attribute-plainly, I say, everything comes to be from both subject and
form. For 'musical man' is composed (in a way) of 'man' and 'musical':
you can analyse it into the definitions of its elements. It is clear
then that what comes to be will come to be from these elements.
Now the subject is one numerically, though it is two in form. (For
it is the man, the gold-the 'matter' generally-that is counted, for it
is more of the nature of a 'this', and what comes to be does not
come from it in virtue of a concomitant attribute; the privation, on
the other hand, and the contrary are incidental in the process.) And
the positive form is one-the order, the acquired art of music, or
any similar predicate.
There is a sense, therefore, in which we must declare the principles
to be two, and a sense in which they are three; a sense in which the
contraries are the principles-say for example the musical and the
unmusical, the hot and the cold, the tuned and the untuned-and a sense
in which they are not, since it is impossible for the contraries to be
acted on by each other. But this difficulty also is solved by the fact
that the substratum is different from the contraries, for it is itself
not a contrary. The principles therefore are, in a way, not more in
number than the contraries, but as it were two, nor yet precisely two,
since there is a difference of essential nature, but three. For 'to be
man' is different from 'to be unmusical', and 'to be unformed' from
'to be bronze'.
We have now stated the number of the principles of natural objects
which are subject to generation, and how the number is reached: and it
is clear that there must be a substratum for the contraries, and
that the contraries must be two. (Yet in another way of putting it
this is not necessary, as one of the contraries will serve to effect
the change by its successive absence and presence.)
The underlying nature is an object of scientific knowledge, by an
analogy. For as the bronze is to the statue, the wood to the bed, or
the matter and the formless before receiving form to any thing which
has form, so is the underlying nature to substance, i.e. the 'this' or
existent.
This then is one principle (though not one or existent in the same
sense as the 'this'), and the definition was one as we agreed; then
further there is its contrary, the privation. In what sense these
are two, and in what sense more, has been stated above. Briefly, we
explained first that only the contraries were principles, and later
that a substratum was indispensable, and that the principles were
three; our last statement has elucidated the difference between the
contraries, the mutual relation of the principles, and the nature of
the substratum. Whether the form or the substratum is the essential
nature of a physical object is not yet clear. But that the
principles are three, and in what sense, and the way in which each
is a principle, is clear.
So much then for the question of the number and the nature of the
principles.
8
We will now proceed to show that the difficulty of the early
thinkers, as well as our own, is solved in this way alone.
The first of those who studied science were misled in their search
for truth and the nature of things by their inexperience, which as
it were thrust them into another path. So they say that none of the
things that are either comes to be or passes out of existence, because
what comes to be must do so either from what is or from what is not,
both of which are impossible. For what is cannot come to be (because
it is already), and from what is not nothing could have come to be
(because something must be present as a substratum). So too they
exaggerated the consequence of this, and went so far as to deny even
the existence of a plurality of things, maintaining that only Being
itself is. Such then was their opinion, and such the reason for its
adoption.
Our explanation on the other hand is that the phrases 'something
does something or has something done to it or becomes some
particular thing', are to be taken (in the first way of putting our
explanation) in the same sense as 'a doctor does something or has
something done to him', 'is or becomes something from being a doctor.'
These expressions may be taken in two senses, and so too, clearly, may
'from being', and 'being acts or is acted on'. A doctor builds a
house, not qua doctor, but qua housebuilder, and turns gray, not qua
doctor, but qua dark-haired. On the other hand he doctors or fails
to doctor qua doctor. But we are using words most appropriately when
we say that a doctor does something or undergoes something, or becomes
something from being a doctor, if he does, undergoes, or becomes qua
doctor. Clearly then also 'to come to be so-and-so from not-being'
means 'qua not-being'.
It was through failure to make this distinction that those
thinkers gave the matter up, and through this error that they went
so much farther astray as to suppose that nothing else comes to be
or exists apart from Being itself, thus doing away with all becoming.
We ourselves are in agreement with them in holding that nothing
can be said without qualification to come from what is not. But
nevertheless we maintain that a thing may 'come to be from what is
not'-that is, in a qualified sense. For a thing comes to be from the
privation, which in its own nature is not-being,-this not surviving as
a constituent of the result. Yet this causes surprise, and it is
thought impossible that something should come to be in the way
described from what is not.
In the same way we maintain that nothing comes to be from being, and
that being does not come to be except in a qualified sense. In that
way, however, it does, just as animal might come to be from animal,
and an animal of a certain kind from an animal of a certain kind.
Thus, suppose a dog to come to be from a horse. The dog would then, it
is true, come to be from animal (as well as from an animal of a
certain kind) but not as animal, for that is already there. But if
anything is to become an animal, not in a qualified sense, it will not
be from animal: and if being, not from being-nor from not-being
either, for it has been explained that by 'from not being' we mean
from not-being qua not-being.
Note further that we do not subvert the principle that everything
either is or is not.
This then is one way of solving the difficulty. Another consists
in pointing out that the same things can be explained in terms of
potentiality and actuality. But this has been done with greater
precision elsewhere. So, as we said, the difficulties which
constrain people to deny the existence of some of the things we
mentioned are now solved. For it was this reason which also caused
some of the earlier thinkers to turn so far aside from the road
which leads to coming to be and passing aw
ay and change generally.
If they had come in sight of this nature, all their ignorance would
have been dispelled.
9
Others, indeed, have apprehended the nature in question, but not
adequately.
In the first place they allow that a thing may come to be without
qualification from not being, accepting on this point the statement of
Parmenides. Secondly, they think that if the substratum is one
numerically, it must have also only a single potentiality-which is a
very different thing.
Now we distinguish matter and privation, and hold that one of these,
namely the matter, is not-being only in virtue of an attribute which
it has, while the privation in its own nature is not-being; and that
the matter is nearly, in a sense is, substance, while the privation in
no sense is. They, on the other hand, identify their Great and Small
alike with not being, and that whether they are taken together as
one or separately. Their triad is therefore of quite a different
kind from ours. For they got so far as to see that there must be
some underlying nature, but they make it one-for even if one
philosopher makes a dyad of it, which he calls Great and Small, the
effect is the same, for he overlooked the other nature. For the one
which persists is a joint cause, with the form, of what comes to
be-a mother, as it were. But the negative part of the contrariety
may often seem, if you concentrate your attention on it as an evil
agent, not to exist at all.
For admitting with them that there is something divine, good, and
desirable, we hold that there are two other principles, the one
contrary to it, the other such as of its own nature to desire and
yearn for it. But the consequence of their view is that the contrary
desires its wtextinction. Yet the form cannot desire itself, for it is
not defective; nor can the contrary desire it, for contraries are
mutually destructive. The truth is that what desires the form is
matter, as the female desires the male and the ugly the beautiful-only
the ugly or the female not per se but per accidens.
The matter comes to be and ceases to be in one sense, while in
another it does not. As that which contains the privation, it ceases
to be in its own nature, for what ceases to be-the privation-is
contained within it. But as potentiality it does not cease to be in
its own nature, but is necessarily outside the sphere of becoming
and ceasing to be. For if it came to be, something must have existed
as a primary substratum from which it should come and which should
persist in it; but this is its own special nature, so that it will
be before coming to be. (For my definition of matter is just
this-the primary substratum of each thing, from which it comes to be
without qualification, and which persists in the result.) And if it
ceases to be it will pass into that at the last, so it will have
ceased to be before ceasing to be.
The accurate determination of the first principle in respect of
form, whether it is one or many and what it is or what they are, is
the province of the primary type of science; so these questions may
stand over till then. But of the natural, i.e. perishable, forms we
shall speak in the expositions which follow.
The above, then, may be taken as sufficient to establish that
there are principles and what they are and how many there are. Now let
us make a fresh start and proceed.
Book II
1
Of things that exist, some exist by nature, some from other causes.
'By nature' the animals and their parts exist, and the plants and
the simple bodies (earth, fire, air, water)-for we say that these
and the like exist 'by nature'.
All the things mentioned present a feature in which they differ from
things which are not constituted by nature. Each of them has within
itself a principle of motion and of stationariness (in respect of
place, or of growth and decrease, or by way of alteration). On the
other hand, a bed and a coat and anything else of that sort, qua
receiving these designations i.e. in so far as they are products of
art-have no innate impulse to change. But in so far as they happen
to be composed of stone or of earth or of a mixture of the two, they
do have such an impulse, and just to that extent which seems to
indicate that nature is a source or cause of being moved and of
being at rest in that to which it belongs primarily, in virtue of
itself and not in virtue of a concomitant attribute.
I say 'not in virtue of a concomitant attribute', because (for
instance) a man who is a doctor might cure himself. Nevertheless it is
not in so far as he is a patient that he possesses the art of
medicine: it merely has happened that the same man is doctor and
patient-and that is why these attributes are not always found
together. So it is with all other artificial products. None of them
has in itself the source of its own production. But while in some
cases (for instance houses and the other products of manual labour)
that principle is in something else external to the thing, in others
those which may cause a change in themselves in virtue of a
concomitant attribute-it lies in the things themselves (but not in
virtue of what they are).
'Nature' then is what has been stated. Things 'have a nature'which
have a principle of this kind. Each of them is a substance; for it
is a subject, and nature always implies a subject in which it inheres.
The term 'according to nature' is applied to all these things and
also to the attributes which belong to them in virtue of what they
are, for instance the property of fire to be carried upwards-which
is not a 'nature' nor 'has a nature' but is 'by nature' or
'according to nature'.
What nature is, then, and the meaning of the terms 'by nature' and
'according to nature', has been stated. That nature exists, it would
be absurd to try to prove; for it is obvious that there are many
things of this kind, and to prove what is obvious by what is not is
the mark of a man who is unable to distinguish what is self-evident
from what is not. (This state of mind is clearly possible. A man blind
from birth might reason about colours. Presumably therefore such
persons must be talking about words without any thought to
correspond.)
Some identify the nature or substance of a natural object with
that immediate constituent of it which taken by itself is without
arrangement, e.g. the wood is the 'nature' of the bed, and the
bronze the 'nature' of the statue.
As an indication of this Antiphon points out that if you planted a
bed and the rotting wood acquired the power of sending up a shoot,
it would not be a bed that would come up, but wood-which shows that
the arrangement in accordance with the rules of the art is merely an
incidental attribute, whereas the real nature is the other, which,
further, persists continuously through the process of making.
But if the material of each of these objects has itself the same
relation to something else, say bronze (or gold) to water, bones (or
wood) to earth and so on, that (they say) would be their nature and
essence. Consequently some assert earth, others fire or air or water
or some or all of these, to be the nature of the things that are.
For whatever any one of them supposed to have this character-whether
one thing or more than one thing-this or these he declared to be the
whole of substance, all else being its affections, states, or
dispositions. Every such thing they held to be eternal (for it could
not pass into anything else), but other things to come into being
and cease to be times without number.
This then is one account of 'nature', namely that it is the
immediate material substratum of things which have in themselves a
principle of motion or change.
Another account is that 'nature' is the shape or form which is
specified in the definition of the thing.
For the word 'nature' is applied to what is according to nature
and the natural in the same way as 'art' is applied to what is
artistic or a work of art. We should not say in the latter case that
there is anything artistic about a thing, if it is a bed only
potentially, not yet having the form of a bed; nor should we call it a
work of art. The same is true of natural compounds. What is
potentially flesh or bone has not yet its own 'nature', and does not
exist until it receives the form specified in the definition, which we
name in defining what flesh or bone is. Thus in the second sense of
'nature' it would be the shape or form (not separable except in
statement) of things which have in themselves a source of motion. (The
combination of the two, e.g. man, is not 'nature' but 'by nature' or
'natural'.)
The form indeed is 'nature' rather than the matter; for a thing is
more properly said to be what it is when it has attained to fulfilment