METAPHYSICS(BOOKXII) 151
knowledge of all things, of the sort that some people say there is, he could not start out
already knowing anything.
And yet all learning is by means of things all or some of which are already
known, whether it is by means of demonstration or by way of definitions (for it is nec-
essary that one already know and be familiar with those things out of which the defini-
tion is made), and likewise with learning through examples. But if it happens to be
innate, it is surely a wonder how we fail to notice that we have the most powerful kind
of knowledge. Furthermore, in what way will one know what something is made of, and
how will it be evident? For this too contains an impasse: for one might dispute in the
same way as about some syllables. For some people say that zais made of s, d,and a,
while some others say that it is a distinct sound and not made of any familiar ones.
What’s more, how could someone know those things of which sense perception consists
if he did not have the sense capacity? And yet he must, if indeed the elements out of
which all things are made are the same, in just the way that composite sounds are made
of the elements that belong to them.
BOOKXII
- Now since there are three kinds of thinghood, two of them natural and one
motionless, about the latter one must explain that it is necessary for there to be some
everlasting motionless independent thing. For independent things are primary among
beings, and if they were all destructible, everything would be destructible; but it is
impossible for motion either to come into being or to be destroyed (since it always is),
and impossible too for time. For if there were no time, there could be no before and
after; and motion is continuous in just the way that time is, since time is either the same
as or some attribute of motion. But there is no continuous motion other than in place,
and among these, other than in a circle.
But surely if there is something capable of moving and producing things, but not
at work in any way, there will not be motion; for what has a potency admits of not
being at work. Therefore, there is no benefit even if we adopt everlasting independent
things, as do those who bring in the forms, unless there is in them some source capable
of producing change; moreover, even this is not enough, not even if there is another
independent thing besides the forms, since if it is not going to be at work, there will not
be motion. What’s more, it is not enough even if it will be at work, if the thinghood of
it is potency, for there would not be everlasting motion, since what has being in
potency admits of not being. Therefore it is necessary that there be a source of such a
kind that the thinghood of it is being-at-work.* On top of that, it is necessary that these
independent things be without material, for they must be everlasting, if indeed any-
thing else is everlasting. Therefore they are being-at-work.
*
all being is being-at-work, and that anything inert would cease to be. The primary sense of the word belongs
to activities that are not motions; examples of these are seeing, knowing, and happiness, each understood as
an ongoing state that is complete at every instant.”
993 a
30
10
10
20
5
1071 b
5
15