Plato’s Timaeus. Folio VII.

The globe of the world was made so that it might act and likewise suffer all things, with its parts acting and suffering within itself. Indeed, he The Demiurge or Creator did not deem hands necessary for it, since there was nothing outside to be grasped. † Small compartments Nor did it need feet, since of the seven types of motion, the one that suited it was not local movement, but rather the rational motion which is the proper circuit of souls. It does not change from one place to another; therefore, it is borne in a circle and flies around as if on a fixed axis: for this reason, its agitation is constant and unerring. This foresight of the eternal God, regarding the god that was born and would ever be The physical Universe, produced it as smooth, even, and unswerving, equal in every direction from its center, a whole and perfect being made from perfect and universal parts. He placed the Soul in its center and commanded it to be stretched equally through the entire globe: so that while the inner parts were covered, the outermost parts of the entire body would also be surrounded by the circuit of the soul. And so he willed a smooth sphere to be contained and moved within a sphere and within its own circuit. He created it solitary, yet sufficient in the excellence of its virtues for its own companionship, needing no outside help, always a friend to itself: and therefore he begot it as supremely blessed and endowed with divine power. However, God did not grant the origin of the soul in the same order in which we are currently speaking; he did not make it younger than or posterior to the body. E For it was not fitting for an older thing to be ruled by one born later. But it is the habit of men to speak haphazardly, backwards, and without observing the proper order. In truth, God commanded the soul to precede the body’s nature in both antiquity and virtue: he willed it to be the mistress and to hold the right of command over that which it protects.

F And so he devised a third kind of soul. In this manner: from the indivisible substance that always remains in its own state, and again from that other substance which is the inseparable companion of bodies and is thought to be divided among those same bodies, he placed a third, mixed kind of substance in the middle between both. In the same way, from a twin and biform nature—one part of which is called "the Same" and the other "the Different"—he devised a third kind of nature: which he placed in the middle between the indivisible substance and that which is divided in corporeal union. He mixed all three of these into one form, even though that "Different" nature resisted the thickening and unification of the kinds. G When these were mixed with the substance and reduced from three into one, he again divided this whole one into appropriate parts: so that each part consisted of the substance of the "Different" and likewise of that which is called "the Same" from the twin nature, continuing the division this far. First, he took one portion from the whole; after that, a second portion double the first. H The third was one-and-a-half times the second, but triple the first. The fourth he took as double the second. The fifth was triple the third. The sixth was an assumption seven times greater than the first. The seventh was twenty-six parts larger than the first. I Having divided these in sequence, he then filled the intervals of double and triple quantity by cutting parts from the whole even now: and from these parts, he filled the spaces of the intervals, so that each interval was supported by two means Mathematical means, likely the harmonic and arithmetic. Furthermore, one of the means exceeded one extreme limit by the same proportion that it was exceeded by the other extreme limit. The other mean exceeded and was exceeded by the extremes by an equal sum and number. k Thus, when the limits of the "one-and-a-halfs" original: ἡμιόλιον (hemiolion) - a 3:2 ratio were born, and likewise those which exceed by a third part original: ἐπίτριτον (epitriton) - a 4:3 ratio, he filled the intervals of all the "four-thirds" with the spaces of the "nine-eighths" term: epogdoi - the 9:8 ratio, representing a whole tone in music from these connections: so that for a perfect and heaped completion, something was lacking from the "four-third," specifically as much as is lacking when a comparison is made...