PROCLUS ON THE TIMAEUS BOOK III [Tim. 31B]

...not leaving the region around the center; for if it moved, it would move in a circle. Indeed, whenever fire is carried upward, it is carried upward because it is in a foreign place, and a clod of earth is likewise carried downward; in general, the straight-line motions of the elements belong to those situated contrary to their nature. Proclus is following Aristotelian physics here: elements move in straight lines only to reach their "natural home." Once there, they either rest or move in circles. Thus, it is false to say that fire moves in a straight line according to its nature. For it possesses its nature most fully when it occupies its own proper place; but when it is being carried toward its proper place, it does not yet possess its natural state. This having been shown, it is clear how the celestial fire, since it moves, moves in a circle and in no way disturbs the Platonic account. For if it did not move in a circle original: μὴ κύκλῳ, the fire would not yet be in its natural place. But if it is in its natural place, it will either be motionless or move in a circle. However, it is impossible for it to be motionless, for all fire is by nature easily moved; therefore, it will move only in a circle. But let us return to the subject at hand.

F

If, then, the universe is generated, it must be sensible; and if it is sensible, it must be visible and tangible. If these things are so, it must be composed of fire and earth; and if of these, then also of the middle elements Air and water, which act as mathematical means between fire and earth.; for these [fire and earth] stand furthest apart from one another, just as touch and sight stand apart. If the world is visible, there must be fire; if it is tangible, there must be earth. For that which is solid is tangible, being that which is able to offer resistance to touch; for that which is easily broken and does not withstand touch is in no way tangible. For this reason, Pythagoras calls the earth "enduring" original: τλήμονα; a poetic epithet implying the earth's ability to support weight and resist pressure., as being solid and as resisting touch, and as being difficult to move and participating in a stable power.

143

If therefore, as has been said, there is a need for fire so that the world may be visible, and earth so that it may be tangible, God, beginning from fire and earth, will make the whole. This is not to say that God makes these things first in a sequence of time—for we have long ago rejected the idea of a generation according to time—but since every study of nature physiologia: the study of the internal workings of nature makes its beginning from opposites, for this reason he says the whole has begun its composition [from these].

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These are sigla referring to specific medieval manuscripts used by the editor to reconstruct the text.