Page:Mathematical collections and translations, in two tomes - Salusbury (1661).djvu/51

 incorruptible, unalterable, &c. and this corruptible, alterable, &c.

I see not yet any need that Aristotle hath of help, standing as he doth stoutly and strongly on his feet; yea not being yet assaulted, much less foiled by you. And what ward will you choose in this combate for this first blow? Aristotle writeth, that whatever is generated, is made out of a contrary in some subject, and likewise is corrupted in some certain subject from a contrary into a contrary; so that (observe) corruption and generation is never but onely in contraries; If therefore to a Cœlestial Body no contrary can be assigned, for that to the circular motion no other motion is contrary, then Nature hath done very well to make that exempt from contraries, which was to be ingenerable and incorruptible, This fundamental first confirmed, it immediately followeth of consequence, that it is inaugmentable, inalterable, impassible, and finally eternal, and a proportionate habitation to the immortal Deities, conformable to the opinion even of all men that have any conceit of the Gods. He afterwards confirmeth the same by sense; in regard, that in all times past, according to memory or tradition, we see nothing removed, according to the whole outward Heaven, nor any of its proper parts. Next, as to the circular motion, that no other is contrary to it, Aristotle proveth many ways; but without reciting them all, it is sufficiently demonstrated, since simple motions are but three, to the medium, from the medium, and about the medium, of which the two right, sursum and deorsum, are manifestly contrary; and because one onely hath onely one for contrary, therefore there rests no other motion which may be contrary to the circular. You see the subtle and most concluding discourse of Aristotle, whereby he proveth the incorruptibility of Heaven.

This is nothing more, save the pure progress of Aristotle, by me hinted before; wherein, besides that I affirm, that the motion which you attribute to the Cœlestial Bodies agreeth also to the Earth, its illation proves nothing. I tell you therefore, that that circular motion which you assign to Cœlestial Bodies, suiteth also to the Earth, from which, supposing that the rest of your discourse were concludent, will follow one of these three things, as I told you a little before, and shall repeat; namely, either that the Earth it self is also ingenerable, and incorruptible, as the Cœlestial bodies; or that the Cœlestial bodies are, like as the Elementary generable, alterable &c. or that this difference of motion hath nothing to do with Generation and Corruption. The discourse of Aristotle, and yours also contain many Propositions not to be lightly admitted, and the better to examine them, it will be convenient to reduce them to the most abstracted and