Page:Early Greek philosophy by John Burnet, 3rd edition, 1920.djvu/316

302 When, however, Boeckh goes on to argue that the word ἰλλομένην in the Timaeus does not refer to motion at all, but that it means "globed" or "packed" round, it is quite impossible for me to follow him. Apart from all philological considerations, this interpretation makes nonsense of Aristotle's line of argument. He says that, if the earth is in motion, whether "outside the centre" or "at the centre," that cannot be a "natural motion"; for, if it were, it would be shared by every particle of earth, and we see that the natural motion of every clod of earth is "down," i.e. towards the centre. He also says that, if the earth is in motion, whether "outside the centre" or "at the centre," it must have two motions like everything else but the "first sphere," and therefore there would be excursions in latitude (πάροδοι) and "turnings back" (τροπαί) of the fixed stars, which there are not. It is clear, then, that Aristotle regarded the second theory of the earth's movement as involving a motion of translation equally with the first, and that he supposed it to be the theory of Plato's Timaeus. It is impossible to believe that he can have been mistaken on such a point.

When we turn to the passage in the Timaeus itself, we find that, when the text is correctly established, it completely corroborates Aristotle's statement that a motion of translation is involved, and that Boeckh's rendering is inadmissible