Book VIII
1
We must reckon up the
results arising from what has been said, and compute the sum of them,
and put the finishing touch to our inquiry. We have said that the
causes, principles, and elements of substances are the object of our
search.
And some substances are recognized by every one, but some have been
advocated by particular schools.
Those generally recognized are the natural substances, i.e. fire, earth,
water, air, &c., the simple bodies; second plants and their parts,
and animals and the parts of animals; and finally the physical universe
and its parts; while some particular schools say that Forms and the
objects of mathematics are substances. But there are arguments which
lead to the conclusion that there are other substances, the essence and
the substratum. Again, in another way the genus seems more
substantial than the various species, and the universal than the
particulars. And with the universal and the genus the Ideas are
connected; it is in virtue of the same argument that they are thought to
be substances. And since the essence is substance, and the definition is
a formula of the essence, for this reason we have discussed definition
and essential predication. Since the definition is a formula, and a
formula has parts, we had to consider also with respect to the notion of
'part', what are parts of the substance and what are not, and whether
the parts of the substance are also parts of the definition. Further,
too, neither the universal nor the genus is a substance; we must inquire
later into the Ideas and the objects of mathematics; for some say these
are substances as well as the sensible substances.
But now let us resume the discussion of the generally
recognized substances. These are the sensible substances, and sensible
substances all have matter. The substratum is substance, and this is in
one sense the matter (and by matter I mean that which, not being a
'this' actually, is potentially a 'this'), and in another sense the
formula or shape (that which being a 'this' can be separately
formulated), and thirdly the complex of these two, which alone is
generated and destroyed, and is, without qualification, capable of
separate existence; for of substances completely expressible in a
formula some are separable and some are separable and some are not.
But clearly matter also is substance; for in all the
opposite changes that occur there is something which underlies the
changes, e.g. in respect of place that which is now here and again
elsewhere, and in respect of increase that which is now of one size and
again less or greater, and in respect of alteration that which is now
healthy and again diseased; and similarly in respect of substance there
is something that is now being generated and again being destroyed, and
now underlies the process as a 'this' and again underlies it in respect
of a privation of positive character. And in this change the others are
involved. But in either one or two of the others this is not involved;
for it is not necessary if a thing has matter for change of place that
it should also have matter for generation and destruction.
The difference between becoming in the full sense and
becoming in a qualified sense has been stated in our physical works.
2
Since the substance
which exists as underlying and as matter is generally recognized, and
this that which exists potentially, it remains for us to say what is the
substance, in the sense of actuality, of sensible things. Democritus
seems to think there are three kinds of difference between things; the
underlying body, the matter, is one and the same, but they differ either
in rhythm, i.e. shape, or in turning, i.e. position, or in
inter-contact, i.e. order. But evidently there are many differences; for
instance, some things are characterized by the mode of composition of
their matter, e.g. the things formed by blending, such as honey-water;
and others by being bound together, e.g. bundle; and others by being
glued together, e.g. a book; and others by being nailed together, e.g. a
casket; and others in more than one of these ways; and others by
position, e.g.
threshold and lintel (for these differ by being placed in a certain
way); and others by time, e.g. dinner and breakfast; and others by
place, e.g. the winds; and others by the affections proper to sensible
things, e.g. hardness and softness, density and rarity, dryness and
wetness; and some things by some of these qualities, others by them all,
and in general some by excess and some by defect. Clearly, then, the
word 'is' has just as many meanings; a thing is a threshold because it
lies in such and such a position, and its being means its lying in that
position, while being ice means having been solidified in such and such
a way. And the being of some things will be defined by all these
qualities, because some parts of them are mixed, others are blended,
others are bound together, others are solidified, and others use the
other differentiae; e.g. the hand or
the foot requires such complex definition. We must grasp, then, the
kinds of differentiae (for these will be the principles of the being of
things), e.g. the things characterized by the more and the less, or by
the dense and the rare, and by other such qualities; for all these are
forms of excess and defect. And anything that is characterized by shape
or by smoothness and roughness is characterized by the straight and the
curved. And for other things their being will mean their being mixed,
and their not being will mean the opposite.
It is clear, then, from these facts that, since its
substance is the cause of each thing's being, we must seek in these
differentiae what is the cause of the being of each of these things. Now
none of these differentiae is substance, even when coupled with matter,
yet it is what is analogous to substance in each case; and as in
substances that which is predicated of the matter is the actuality
itself, in all other definitions also it is what most resembles full
actuality. E.g. if we had to define a threshold, we should say 'wood or
stone in such and such a position', and a house we should define as
'bricks and timbers in such and such a position',(or a purpose may exist
as well in some cases), and if we had to define ice we should say 'water
frozen or solidified in such and such a way', and harmony is 'such and
such a blending of high and low'; and similarly in all other cases.
Obviously, then, the actuality or the formula is
different when the matter is different; for in some cases it is the
composition, in others the mixing, and in others some other of the
attributes we have named. And so, of the people who go in for defining,
those who define a house as stones, bricks, and timbers are speaking of
the potential house, for these are the matter; but those who propose 'a
receptacle to shelter chattels and living beings', or something of the
sort, speak of the actuality. Those who combine both of these speak of
the third kind of substance, which is composed of matter and form (for
the formula that gives the differentiae seems to be an account of the
form or actuality, while that which gives the components is rather an
account of the matter); and the same is true of the kind of definitions
which Archytas used to accept; they are accounts of the combined form
and matter. E.g. what is still weather? Absence of motion in a large
expanse of air; air is the matter, and absence of motion is the
actuality and substance.
What is a calm? Smoothness of sea; the material substratum is the sea,
and the actuality or shape is smoothness. It is obvious then, from what
has been said, what sensible substance is and how it exists-one kind of
it as matter, another as form or actuality, while the third kind is that
which is composed of these two.
3
We must not fail to
notice that sometimes it is not clear whether a name means the composite
substance, or the actuality or form, e.g. whether 'house' is a sign for
the composite thing, 'a covering consisting of bricks and stones laid
thus and thus', or for the actuality or form, 'a covering', and whether
a line is 'twoness in length' or 'twoness', and whether an animal is
soul in a body' or 'a soul'; for soul is the substance or actuality of
some body. 'Animal' might even be applied to both, not as something
definable by one formula, but as related to a single thing. But this
question, while important for another purpose, is of no importance for
the inquiry into sensible substance; for the essence certainly attaches
to the
form and the actuality. For 'soul' and 'to be soul' are the same, but
'to be man' and 'man' are not the same, unless even the bare soul is to
be called man; and thus on one interpretation the thing is the same as
its essence, and on another it is not.
If we examine we find that the syllable does not
consist of the letters + juxtaposition, nor is the house bricks +
juxtaposition. And this is right; for the juxtaposition or mixing does
not consist of those things of which it is the juxtaposition or mixing.
And the same is true in all other cases; e.g. if the threshold is
characterized by its position, the position is not constituted by the
threshold, but rather the latter is constituted by the former. Nor is
man animal + biped, but there must be something besides these, if these
are matter,-something which is neither an element in the whole nor a
compound, but is the substance; but this people eliminate, and state
only the matter. If, then, this is the cause of the thing's being, and
if the cause of its being is its substance, they will not be stating the
substance itself.
(This, then, must either be eternal or it must be
destructible without being ever in course of being destroyed, and must
have come to be without ever being in course of coming to be.
But it has been proved and explained elsewhere that no one makes or
begets the form, but it is the individual that is made, i.e. the complex
of form and matter that is generated. Whether the substances of
destructible things can exist apart, is not yet at all clear; except
that obviously this is impossible in some cases-in the case of things
which cannot exist apart from the individual instances, e.g. house or
utensil. Perhaps, indeed, neither these things themselves, nor any of
the other things which are not formed by nature, are substances at all;
for one might say that the nature in natural objects is the only
substance to be found in destructible things.)
Therefore the difficulty which used to be raised by
the school of Antisthenes and other such uneducated people has a certain
timeliness. They said that the 'what' cannot be defined (for the
definition so called is a 'long rigmarole') but of what sort a thing,
e.g. silver, is, they thought it possible actually to explain, not
saying what it is, but that it is like tin. Therefore one kind of
substance can be defined and formulated, i.e. the composite kind,
whether it be perceptible or intelligible; but the primary parts of
which this consists cannot be defined, since a definitory formula
predicates something of something, and one part of the definition must
play the part of matter and the other that of form.
It is also obvious that, if substances are in a sense
numbers, they are so in this sense and not, as some say, as numbers of
units. For a definition is a sort of number; for (1) it is divisible,
and into indivisible parts (for definitory formulae are not infinite),
and number also is of this nature. And (2) as, when one of the parts of
which a number consists has been taken from or added to the number, it
is no longer the same number, but a different one, even if it is the
very smallest part that has been taken away or added, so the definition
and the essence will no longer remain when anything has been taken away
or added. And (3) the number must be something in virtue of which it is
one, and this these thinkers cannot state, what makes it one, if it is
one (for either it is not one but a sort of heap, or if it is, we ought
to say what it is that makes one out of many); and the definition is
one, but similarly they cannot say what makes it one.
And this is a natural result; for the same reason is applicable, and
substance is one in the sense which we have explained, and not, as some
say, by being a sort of unit or point; each is a complete reality and a
definite nature. And (4) as number does not admit of the more and the
less, neither does substance, in the sense of form, but if any substance
does, it is only the substance which involves matter. Let this, then,
suffice for an account of the generation and destruction of so-called
substances in what sense it is possible and in what sense
impossible--and of the reduction of things to number.
4
Regarding material
substance we must not forget that even if all things come from the same
first cause or have the same things for their first causes, and if the
same matter serves as starting-point for their generation, yet there is
a matter proper to each, e.g. for phlegm the sweet or the fat, and for
bile the bitter, or something else; though perhaps these come from the
same original matter. And there come to be several matters for the same
thing, when the one matter is matter for the other; e.g. phlegm comes
from the fat and from the sweet, if the fat comes from the sweet; and it
comes from bile by analysis of the bile into its ultimate matter. For
one thing comes from another in two senses, either because it will be
found at a later stage, or because it is produced if the other is
analysed into its original constituents. When the matter is one,
different things may be produced owing to difference in the moving
cause; e.g. from wood may be made both a chest and a bed. But some
different things must have their matter different; e.g. a saw could not
be made of wood, nor is this in the power of the moving cause; for it
could not make a saw of wool or of wood. But if, as a matter of fact,
the same thing can be made of different material, clearly the art, i.e.
the moving principle, is the same; for if both the matter and the moving
cause were different, the product would be so too.
When one inquires into the cause of something, one
should, since 'causes' are spoken of in several senses, state all the
possible causes. what is the material cause of man? Shall we say 'the
menstrual fluid'? What is moving cause? Shall we say 'the seed'? The
formal cause? His essence. The final cause? His end.
But perhaps the latter two are the same.-It is the proximate causes we
must state. What is the material cause? We must name not fire or earth,
but the matter peculiar to the thing.
Regarding the substances that are natural and
generable, if the causes are really these and of this number and we have
to learn the causes, we must inquire thus, if we are to inquire rightly.
But in the case of natural but eternal substances another account must
be given. For perhaps some have no matter, or not matter of this sort
but only such as can be moved in respect of place. Nor does matter
belong to those things which exist by nature but are not substances;
their substratum is the substance. E.g what is the cause of eclipse?
What is its matter? There is none; the moon is that which suffers
eclipse. What is the moving cause which extinguished the light? The
earth. The final cause perhaps does not exist. The formal principle is
the definitory formula, but this is obscure if it does not include the
cause. E.g. what is eclipse? Deprivation of light. But if we add 'by the
earth's coming in between', this is the formula which includes the
cause. In the case of sleep it is not clear what it is that proximately
has this affection. Shall we say that it is the animal? Yes, but the
animal in virtue of what, i.e. what is the proximate subject? The heart
or some other part. Next, by what is it produced? Next, what is the
affection-that of the proximate subject, not of the whole animal?
Shall we say that it is immobility of such and such a kind? Yes, but to
what process in the proximate subject is this due?
5
Since some things are
and are not, without coming to be and ceasing to be, e.g. points, if
they can be said to be, and in
general forms (for it is not 'white' comes to be, but the wood comes to
be white, if everything that comes to be comes from something and comes
to be something), not all contraries can come from one another, but it
is in different senses that a pale man comes from a dark man, and pale
comes from dark.
Nor has everything matter, but only those things which come to be and
change into one another.
Those things which, without ever being in course of changing, are or are
not, have no matter.
There is difficulty in the question how the matter of
each thing is related to its contrary states. E.g. if the body is
potentially healthy, and disease is contrary to health, is it
potentially both healthy and diseased? And is water potentially wine and
vinegar? We answer that it is the matter of one in virtue of its
positive state and its form, and of the other in virtue of the privation
of its positive state and the corruption of it contrary to its nature.
It is also hard to say why wine is not said to be the matter of vinegar
nor potentially vinegar (though vinegar is produced from it), and why a
living man is not said to be potentially dead. In fact they are not, but
the corruptions in question are accidental, and it is the matter of the
animal that is itself in virtue of its corruption the potency and matter
of a corpse, and it is water that is the matter of vinegar. For the
corpse comes from the animal, and vinegar from wine, as night from day.
And all the things which change thus into one another must go back to
their matter; e.g. if from a corpse is produced an animal, the corpse
first goes back to its matter, and only then becomes an animal; and
vinegar first goes back to water, and only then becomes wine.
6
To return to the
difficulty which has been stated with respect both to definitions and to
numbers, what is the cause of their
unity? In the case of all things which have several parts and in which
the totality is not, as it were, a mere heap, but the whole is something
beside the parts, there is a cause; for even in bodies contact is the
cause of unity in some cases, and in others viscosity or some other such
quality. And a definition is a set of words which is one not by being
connected together, like the Iliad, but by dealing with one object.-What
then, is it that makes man one; why is he one and not many, e.g. animal
+ biped, especially if there are, as some say, an animal-itself and a
biped-itself? Why are not those Forms themselves the man, so that men
would exist by participation not in man, nor in-one Form, but in two,
animal and biped, and in general man
would be not one but more than one thing, animal and biped?
Clearly, then, if people proceed thus in their usual
manner of definition and speech, they cannot explain and solve the
difficulty. But if, as we say, one element is matter and another is
form, and one is potentially and the other actually, the question will
no longer be thought a difficulty. For this difficulty is the same as
would arise if 'round bronze' were the definition of 'cloak'; for this
word would be a sign of the definitory formula, so that the question is,
what is the cause of the unity of 'round' and 'bronze'? The difficulty
disappears, because the one is matter, the other form. What, then,
causes this-that which was potentially to be actually-except, in the
case of things which are generated, the agent? For there is no other
cause of the potential sphere's becoming actually a sphere, but this was
the essence of either. Of matter some is intelligible, some perceptible,
and in a formula there is always an element of matter as well as one of
actuality; e.g. the circle is 'a plane figure'. But of the things which
have no matter, either intelligible or perceptible, each is by its
nature essentially a kind of unity, as it is essentially a kind of
being-individual substance, quality, or quantity (and so neither
'existent' nor 'one' is present in their definitions), and the essence
of each of them is by its very nature a kind of unity as it is a kind of
being-and so none of these has any reason outside itself, for being one,
nor for being a kind of being; for each is by its nature a kind of being
and a kind of unity, not as being in the genus 'being' or 'one' nor in
the sense that being and unity can exist apart from particulars.
Owing to the difficulty about unity some speak of
'participation', and raise the question, what is the cause of
participation and what is it to participate; and others speak of
'communion', as Lycophron says knowledge is a communion of knowing with
the soul; and others say life is a 'composition' or 'connexion' of soul
with body. Yet the same account applies to all cases; for being healthy,
too, will on this showing be either a 'communion' or a 'connexion' or a
'composition' of soul and health, and the fact that the bronze is a
triangle will be a 'composition' of bronze and triangle, and the fact
that a thing is white will be a 'composition' of surface and whiteness.
The reason is that people look for a unifying formula, and a difference,
between potency and complete reality. But, as has been said, the
proximate matter and the form are one and the same thing, the one
potentially, and the other actually. Therefore it is like asking what in
general is the cause of unity and of a thing's being one; for each thing
is a unity, and the potential and the actual are somehow one. Therefore
there is no other cause here unless there is something which caused the
movement from potency into actuality. And all things which have no
matter are without qualification essentially unities.
|
