XXXIT PHILOSOPHICAL SOCIETY OF WASHINGTON. 
things are to be conceived as a perpetual flux, resulting from the 
changing permutations and combinations of the indestructible atoms 
composing the eternal substrate of nature. And ‘thus it was that 
the doctrine of ultimate atoms, incessantly modified in the forms of 
their combination, but remaining forever the same in substance, 
became the legitimate deduction and the crowning corollary of the 
primal eldest maxim of physical philosophy. Aristotle expressly 
gives this genesis of the Atomic Philosophy of Greece in its reduc- 
tion by Anaxagoras. After saying that Anaxagoras hypothesized 
an infinity of atoms, to explain the myriad varieties of nature, be- 
cause he wished to avoid the reproach of getting something out of 
nothing, Aristotle adds: “ From the fact that contraries are made out 
of each other, they must needs have previously existed in each other ; 
for if everything that becomes must needs come either from some- 
thing or from nothing, and if this latter alternative is impossible, 
(about which all who treat of nature are agreed in opinion,) then 
it only remains to infer that everything which becomes must have 
come from the things in which it pre-existed, though, on account of 
the smallness of their bulks, made out of things imperceptible to 
us.” * 
The Atomic Philosophy of the Greeks was, therefore, not a mere 
exhalation of the imagination, but a logical inference from the 
starting point and major premise of their natural metaphysics. The 
doctrine of ultimate atoms in nature was, indeed, the necessary com- 
plement and reconciliation of the conception that all things are in 
elemental stir, and that yet in this elemental stir there is no crea- 
tion of anything out of nothing and no annihilation of anything, 
but only composition, decomposition, and recomposition. 
It need not surprise us, therefore, to find that the doctrine of 
ultimate atoms in nature is a universal- form of thought among 
thinking men of all the most advanced races in antiquity. Into 
the hidden historic springs of the Atomic Philosophy, as formu- 
lated by the Greeks, it is not here proposed to enquire. Whether its 
* Aristotle: Naturalis Auscultatio, I, iv, 2, (Didot’s ed., vol. 2, p. 252.) 
Compare, also, Lucretius, De Rer. Nat., I, 543-545: 
—— ‘ Quoniam supra docui nil posse creari 
‘De nilo, neque quod genitum est ad nil revocari, 
Esse immortali primordia corpore debent.”’ = 
