Plutarch discussing this point, affirmes that it is not necessary there should be the same meanes of growth and fructifying in both these worlds, since nature might in her policy finde out more wayes than one how to bring about the same effect. But however, he thinks it is probable that the Moone her selfe sendeth forth warme winds, and by the swiftnesse of her motion there should breathe out a sweet and comfortable ayre, pleasant dewes, and gentle moisture, which might serve for refreshing and nourishment of the inhabitants and plants in that other world.
But since they have all things alike with us, as sea and land, and vaporous ayre encompassing both, I should rather therefore thinke that nature there should use the same way of producing meteors as shee doth with us (and not by a motion as Plutarch supposes:) because shee doth not love to vary from her usuall operations without some extraordinary impediment, but still keepes her beaten path unlesse shee bee driven thence.
One argument whereby I shall manifest this truth, may bee taken from those new Stars which have appeared in divers ages of the world, and by their paralax have been discerned to have been above the Moone, such as was that in Cassiopeia, that in Sagittarius, with many others betwixt the Planets. Hipparchus in his time tooke especiall notice of such as these,1 and therefore fancied out such constellations in which to place the Starrs, shewing how many there were in every asterisme, that so afterwards, posterity might know whether there were any new Starre produced, or any old one missing. Now the nature of these Comets may probably manifest, that in this other world there are other meteors also; for these in all likelyhood are nothing else but such evaporations caused by the Sunne from the bodies of the Planets. I shall prove this by shewing the improbabilities and inconveniences of any other opinion.
For the better pursuite of this ‘tis in the first place requisite, that I deale with our chiefe adversary, Caesar la Galla, who doth most directly oppose that truth which is here to be proved. Hee endeavouring to confirme the incorruptibility of the Heavens, and being there to satisfie the argument which is taken from these Comets, He answers it thus: Aut argumentum desumptum ex paralaxi, non est efficax, aut si est efficax, eorum instrumentorum usum decipere, vel ratione astri, vel medii, vel distantiae, aut ergo erat in suprema parte aeris, aut si in coelo, tum forsan factum erat ex reflectione radiorum Saturni & Iovis, qui tunc in conjunctione fuerant. Either the argument from the paralax is not efficacious, or if it bee, yet the use of the instruments might deceive, either in regard of the star, or the medium, or the distance, and so this comet might be in the upper regions of the ayre; or if it were in the heavens, there it might be produced by the reflexion of the rayes from Saturne and Iupiter, who were then in conjunction. You see what shifts hee is driven to, how he runnes up and downe to many starting holes, that he may find some shelter, and in stead of the strength of reason, he answers with a multitude of words, thinking (as the Proverbe is) that hee may use haile, when hee hath no thunder. Nihil turpius (saith2 Seneca) dubio & incerto, pedem modo referente, modo producente. What can there be more unseemely in one that should bee a faire disputant, than to be now here, now there, and so uncertaine, that one cannot tell where to find him? Hee thinks that there are not Comets in the heavens, because there may bee many other reasons of such appearances; but what he knowes not; perhaps (hee sayes) that argument from the paralax is not sufficient,3 or if it be, then there may bee some deceit in the observation. To this I may safely say, that he may justly bee accounted a weake Mathematician who mistrusts the strength of this argument; nor can hee know much in Astronomy, who understands not the paralax, which is a foundation of that Science; and I am sure that hee is a timerous man, who dares not believe the frequent experience of his senses, or trust to a demonstration.
True indeed, I grant ‘tis possible, that the eye, the medium, and the distance may all deceive the beholder; but I would have him shew which of all these was likely to cause an error in this observation? Meerely to say they might be deceived, is no sufficient answer; for by this I might confute the positions of all Astronomers, and affirme the starres are hard by us, because ‘tis possible they may bee deceived in their observing distance. But I forbeare any further reply; my opinion is of that Treatise, that either it was set forth purposely to tempt a confutation, that hee might see the opinion of Galilaeus confirmed by others, or else it was invented with as much haste and negligence as it was printed, there being in it almost as many faults as lines.