is probable that the Earth of that other World would fall downe to this Center, and so mutually the aire and fire here ascend to those Regions in the other, which must needes much derogate from the providence of nature, and cause a great disorder in his workes. To this I answere, that if you will consider the nature of gravity, you will plainely see there is no ground to feare any such confusion, for heavinesse is nothing else but such a quality as causes a propension in its subject to tend downwards towards its owne Centre, so that for some of that earth to come hither would not bee said a fall but an ascension, since it moved from its owne place, and this would bee impossible (saith Ruvi) ) because against nature[1], and therefore no more to bee feared than the falling of the Heavens.
