminal principle throughout [68] the universe; He is the Soul of the world, and the world itself is God in process. The world, therefore, is in a sense a living creature. At its heart and circumference are purest fire; between these circle the sun, the moon, and the five planets, whose ordered movements, as of seven chords, produce an eternal music, the 'Music of the Spheres.' Earth, too, like the planets, is a celestial body, moving like them around the central fire. [71] By analogy with this conception of the universe as the realisation of God, so also the body, whether [72] of man or of any creature, is the realisation for the time being of a soul. Without the body and the life of the body, that soul were a blind and fleeting ghost. Of such unrealised souls there are many in various degrees and states; the whole air indeed is full of spirits, who are the causes of dreams and omens. [73] Thus the change and flux that are visible in all else are visible also in the relations of soul and body. Multitudes of fleeting ghosts or spirits are continually seeking realisation through union with bodies, passing at birth into this one and that, and at death issuing forth again into the void. Like wax which takes now one impression now another, yet remains in itself ever the same, so souls vary in the outward {28} [74] form that envelops and realises them. In this bodily life, the Pythagoreans are elsewhere described as saying, we are as it were in bonds or in a prison, whence we may not justly go forth till the Lord calls us. This idea Cicero mistranslated with a truly Roman fitness: according to him they taught that in this life we are as sentinels at our post, who may not quit it till our Commander orders.