concerning the right that fire has to pass for the proper and
Universal Instrument of Analysing mixt Bodies, not to Anticipate that,
I say, if I were dispos'd to wrangle, I might alledge, that by
_Themistius_ his Experiment it would appear rather that those he calls
Elements, are made of those he calls mixt Bodies, then mix'd Bodies of
the Elements. For in _Themistius's_ Analyz'd Wood, and in other Bodies
dissipated and alter'd by the fire, it appears, and he confesses, that
which he takes for Elementary Fire and Water, are made out of the
Concrete; but it appears not that the Concrete was made up of Fire and
Water. Nor has either He, or any Man, for ought I know, of his
perswasion, yet prov'd that nothing can be obtained from a Body by the
fire that was not _Pre-existent_ in it.
At this unexpected objection, not only _Themistius_, but the rest of
the company appear'd not a little surpriz'd; but after a while
_Philoponus_ conceiving his opinion, as well as that of _Aristotle_,
concern'd in that Objection, You cannot sure (sayes he to
_Carneades_) propose this Difficulty; not to call it Cavill, otherwise
then as an Exercise of wit, and not as laying any weight upon it. For
how can that be separated from a thing that was not existent in it.
When, for instance, a Refiner mingles Gold and Lead, and exposing this
Mixture upon a Cuppell to the violence of the fire, thereby separates
it into pure and refulgent Gold and Lead (which driven off together
with the Dross of the Gold is thence call'd _Lithargyrium Auri_) can
any man doubt that sees these two so differing substances separated
from the Mass, that they were existent in it before it was committed
to the fire.
I should (replies _Carneades_) allow your Argument to prove something,
if, as Men see the Refiners commonly take before hand both Lead and
Gold to make the Mass you speak of, so we did see Nature pull down a
parcell of the Element of Fire, that is fancy'd to be plac'd I know
not how many thousand Leagues off, contiguous to the Orb of the Moon,
and to blend it with a quantity of each of the three other Elements,
to compose every mixt Body, upon whose Resolution the Fire presents
us with Fire, and Earth, and the rest. And let me add, _Philoponus_,
that to make your Reasoning cogent, it must be first prov'd, that the
fire do's only take the Elementary Ingredients asunder, without
otherwise altering them. For else 'tis obvious, that Bodies may afford
substances which were not pre-existent in them; as Flesh too long kept
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