Page:Mathematical collections and translations, in two tomes - Salusbury (1661).djvu/124

 by France, Spain, Italy, and sail to Aleppo, which London, France, Spain &c. stand still, not moving with the ship: but as to the Chests, Bales and other Parcels, wherewith the ship is stow'd and and laden, and in respect of the ship it self, the Motion from London to Syria is as much as nothing; and nothing-altereth the relation which is between them: and this, because it is common to all, and is participated by all alike: and of the Cargo which is in the ship, if a Bale were romag'd from a Chest but one inch onely, this alone would be in that Cargo, a greater Motion in respect of the Chest, than the whole Voyage of above three thousand miles, made by them as they were stived together.

This Doctrine is good, sound, and altogether Peripatetick.

I hold it to be much more antient: and suspect that Aristotle in receiving it from some good School, did not fully understand it, and that therefore, having delivered it with some alteration, it hath been an occasion of confusion amongst those, who would defend whatever he saith. And when he writ, that whatsoever moveth, doth move upon something immoveable, I suppose that he equivocated, and meant, that whatever moveth, moveth in respect to something immoveable; which proposition admitteth no doubt, and the other many.

Pray you make no digression, but proceed in the dissertation you began.

It being therefore manifest, that the motion which is common to many moveables, is idle, and as it were, null as to the relation of those moveables between themselves, because that among themselves they have made no change: and that it is operative onely in the relation that those moveables have to other things, which want that motion, among which the habitude is changed: and we having divided the Universe into two parts, one of which is necessarily moveable, and the other immoveable; for the obtaining of whatsoever may depend upon, or be required from such a motion, it may as well be done by making the Earth alone, as by making all the rest of the World to move: for that the operation of such a motion consists in nothing else, save in the relation or habitude which is between the Cœlestial Bodies, and the Earth, the which relation is all that is changed. Now if for the obtaining of the same effect ad unguem, it be all one whether the Earth alone moveth, the rest of the Universe standing still; or that, the Earth onely standing still, the whole Universe moveth with one and the same motion; who would believe, that Nature (which by common consent, doth not that by many things, which may be done by few) hath chosen to make an innumerable number of most vast bodies move, and that with an unconceivable