Of Violent motion2 Of Violent motion2 Of Violent motionOf Violent motionThe Newton Project Knowledge Graph2020-10-08Journal2 Of Violent motion
Therefore it must be moved after its seperation from the mover by it one gravity. Which will be cleare by seing whither there can be motion in a vacuum & what that motion is & so compareing it with motion in pleno.
1 That there may be motion in vacuo let us suppose (a b) to be a body as a peice of Aire (c. d. e.) to be three globes, (f g h i) & all the space about the globes & that aire to be inane now in the chapter de vacuo wee have shewed that those Figure three globes would be really seperate & not touch one another. you will grant that halfe the globes are in places & consequently may move, suppose then that halfe of (r) in the aire move towards (d) we aske whither that part in vacuo would move along with it or stay behind & be seperated frome it if the first we have our desire if the last wee ask what should seperate it from it not the vacuum since that is accounted nothing. but you may say that it is not truly motion for the upper parte of r to be carried to (d) we answer that where there is action (for such is the passing of (r) to (d)) & where there are new respects acquired to the same bodys there must be motion, but the upper part of (r) hath neither the same respect to the aire nor to (d) which it had before it began to pass towards d. If this going of r to d be not motion I aske what it is. but this is onely to strive about termes & if it please you not to call it motion cal it what you will but it is that which we aimed to prove & there is but this difference twixt it & motion in pleno. that the one is environed with such mater as is impenitrable & consequently that mater must be crouded out of the moving bodys way before or rather at the same time that the body moves, it must needs impede the motion to be continually thrusting against & resisted by the body before it: but in vacuo it meetes with nothing impenitrable to stay it tis true God is as far as vacuum extends but he being a spirit & penetrating all matter can be no obstacle to the motion of matter noe more than if nothing were in its way Let mee aske why one should be motion more than another since in pleno motion is so stopped by one body rubbing uppon another & in vacuum it hath its liberty can the same thing (viz a being invironed with bodys) at the same give a being to motion & yet destroy it, wherefore to be in pleno cannot be essentiall to motion. & if it were things would be more properly sade to move where there is most body or they find most resistance to theire motion & so more properly in water than in aire &c. But it is objected by Aristotle that a Vacuum is uniforme & every where alike & a body hath the same respects to a vacuum in all places alike but there is no motion with some mutation of circumstances And so in Vacuo no motion I answer as to our senses the aire is uniforme And we judge a thing to be moved when we se it come nigher or goe farther from some thing which our senses can perceive & so we judge not a thing to be moved in respect of the aire but of the earth or some thing