|Galilei, Galileo Dialogues on two world systems 1661, tr. Salusbury, Thomas|
nothing against one that should affirm, that the principle of the cir
cular motions of grave and light bodies is an intern accident: I
know not how he may prove, that it cannot be a substance.
SIMP. He brings many Arguments against this. The first of
which is in these words: Si secundum (nempè, si dieas tale princi
pium esse substantiam) illud est aut materia, aut forma, aut compo
situm. Sed repugnant iterum tot diversæ rerum naturæ, quales
sunt aves, limaces, saxa, sagittæ, nives, fumi, grandines, pisces,
&c. quæ tamen omnia specie & genere differentia, moverentur à
naturâ suâ circulariter, ipsa naturis diversissima, &c. [In English
thus] If the second, (that is, if you shall say that this principle is
a substance) it is either matter, or form, or a compound of both.
But such diverse natures of things are again repugnant, such as are
birds, snails, stones, darts, snows, smoaks, hails, fishes, &c. all
which notwithstanding their differences in species and kind, are
moved of their own nature circularly, they being of their natures
most different, &c.
SALV. If these things before named are of diverse natures, and
things of diverse natures cannot have a motion in common, it must
follow, if you would give satisfaction to all, that you are to think
of, more than two motions onely of upwards and downwards: and
if there must be one for the arrows, another for the snails, another
for the stones, and another for fishes; then are you to bethink your
self of worms, topazes and mushrums, which are not less different
in nature from one another, than snow and hail.
SIMP. It seems that you make a jest of these Arguments.
SALV. No indeed, Simplicius, but it hath been already an
swered above, to wit, that if one motion, whether downwards or
upwards, can agree with all those things afore named, a circular
motion may no less agree with them: and as you are a Peripate
tick, do not you put a greater difference between an elementary
comet and a celeftial star, than between a fish and a bird? and
yet both those move circularly. Now propose your second Ar
SIMP. Si terra staret per voluntatem Dei, rotaréntne cætera, an
non? si hoc, falsum est à naturâ gyrare; si illud, redeunt priores
quæstiones. Et sanè mirum esset, quòd Gavia pisciculo, Alauda
nidulo suo, & corvus limaci, petraque, etiam volans, imminere
non posset. [Which I thus render:] If the Earth be supposed to
stand still by the will of God, should the rest of bodies turn round
or no? If not, then it's false that they are revolved by nature; if
the other, the former questions will return upon us. And
truly it would be strange that the Sea-pie should not be able to
hover over the small fish, the Lark over her nest, and the Crow o
ver the snail and rock, though flying.