The Complete Aristotle (eng.)

of
the place, and change in respect of ‘thisness’ is simple generation
and destruction, and change in quantity is increase and diminution,
and change in respect of an affection is alteration, and change of
place is motion, changes will be from given states into those
contrary to them in these several respects. The matter, then, which
changes must be capable of both states. And since that which ‘is’
has two senses, we must say that everything changes from that which
is potentially to that which is actually, e.g. from potentially
white to actually white, and similarly in the case of increase and
diminution. Therefore not only can a thing come to be,
incidentally, out of that which is not, but also all things come to
be out of that which is, but is potentially, and is not actually.
And this is the ‘One’ of Anaxagoras; for instead of ‘all things
were together’-and the ‘Mixture’ of Empedocles and Anaximander and
the account given by Democritus-it is better to say ‘all things
were together potentially but not actually’. Therefore these
thinkers seem to have had some notion of matter. Now all things
that change have matter, but different matter; and of eternal
things those which are not generable but are movable in space have
matter-not matter for generation, however, but for motion from one
place to another.
    One might raise the question from what sort of non-being
generation proceeds; for ‘non-being’ has three senses. If, then,
one form of non-being exists potentially, still it is not by virtue
of a potentiality for any and every thing, but different things
come from different things; nor is it satisfactory to say that ‘all
things were together’; for they differ in their matter, since
otherwise why did an infinity of things come to be, and not one
thing? For ‘reason’ is one, so that if matter also were one, that
must have come to be in actuality which the matter was in potency.
The causes and the principles, then, are three, two being the pair
of contraries of which one is definition and form and the other is
privation, and the third being the matter.
<
    div id="section133" class="section" title="3">
3
    Note, next, that neither the matter nor the form comes to be-and
I mean the last matter and form. For everything that changes is
something and is changed by something and into something. That by
which it is changed is the immediate mover; that which is changed,
the matter; that into which it is changed, the form. The process,
then, will go on to infinity, if not only the bronze comes to be
round but also the round or the bronze comes to be; therefore there
must be a stop.
    Note, next, that each substance comes into being out of
something that shares its name. (Natural objects and other things
both rank as substances.) For things come into being either by art
or by nature or by luck or by spontaneity. Now art is a principle
of movement in something other than the thing moved, nature is a
principle in the thing itself (for man begets man), and the other
causes are privations of these two.
    There are three kinds of substance-the matter, which is a ‘this’
in appearance (for all things that are characterized by contact and
not, by organic unity are matter and substratum, e.g. fire, flesh,
head; for these are all matter, and the last matter is the matter
of that which is in the full sense substance); the nature, which is
a ‘this’ or positive state towards which movement takes place; and
again, thirdly, the particular substance which is composed of these
two, e.g. Socrates or Callias. Now in some cases the ‘this’ does
not exist apart from the composite substance, e.g. the form of
house does not so exist, unless the art of building exists apart
(nor is there generation and destruction of these forms, but it is
in another way that the house apart from its matter, and health,
and all ideals of art, exist and do not exist); but if the ‘this’
exists apart from the concrete thing, it is only in the case of
natural objects. And so Plato was not far wrong when he said that
there are as many Forms as there are kinds of natural object (if
there are Forms distinct from the things of this earth). The moving
causes exist as things preceding the effects, but causes in the
sense of definitions are simultaneous with their effects. For when
a man is healthy, then health also exists; and the shape of a
bronze sphere exists at the same time as the bronze sphere. (But we
must examine whether any