Whether There Is Only One World?
Objection 1: It would seem that there is not only one world, but many.
Because, as Augustine says (QQ. 83, qu. 46), it is unfitting to say
that God has created things without a reason. But for the same reason
He created one, He could create many, since His power is not limited
to the creation of one world; but rather it is infinite, as was shown
above (Q. 25, A. 2). Therefore God has produced many worlds.
Obj. 2: Further, nature does what is best and much more does God.
But it is better for there to be many worlds than one, because many
good things are better than a few. Therefore many worlds have been
made by God.
Obj. 3: Further, everything which has a form in matter can be
multiplied in number, the species remaining the same, because
multiplication in number comes from matter. But the world has a form
in matter. Thus as when I say "man" I mean the form, and when I say
"this man," I mean the form in matter; so when we say "world," the
form is signified, and when we say "this world," the form in the
matter is signified. Therefore there is nothing to prevent the
existence of many worlds.
_On the contrary,_ It is said (John 1:10): "The world was made by
Him," where the world is named as one, as if only one existed.
_I answer that,_ The very order of things created by God shows the
unity of the world. For this world is called one by the unity of
order, whereby some things are ordered to others. But whatever things
come from God, have relation of order to each other, and to God
Himself, as shown above (Q. 11, A. 3; Q. 21, A. 1). Hence it must be
that all things should belong to one world. Therefore those only can
assert that many worlds exist who do not acknowledge any ordaining
wisdom, but rather believe in chance, as Democritus, who said that
this world, besides an infinite number of other worlds, was made
from a casual concourse of atoms.
Reply Obj. 1: This reason proves that the world is one because all
things must be arranged in one order, and to one end. Therefore from
the unity of order in things Aristotle infers (Metaph. xii, text 52)
the unity of God governing all; and Plato (Tim.), from the unity of
the exemplar, proves the unity of the world, as the thing designed.
Reply Obj. 2: No agent intends material plurality as the end
forasmuch as material multitude has no certain limit, but of itself
tends to infinity, and the infinite is opposed to the notion of end.
Now when it is said that many worlds are better than one, this has
reference to material order. But the best in this sense is not the
intention of the divine agent; forasmuch as for the same reason it
might be said that if He had made two worlds, it would be better if
He had made three; and so on to infinite.
Reply Obj. 3: The world is composed of the whole of its matter. For
it is not possible for there to be another earth than this one, since
every earth would naturally be carried to this central one, wherever
it was. The same applies to the other bodies which are part of the
world.
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