On Generation and Corruption
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On Generation and Corruption.
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On Generation and Corruption
Written 350 B.C.E
Translated by H. H. Joachim
Our next task is to study coming-to-be and passing-away. We are to distinguish
the causes, and to state the definitions, of these processes considered
in general-as changes predicable uniformly of all the things that come-to-be
and pass-away by nature. Further, we are to study growth and 'alteration'.
We must inquire what each of them is; and whether 'alteration' is to be
identified with coming-to-be, or whether to these different names there
correspond two separate processes with distinct natures.
On this question, indeed, the early philosophers are divided. Some
of them assert that the so-called 'unqualified coming-to-be' is 'alteration',
while others maintain that 'alteration' and coming-to-be are distinct.
For those who say that the universe is one something (i.e. those who generate
all things out of one thing) are bound to assert that coming-to-be is 'alteration',
and that whatever 'comes-to-be' in the proper sense of the term is 'being
altered': but those who make the matter of things more than one must distinguish
coming-to-be from 'alteration'. To this latter class belong Empedocles,
Anaxagoras, and Leucippus. And yet Anaxagoras himself failed to understand
his own utterance. He says, at all events, that coming-to-be and passing-away
are the same as 'being altered':' yet, in common with other thinkers, he
affirms that the elements are many. Thus Empedocles holds that the corporeal
elements are four, while all the elements-including those which initiate
movement-are six in number; whereas Anaxagoras agrees with Leucippus and
Democritus that the elements are infinite.
(Anaxagoras posits as elements the 'homoeomeries', viz. bone, flesh,
marrow, and everything else which is such that part and whole are the same
in name and nature; while Democritus and Leucippus say that there are indivisible
bodies, infinite both in number and in the varieties of their shapes, of
which everything else is composed-the compounds differing one from another
according to the shapes, 'positions', and 'groupings' of their
For the views of the school of Anaxagoras seem diametrically opposed
to those of the followers of Empedocles. Empedocles says that Fire, Water,
Air, and Earth are four elements, and are thus 'simple' rather than flesh,
bone, and bodies which, like these, are 'homoeomeries'. But the followers
of Anaxagoras regard the 'homoeomeries' as 'simple' and elements, whilst
they affirm that Earth, Fire, Water, and Air are composite; for each of
these is (according to them) a 'common seminary' of all the
Those, then, who construct all things out of a single element,
must maintain that coming-tobe and passing-away are 'alteration'. For they
must affirm that the underlying something always remains identical and
one; and change of such a substratum is what we call 'altering' Those,
on the other hand, who make the ultimate kinds of things more than one,
must maintain that 'alteration' is distinct from coming-to-be: for coming-to-be
and passingaway result from the consilience and the dissolution of the
many kinds. That is why Empedocles too uses language to this effect, when
he says 'There is no coming-to-be of anything, but only a mingling and
a divorce of what has been mingled'. Thus it is clear (i) that to describe
coming-to-be and passing-away in these terms is in accordance with their
fundamental assumption, and (ii) that they do in fact so describe them:
nevertheless, they too must recognize 'alteration' as a fact distinct from
coming to-be, though it is impossible for them to do so consistently with
what they say.
That we are right in this criticism is easy to perceive. For 'alteration'
is a fact of observation. While the substance of the thing remains unchanged,
we see it 'altering' just as we see in it the changes of magnitude called
'growth' and 'diminution'. Nevertheless, the statements of those who posit
more 'original reals' than one make 'alteration' impossible. For 'alteration,
as we assert, takes place in respect to certain qualities: and these qualities
(I mean, e.g. hot-cold, white-black, dry-moist, soft-hard, and so forth)
are, all of them, differences characterizing the 'elements'. The actual
words of Empedocles may be quoted in illustration-
The sun everywhere bright to see, and hot,
The rain everywhere dark and cold; and he distinctively characterizes
his remaining elements in a similar manner. Since, therefore, it is not
possible for Fire to become Water, or Water to become Earth, neither will
it be possible for anything white to become black, or anything soft to
become hard; and the same argument applies to all the other qualities.
Yet this is what 'alteration' essentially is.
It follows, as an obvious corollary, that a single matter must
always be assumed as underlying the contrary 'poles' of any change whether
change of place, or growth and diminution, or 'alteration'; further, that
the being of this matter and the being of 'alteration' stand and fall together.
For if the change is 'alteration', then the substratum is a single element;
i.e. all things which admit of change into one another have a single matter.
And, conversely, if the substratum of the changing things is one, there
Empedocles, indeed, seems to contradict his own statements as well
as the observed facts. For he denies that any one of his elements comes-to-be
out of any other, insisting on the contrary that they are the things out
of which everything else comes-to-be; and yet (having brought the entirety
of existing things, except Strife, together into one) he maintains, simultaneously
with this denial, that each thing once more comes-to-be out of the One.
Hence it was clearly out of a One that this came-to-be Water, and that
Fire, various portions of it being separated off by certain characteristic
differences or qualities-as indeed he calls the sun 'white and hot', and
the earth 'heavy and hard'. If, therefore, these characteristic differences
be taken away (for they can be taken away, since they came-to-be), it will
clearly be inevitable for Earth to come to-be out of Water and Water out
of Earth, and for each of the other elements to undergo a similar transformation-not
only then, but also now-if, and because, they change their qualities. And,
to judge by what he says, the qualities are such that they can be 'attached'
to things and can again be 'separated' from them, especially since Strife
and Love are still fighting with one another for the mastery. It was owing
to this same conflict that the elements were generated from a One at the
former period. I say 'generated', for presumably Fire, Earth, and Water
had no distinctive existence at all while merged in
There is another obscurity in the theory Empedocles. Are we to
regard the One as his 'original real'? Or is it the Many-i.e. Fire and
Earth, and the bodies co-ordinate with these? For the One is an 'element'
in so far as it underlies the process as matter-as that out of which Earth
and Fire come-to-be through a change of qualities due to 'the motion'.
On the other hand, in so far as the One results from composition (by a
consilience of the Many), whereas they result from disintegration the Many
are more 'elementary' than the One, and prior to it in their
We have therefore to discuss the whole subject of 'unqualified'
coming-to-be and passingaway; we have to inquire whether these changes
do or do not occur and, if they occur, to explain the precise conditions
of their occurrence. We must also discuss the remaining forms of change,
viz. growth and 'alteration'. For though, no doubt, Plato investigated
the conditions under which things come-to-be and pass-away, he confined
his inquiry to these changes; and he discussed not all coming-to-be, but
only that of the elements. He asked no questions as to how flesh or bones,
or any of the other similar compound things, come-to-be; nor again did
he examine the conditions under which 'alteration' or growth are attributable
A similar criticism applies to all our predecessors with the single
exception of Democritus. Not one of them penetrated below the surface or
made a thorough examination of a single one of the problems. Democritus,
however, does seem not only to have thought carefully about all the problems,
but also to be distinguished from the outset by his method. For, as we
are saying, none of the other philosophers made any definite statement
about growth, except such as any amateur might have made. They said that
things grow 'by the accession of like to like', but they did not proceed
to explain the manner of this accession. Nor did they give any account
of 'combination': and they neglected almost every single one of the remaining
problems, offering no explanation, e.g. of 'action' or 'passion' how in
physical actions one thing acts and the other undergoes action. Democritus
and Leucippus, however, postulate the 'figures', and make 'alteration'
and coming-to-be result from them. They explain coming-to-be and passing-away
by their 'dissociation' and 'association', but 'alteration' by their 'grouping'
and 'Position'. And since they thought that the 'truth lay in the appearance,
and the appearances are conflicting and infinitely many, they made the
'figures' infinite in number. Hence-owing to the changes of the compound-the
same thing seems different and conflicting to different people: it is 'transposed'
by a small additional ingredient, and appears utterly other by the 'transposition'
of a single constituent. For Tragedy and Comedy are both composed of the
Since almost all our predecessors think (i) that coming-to-be is
distinct from 'alteration', and (ii) that, whereas things 'alter' by change
of their qualities, it is by 'association' and 'dissociation' that they
come-to-be and pass-away, we must concentrate our attention on these theses.
For they lead to many perplexing and well-grounded dilemmas. If, on the
one hand, coming-to-be is 'association', many impossible consequences result:
and yet there are other arguments, not easy to unravel, which force the
conclusion upon us that coming-to-be cannot possibly be anything else.
If, on the other hand, coming-to-be is not 'association', either there
is no such thing as coming-to-be at all or it is 'alteration': or else
we must endeavour to unravel this dilemma too-and a stubborn one we shall
find it. The fundamental question, in dealing with all these difficulties,
is this: 'Do things come-to-be and "alter" and grow, and undergo the contrary
changes, because the primary "reals" are indivisible magnitudes? Or is
no magnitude indivisible?' For the answer we give to this question makes
the greatest difference. And again, if the primary 'reals' are indivisible
magnitudes, are these bodies, as Democritus and Leucippus maintain? Or
are they planes, as is asserted in the Timaeus?
To resolve bodies into planes and no further-this, as we have also
remarked elsewhere, in itself a paradox. Hence there is more to be said
for the view that there are indivisible bodies. Yet even these involve
much of paradox. Still, as we have said, it is possible to construct 'alteration'
and coming-to-be with them, if one 'transposes' the same by 'turning' and
'intercontact', and by 'the varieties of the figures', as Democritus does.
(His denial of the reality of colour is a corollary from this position:
for, according to him, things get coloured by 'turning' of the 'figures'.)
But the possibility of such a construction no longer exists for those who
divide bodies into planes. For nothing except solids results from putting
planes together: they do not even attempt to generate any quality from
Lack of experience diminishes our power of taking a comprehensive
view of the admitted facts. Hence those who dwell in intimate association
with nature and its phenomena grow more and more able to formulate, as
the foundations of their theories, principles such as to admit of a wide
and coherent development: while those whom devotion to abstract discussions
has rendered unobservant of the facts are too ready to dogmatize on the
basis of a few observations. The rival treatments of the subject now before
us will serve to illustrate how great is the difference between a 'scientific'
and a 'dialectical' method of inquiry. For, whereas the Platonists argue
that there must be atomic magnitudes 'because otherwise "The Triangle"
will be more than one', Democritus would appear to have been convinced
by arguments appropriate to the subject, i.e. drawn from the science of
nature. Our meaning will become clear as we proceed. For to suppose that
a body (i.e. a magnitude) is divisible through and through, and that this
division is possible, involves a difficulty. What will there be in the
body which escapes the division?
If it is divisible through and through, and if this division is
possible, then it might be, at one and the same moment, divided through
and through, even though the dividings had not been effected simultaneously:
and the actual occurrence of this result would involve no impossibility.
Hence the same principle will apply whenever a body is by nature divisible
through and through, whether by bisection, or generally by any method whatever:
nothing impossible will have resulted if it has actually been divided-not
even if it has been divided into innumerable parts, themselves divided
innumerable times. Nothing impossible will have resulted, though perhaps
nobody in fact could so divide it.
Since, therefore, the be dy is divisible through and through, let
it have been divided. What, then, will remain? A magnitude? No: that is
impossible, since then there will be something not divided, whereas ex
hypothesis the body was divisible through and through. But if it be admitted
that neither a body nor a magnitude will remain, and yet division is to
take place, the constituents of the body will either be points (i.e. without
magnitude) or absolutely nothing. If its constituents are nothings, then
it might both come-to-be out of nothings and exist as a composite of nothings:
and thus presumably the whole body will be nothing but an appearance. But
if it consists of points, a similar absurdity will result: it will not
possess any magnitude. For when the points were in contact and coincided
to form a single magnitude, they did not make the whole any bigger (since,
when the body was divided into two or more parts, the whole was not a bit
smaller or bigger than it was before the division): hence, even if all
the points be put together, they will not make any magnitude.
But suppose that, as the body is being divided, a minute section-a
piece of sawdust, as it were-is extracted, and that in this sense-a body
'comes away' from the magnitude, evading the division. Even then the same
argument applies. For in what sense is that section divisible? But if what
'came away' was not a body but a separable form or quality, and if the
magnitude is 'points or contacts thus qualified': it is paradoxical that
a magnitude should consist of elements, which are not magnitudes. Moreover,
where will the points be? And are they motionless or moving? And every
contact is always a contact of two somethings, i.e. there is always something
besides the contact or the division or the point.
These, then, are the difficulties resulting from the supposition
that any and every body, whatever its size, is divisible through and through.
There is, besides, this further consideration. If, having divided a piece
of wood or anything else, I put it together, it is again equal to what
it was, and is one. Clearly this is so, whatever the point at which I cut
the wood. The wood, therefore, has been divided potentially through and
through. What, then, is there in the wood besides the division? For even
if we suppose there is some quality, yet how is the wood dissolved into
such constituents and how does it come-to-be out of them? Or how are such
constituents separated so as to exist apart from one another? Since, therefore,
it is impossible for magnitudes to consist of contacts or points, there
must be indivisible bodies and magnitudes. Yet, if we do postulate the
latter, we are confronted with equally impossible consequences, which we
have examined in other works.' But we must try to disentangle these perplexities,
and must therefore formulate the whole problem over
On the one hand, then, it is in no way paradoxical that every perceptible
body should be indivisible as well as divisible at any and every point.
For the second predicate will at. tach to it potentially, but the first
actually. On the other hand, it would seem to be impossible for a body
to be, even potentially, divisible at all points simultaneously. For if
it were possible, then it might actually occur, with the result, not that
the body would simultaneously be actually both (indivisible and divided),
but that it would be simultaneously divided at any and every point. Consequently,
nothing will remain and the body will have passed-away into what is incorporeal:
and so it might come-to-be again either out of points or absolutely out
of nothing. And how is that possible?
But now it is obvious that a body is in fact divided into separable
magnitudes which are smaller at each division-into magnitudes which fall
apart from one another and are actually separated. Hence (it is urged)
the process of dividing a body part by part is not a 'breaking up' which
could continue ad infinitum; nor can a body be simultaneously divided at
every point, for that is not possible; but there is a limit, beyond which
the 'breaking up' cannot proceed. The necessary consequence-especially
if coming-to-be and passing-away are to take place by 'association' and
'dissociation' respectively-is that a body must contain atomic magnitudes
which are invisible. Such is the argument which is believed to establish
the necessity of atomic magnitudes: we must now show that it conceals a
faulty inference, and exactly where it conceals it.
For, since point is not 'immediately-next' to point, magnitudes
are 'divisible through and through' in one sense, and yet not in another.
When, however, it is admitted that a magnitude is 'divisible through and
through', it is thought there is a point not only anywhere, but also everywhere,
in it: hence it is supposed to follow, from the admission, that the magnitude
must be divided away into nothing. For it is supposed-there is a point
everywhere within it, so that it consists either of contacts or of points.
But it is only in one sense that the magnitude is 'divisible through and
through', viz. in so far as there is one point anywhere within it and all
its points are everywhere within it if you take them singly one by one.
But there are not more points than one anywhere within it, for the points
are not 'consecutive': hence it is not simultaneously 'divisible through
and through'. For if it were, then, if it be divisible at its centre, it
will be divisible also at a point 'immediately-next' to its centre. But
it is not so divisible: for position is not 'immediately-next' to position,
nor point to point-in other words, division is not 'immediately-next' to
division, nor composition to composition.
Hence there are both 'association' and 'dissociation', though neither
(a) into, and out of, atomic magnitudes (for that involves many impossibilities),
nor (b) so that division takes place through and through-for this would
have resulted only if point had been 'immediately-next' to point: but 'dissociation'
takes place into small (i.e. relatively small) parts, and 'association'
takes place out of relatively small parts.
It is wrong, however, to suppose, as some assert, that coming-to-be
and passing-away in the unqualified and complete sense are distinctively
defined by 'association' and 'dissociation', while the change that takes
place in what is continuous is 'alteration'. On the contrary, this is where
the whole error lies. For unqualified coming-to-be and passing-away are
not effected by 'association' and 'dissociation'. They take place when
a thing changes, from this to that, as a whole. But the philosophers we
are criticizing suppose that all such change is 'alteration': whereas in
fact there is a difference. For in that which underlies the change there
is a factor corresponding to the definition and there is a material factor.
When, then, the change is in these constitutive factors, there will be
coming-to-be or passing-away: but when it is in the thing's qualities,
i.e. a change of the thing per accidents, there will be
'Dissociation' and 'association' affect the thing's susceptibility
to passing-away. For if water has first been 'dissociated' into smallish
drops, air comes-to-be out of it more quickly: while, if drops of water
have first been 'associated', air comes-to-be more slowly. Our doctrine
will become clearer in the sequel.' Meantime, so much may be taken as established-viz.
that coming-to-be cannot be 'association', at least not the kind of 'association'
some philosophers assert it to be.
Now that we have established the preceding distinctions, we must
first consider whether there is anything which comes-to-be and passes-away
in the unqualified sense: or whether nothing comes-to-be in this strict
sense, but everything always comes-to-be something and out of something-I
mean, e.g. comes-to-be-healthy out of being-ill and ill out of being-healthy,
comes-to-be-small out of being big and big out of being-small, and so on
in every other instance. For if there is to be coming-to-be without qualification,
'something' must-without qualification-'come-to-be out of not-being', so
that it would be true to say that 'not-being is an attribute of some things'.
For qualified coming-to-be is a process out of qualified not-being (e.g.
out of not-white or not-beautiful), but unqualified coming-to-be is a process
out of unqualified not-being.
Now 'unqulified' means either (i) the primary predication within
each Category, or (ii) the universal, i.e. the all-comprehensive, predication.
Hence, if'unqualified not-being 'means the negation of 'being' in the sense
of the primary term of the Category in question, we shall have, in 'unqualified
coming-to-be', a coming-to-be of a substance out of not-substance. But
that which is not a substance or a 'this' clearly cannot possess predicates
drawn from any of the other Categories either-e.g. we cannot attribute
to it any quality, quantity, or position. Otherwise, properties would admit
of existence in separation from substances. If, on the other hand, 'unqualified
not-being' means 'what is not in any sense at all', it will be a universal
negation of all forms of being, so that what comes-to-be will have to come-to-be
out of nothing.
Although we have dealt with these problems at greater length in
another work,where we have set forth the difficulties and established the
distinguishing definitions, the following concise restatement of our results
must here be offered: In one sense things come-to-be out of that which
has no 'being' without qualification: yet in another sense they come-to-be
always out of what is'. For coming-to-be necessarily implies the pre-existence
of something which potentially 'is', but actually 'is not'; and this something
is spoken of both as 'being' and as 'not-being'.
These distinctions may be taken as established: but even then it
is extraordinarily difficult to see how there can be 'unqualified coming-to-be'
(whether we suppose it to occur out of what potentially 'is', or in some
other way), and we must recall this problem for further examination. For
the question might be raised whether substance (i.e. the 'this') comes-to-be
at all. Is it not rather the 'such', the 'so great', or the 'somewhere',
which comes-to-be? And the same question might be raised about 'passing-away'
also. For if a substantial thing comes-to-be, it is clear that there will
'be' (not actually, but potentially) a substance, out of which its coming-to-be
will proceed and into which the thing that is passing-away will necessarily
change. Then will any predicate belonging to the remaining Categories attach
actually to this presupposed substance? In other words, will that which
is only potentially a 'this' (which only potentially is), while without
the qualification 'potentially' it is not a 'this' (i.e. is not), possess,
e.g. any determinate size or quality or position? For (i) if it possesses
none of these determinations actually, but all of them only potentially,
the result is first that a being, which is not a determinate being, is
capable of separate existence; and in addition that coming-to-be proceeds
out of nothing pre-existing-a thesis which, more than any other, preoccupied
and alarmed the earliest philosophers. On the other hand (ii) if, although
it is not a 'this somewhat' or a substance, it is to possess some of the
remaining determinations quoted above, then (as we said)' properties will
be separable from substances.
We must therefore concentrate all our powers on the discussion
of these difficulties and on the solution of a further question-viz. What
is the cause of the perpetuity of coming-to-be? Why is there always unqualified,
as well as partial, coming-to-be? Cause' in this connexion has two senses.
It means (i) the source from which, as we say, the process 'originates',
and (ii) the matter. It is the material cause that we have here to state.
For, as to the other cause, we have already explained (in our treatise
on Motion that it involves (a) something immovable through all time and
(b) something always being moved. And the accurate treatment of the first
of these-of the immovable 'originative source'-belongs to the province
of the other, or 'prior', philosophy: while as regards 'that which sets
everything else in motion by being itself continuously moved', we shall
have to explain later' which amongst the so-called 'specific' causes exhibits
this character. But at present we are to state the material cause-the cause
classed under the head of matter-to which it is due that passing-away and
coming-to-be never fail to occur in Nature. For perhaps, if we succeed
in clearing up this question, it will simultaneously become clear what
account we ought to give of that which perplexed us just now, i.e. of unqualified
passingaway and coming-to-be.
Our new question too-viz. 'what is the cause of the unbroken continuity
of coming-to-be?'-is sufficiently perplexing, if in fact what passes-away
vanishes into 'what is not' and 'what is not' is nothing (since 'what is
not' is neither a thing, nor possessed of a quality or quantity, nor in
any place). If, then, some one of the things 'which are' constantly disappearing,
why has not the whole of 'what is' been used up long ago and vanished away
assuming of course that the material of all the several comings-to-be was
finite? For, presumably, the unfailing continuity of coming-to-be cannot
be attributed to the infinity of the material. That is impossible, for
nothing is actually infinite. A thing is infinite only potentially, i.e.
the dividing of it can continue indefinitely: so that we should have to
suppose there is only one kind of coming-to-be in the world-viz. one which
never fails, because it is such that what comes-to-be is on each successive
occasion smaller than before. But in fact this is not what we see
Why, then, is this form of change necessarily ceaseless? Is it
because the passing-away of this is a coming-to-be of something else, and
the coming-to-be of this a passing-away of something
The cause implied in this solution must no doubt be considered
adequate to account for coming-to-be and passing-away in their general
character as they occur in all existing things alike. Yet, if the same
process is a coming to-be of this but a passing-away of that, and a passing-away
of this but a coming-to-be of that, why are some things said to come-to-be
and pass-away without qualification, but others only with a
The distinction must be investigated once more, for it demands
some explanation. (It is applied in a twofold manner.) For (i) we say 'it
is now passing-away' without qualification, and not merely 'this is passing-away':
and we call this change 'coming-to-be', and that 'passing-away', without
qualification. And (ii) so-and-so 'comes-to-be-something', but does not
'come-to-be' without qualification; for we say that the student 'comes-to-be-learned',
not 'comes-to-be' without qualification.
(i) Now we often divide terms into those which signify a 'this
somewhat' and those which do not. And (the first form of) the distinction,
which we are investigating, results from a similar division of terms: for
it makes a difference into what the changing thing changes. Perhaps, e.g.
the passage into Fire is 'coming-to-be' unqualified, but 'passingaway-of-something'
(e.g. Earth): whilst the coming-to-be of Earth is qualified (not unqualified)
'coming-to-be', though unqualified 'passing-away' (e.g. of Fire). This
would be the case on the theory set forth in Parmenides: for he says that
the things into which change takes place are two, and he asserts that these
two, viz. what is and what is not, are Fire and Earth. Whether we postulate
these, or other things of a similar kind, makes no difference. For we are
trying to discover not what undergoes these changes, but what is their
characteristic manner. The passage, then, into what 'is' not except with
a qualification is unqualified passing-away, while the passage into what
'is' without qualification is unqualified coming-to-be. Hence whatever
the contrasted 'poles' of the changes may be whether Fire and Earth, or
some other couple-the one of them will be 'a being' and the other 'a
We have thus stated one characteristic manner in which unqualified
will be distinguished from qualified coming-to-be and passing-away: but
they are also distinguished according to the special nature of the material
of the changing thing. For a material, whose constitutive differences signify
more a 'this somewhat', is itself more 'substantial' or 'real': while a
material, whose constitutive differences signify privation, is 'not real'.
(Suppose, e.g. that 'the hot' is a positive predication, i.e. a 'form',
whereas 'cold' is a privation, and that Earth and Fire differ from one
another by these constitutive differences.)
The opinion, however, which most people are inclined to prefer,
is that the distinction depends upon the difference between 'the perceptible'
and 'the imperceptible'. Thus, when there is a change into perceptible
material, people say there is 'coming-to-be'; but when there is a change
into invisible material, they call it 'passing-away'. For they distinguish
'what is' and 'what is not' by their perceiving and not-perceiving, just
as what is knowable 'is' and what is unknowable 'is not'-perception on
their view having the force of knowledge. Hence, just as they deem themselves
to live and to 'be' in virtue of their perceiving or their capacity to
perceive, so too they deem the things to 'be' qua perceived or perceptible-and
in this they are in a sense on the track of the truth, though what they
actually say is not true.
Thus unqualified coming-to-be and passingaway turn out to be different
according to common opinion from what they are in truth. For Wind and Air
are in truth more real more a 'this somewhat' or a 'form'-than Earth. But
they are less real to perception which explains why things are commonly
said to 'pass-away' without qualification when they change into Wind and
Air, and to 'come-to-be' when they change into what is tangible, i.e. into
We have now explained why there is 'unqualified coming-to-be' (though
it is a passingaway-of-something) and 'unqualified passingaway (though
it is a coming-to-be-of-something). For this distinction of appellation
depends upon a difference in the material out of which, and into which,
the changes are effected. It depends either upon whether the material is
or is not 'substantial', or upon whether it is more or less 'substantial',
or upon whether it is more or less perceptible.
(ii) But why are some things said to 'come to-be' without qualification,
and others only to 'come-to-be-so-and-so', in cases different from the
one we have been considering where two things come-to-be reciprocally out
of one another? For at present we have explained no more than this:-why,
when two things change reciprocally into one another, we do not attribute
coming-to-be and passing-away uniformly to them both, although every coming-to-be
is a passing-away of something else and every passing-away some other thing's
coming-to-be. But the question subsequently formulated involves a different
problem-viz. why, although the learning thing is said to 'come-to-be-learned'
but not to 'come-tobe' without qualification, yet the growing thing is
said to 'come-to-be'.
The distinction here turns upon the difference of the Categories.
For some things signify a this somewhat, others a such, and others a so-much.
Those things, then, which do not signify substance, are not said to 'come-to-be'
without qualification, but only to 'come-to-be-so-and-so'. Nevertheless,
in all changing things alike, we speak of 'coming-to-be' when the thing
comes-to-be something in one of the two Columns-e.g. in Substance, if it
comes-to-be Fire but not if it comes-to-be Earth; and in Quality, if it
comes-to-be learned but not when it comes-to-be ignorant.
We have explained why some things come to-be without qualification,
but not others both in general, and also when the changing things are substances
and nothing else; and we have stated that the substratum is the material
cause of the continuous occurrence of coming to-be, because it is such
as to change from contrary to contrary and because, in substances, the
coming-to-be of one thing is always a passing-away of another, and the
passing-away of one thing is always another's coming-to-be. But there is
no need even to discuss the other question we raised-viz. why coming-to-be
continues though things are constantly being destroyed. For just as people
speak of 'a passing-away' without qualification when a thing has passed
into what is imperceptible and what in that sense 'is not', so also they
speak of 'a coming-to-be out of a not-being' when a thing emerges from
an imperceptible. Whether, therefore, the substratum is or is not something,
what comes-tobe emerges out of a 'not-being': so that a thing comes-to-be
out of a not-being' just as much as it 'passes-away into what is not'.
Hence it is reasonable enough that coming-to-be should never fail. For
coming-to-be is a passing-away of 'what is not' and passing-away is a coming
to-be of 'what is not'.
But what about that which 'is' not except with a qualification?
Is it one of the two contrary poles of the chang-e.g. Earth (i.e. the heavy)
a 'not-being', but Fire (i.e. the light) a 'being'? Or, on the contrary,
does what is 'include Earth as well as Fire, whereas what is not' is matter-the
matter of Earth and Fire alike? And again, is the matter of each different?
Or is it the same, since otherwise they would not come-to-be reciprocally
out of one another, i.e. contraries out of contraries? For these things-Fire,
Earth, Water, Air-are characterized by 'the contraries'.
Perhaps the solution is that their matter is in one sense the same,
but in another sense different. For that which underlies them, whatever
its nature may be qua underlying them, is the same: but its actual being
is not the same. So much, then, on these topics.
Next we must state what the difference is between coming-to-be
and 'alteration'-for we maintain that these changes are distinct from one
Since, then, we must distinguish (a) the substratum, and (b) the
property whose nature it is to be predicated of the substratum; and since
change of each of these occurs; there is 'alteration' when the substratum
is perceptible and persists, but changes in its own properties, the properties
in question being opposed to one another either as contraries or as intermediates.
The body, e.g. although persisting as the same body, is now healthy and
now ill; and the bronze is now spherical and at another time angular, and
yet remains the same bronze. But when nothing perceptible persists in its
identity as a substratum, and the thing changes as a whole (when e.g. the
seed as a whole is converted into blood, or water into air, or air as a
whole into water), such an occurrence is no longer 'alteration'. It is
a coming-to-be of one substance and a passing-away of the other-especially
if the change proceeds from an imperceptible something to something perceptible
(either to touch or to all the senses), as when water comes-to-be out of,
or passes-away into, air: for air is pretty well imperceptible. If, however,
in such cases, any property (being one of a pair of contraries) persists,
in the thing that has come-to-be, the same as it was in the thing which
has passedaway-if, e.g. when water comes-to-be out of air, both are transparent
or cold-the second thing, into which the first changes, must not be a property
of this persistent identical something. Otherwise the change will be 'alteration.'
Suppose, e.g. that the musical man passed-away and an unmusical man came-tobe,
and that the man persists as something identical. Now, if 'musicalness
and unmusicalness' had not been a property essentially inhering in man,
these changes would have been a coming-to-be of unmusicalness and a passing-away
of musicalness: but in fact 'musicalness and unmusicalness' are a property
of the persistent identity, viz. man. (Hence, as regards man, these changes
are 'modifications'; though, as regards musical man and unmusical man,
they are a passing-away and a coming-to-be.) Consequently such changes
are 'alteration.' When the change from contrary to contrary is in quantity,
it is 'growth and diminution'; when it is in place, it is 'motion'; when
it is in property, i.e. in quality, it is 'alteration': but, when nothing
persists, of which the resultant is a property (or an 'accident' in any
sense of the term), it is 'coming-to-be', and the converse change is
'Matter', in the most proper sense of the term, is to be identified
with the substratum which is receptive of coming-to-be and passingaway:
but the substratum of the remaining kinds of change is also, in a certain
sense, 'matter', because all these substrata are receptive of 'contrarieties'
of some kind. So much, then, as an answer to the questions (i) whether
coming-to-be 'is' or 'is not'-i.e. what are the precise conditions of its
occurrence and (ii) what 'alteration' is: but we have still to treat of
We must explain (i) wherein growth differs from coming-to-be and
from 'alteration', and ii) what is the process of growing and the sprocess
of diminishing in each and all of the things that grow and
Hence our first question is this: Do these changes differ from
one another solely because of a difference in their respective 'spheres'?
In other words, do they differ because, while a change from this to that
(viz. from potential to actual substance) is coming-to-be, a change in
the sphere of magnitude is growth and one in the sphere of quality is 'alteration'-both
growth and 'alteration' being changes from what is-potentially to what
is-actually magnitude and quality respectively? Or is there also a difference
in the manner of the change, since it is evident that, whereas neither
what is 'altering' nor what is coming-to-be necessarily changes its place,
what is growing or diminishing changes its spatial position of necessity,
though in a different manner from that in which the moving thing does so?
For that which is being moved changes its place as a whole: but the growing
thing changes its place like a metal that is being beaten, retaining its
position as a whole while its parts change their places. They change their
places, but not in the same way as the parts of a revolving globe. For
the parts of the globe change their places while the whole continues to
occupy an equal place: but the parts of the rowing thing expand over an
ever-increasing place and the parts of the diminishing thing contract within
an ever-diminishing area.
It is clear, then, that these changes-the changes of that which
is coming-to-be, of that which is 'altering', and of that which is growing-differ
in manner as well as in sphere. But how are we to conceive the 'sphere'
of the change which is growth and diminution? The sphere' of growing and
diminishing is believed to be magnitude. Are we to suppose that body and
magnitude come-to-be out of something which, though potentially magnitude
and body, is actually incorporeal and devoid of magnitude? And since this
description may be understood in two different ways, in which of these
two ways are we to apply it to the process of growth? Is the matter, out
of which growth takes place, (i) 'separate' and existing alone by itself,
or (ii) 'separate' but contained in another body?
Perhaps it is impossible for growth to take place in either of
these ways. For since the matter is 'separate', either (a) it will occupy
no place (as if it were a point), or (b) it will be a 'void', i.e. a non-perceptible
body. But the first of these alternatives is impossible. For since what
comes-to-be out of this incorporeal and sizeless something will always
be 'somewhere', it too must be 'somewhere'-either intrinsically or indirectly.
And the second alternative necessarily implies that the matter is contained
in some other body. But if it is to be 'in' another body and yet remains
'separate' in such a way that it is in no sense a part of that body (neither
a part of its substantial being nor an 'accident' of it), many impossibilities
will result. It is as if we were to suppose that when, e.g. air comes-to-be
out of water the process were due not to a change of the but to the matter
of the air being 'contained in' the water as in a vessel. This is impossible.
For (i) there is nothing to prevent an indeterminate number of matters
being thus 'contained in' the water, so that they might come-to-be actually
an indeterminate quantity of air; and (ii) we do not in fact see air coming-to-be
out of water in this fashion, viz. withdrawing out of it and leaving it
It is therefore better to suppose that in all instances of coming-to-be
the matter is inseparable, being numerically identical and one with the
'containing' body, though isolable from it by definition. But the same
reasons also forbid us to regard the matter, out of which the body comes-to-be,
as points or lines. The matter is that of which points and lines are limits,
and it is something that can never exist without quality and without
Now it is no doubt true, as we have also established elsewhere,'
that one thing 'comes-tobe' (in the unqualified sense) out of another thing:
and further it is true that the efficient cause of its coming-to-be is
either (i) an actual thing (which is the same as the effect either generically-or
the efficient cause of the coming-to-be of a hard thing is not a hard thing
or specifically, as e.g. fire is the efficient cause of the coming-to-be
of fire or one man of the birth of another), or (ii) an actuality. Nevertheless,
since there is also a matter out of which corporeal substance itself comes-to-be
(corporeal substance, however, already characterized as such-and-such a
determinate body, for there is no such thing as body in general), this
same matter is also the matter of magnitude and quality-being separable
from these matters by definition, but not separable in place unless Qualities
are, in their turn, separable.
It is evident, from the preceding development and discussion of
difficulties, that growth is not a change out of something which, though
potentially a magnitude, actually possesses no magnitude. For, if it were,
the 'void' would exist in separation; but we have explained in a former
work' that this is impossible. Moreover, a change of that kind is not peculiarly
distinctive of growth, but characterizes coming-to-be as such or in general.
For growth is an increase, and diminution is a lessening, of the magnitude
which is there already-that, indeed, is why the growing thing must possess
some magnitude. Hence growth must not be regarded as a process from a matter
without magnitude to an actuality of magnitude: for this would be a body's
coming-to-be rather than its growth.
We must therefore come to closer quarters with the subject of our
inquiry. We must grapple' with it (as it were) from its beginning, and
determine the precise character of the growing and diminishing whose causes
we are investigating.
It is evident (i) that any and every part of the growing thing
has increased, and that similarly in diminution every part has become smaller:
also (ii) that a thing grows by the accession, and diminishes by the departure,
of something. Hence it must grow by the accession either (a) of something
incorporeal or (b) of a body. Now, if (a) it grows by the accession of
something incorporeal, there will exist separate a void: but (as we have
stated before)' is impossible for a matter of magnitude to exist 'separate'.
If, on the other hand (b) it grows by the accession of a body, there will
be two bodies-that which grows and that which increases it-in the same
place: and this too is impossible.
But neither is it open to us to say that growth or diminution occurs
in the way in which e.g. air is generated from water. For, although the
volume has then become greater, the change will not be growth, but a coming
to-be of the one-viz. of that into which the change is taking place-and
a passing-away of the contrasted body. It is not a growth of either. Nothing
grows in the process; unless indeed there be something common to both things
(to that which is coming-to-be and to that which passed-away), e.g. 'body',
and this grows. The water has not grown, nor has the air: but the former
has passed-away and the latter has come-to-be, and-if anything has grown-there
has been a growth of 'body.' Yet this too is impossible. For our account
of growth must preserve the characteristics of that which is growing and
diminishing. And these characteristics are three: (i) any and every part
of the growing magnitude is made bigger (e.g. if flesh grows, every particle
of the flesh gets bigger), (ii) by the accession of something, and (iii)
in such a way that the growing thing is preserved and persists. For whereas
a thing does not persist in the processes of unqualified coming-to-be or
passing-away, that which grows or 'alters' persists in its identity through
the 'altering' and through the growing or diminishing, though the quality
(in 'alteration') and the size (in growth) do not remain the same. Now
if the generation of air from water is to be regarded as growth, a thing
might grow without the accession (and without the persistence) of anything,
and diminish without the departure of anything-and that which grows need
not persist. But this characteristic must be preserved: for the growth
we are discussing has been assumed to be thus characterized.
One might raise a further difficulty. What is 'that which grows'?
Is it that to which something is added? If, e.g. a man grows in his shin,
is it the shin which is greater-but not that 'whereby' he grows, viz. not
the food? Then why have not both 'grown'? For when A is added to B, both
A and B are greater, as when you mix wine with water; for each ingredient
is alike increased in volume. Perhaps the explanation is that the substance
of the one remains unchanged, but the substance of the other (viz. of the
food) does not. For indeed, even in the mixture of wine and water, it is
the prevailing ingredient which is said to have increased in volume. We
say, e.g. that the wine has increased, because the whole mixture acts as
wine but not as water. A similar principle applies also to 'alteration'.
Flesh is said to have been 'altered' if, while its character and substance
remain, some one of its essential properties, which was not there before,
now qualifies it: on the other hand, that 'whereby' it has been 'altered'
may have undergone no change, though sometimes it too has been affected.
The altering agent, however, and the originative source of the process
are in the growing thing and in that which is being 'altered': for the
efficient cause is in these. No doubt the food, which has come in, may
sometimes expand as well as the body that has consumed it (that is so,
e.g. if, after having come in, a food is converted into wind), but when
it has undergone this change it has passedaway: and the efficient cause
is not in the food.
We have now developed the difficulties sufficiently and must therefore
try to find a solution of the problem. Our solution must preserve intact
the three characteristics of growth-that the growing thing persists, that
it grows by the accession (and diminishes by the departure) of something,
and further that every perceptible particle of it has become either larger
or smaller. We must recognize also (a) that the growing body is not 'void'
and that yet there are not two magnitudes in the same place, and (b) that
it does not grow by the accession of something incorporeal.
Two preliminary distinctions will prepare us to grasp the cause
of growth. We must note (i) that the organic parts grow by the growth of
the tissues (for every organ is composed of these as its constituents);
and (ii) that flesh, bone, and every such part-like every other thing which
has its form immersed in matter-has a twofold nature: for the form as well
as the matter is called 'flesh' or 'bone'.
Now, that any and every part of the tissue qua form should grow-and
grow by the accession of something-is possible, but not that any and every
part of the tissue qua matter should do so. For we must think of the tissue
after the image of flowing water that is measured by one and the same measure:
particle after particle comes-to-be, and each successive particle is different.
And it is in this sense that the matter of the flesh grows, some flowing
out and some flowing in fresh; not in the sense that fresh matter accedes
to every particle of it. There is, however, an accession to every part
of its figure or 'form'.
That growth has taken place proportionally, is more manifest in
the organic parts-e.g. in the hand. For there the fact that the matter
is distinct from the form is more manifest than in flesh, i.e. than in
the tissues. That is why there is a greater tendency to suppose that a
corpse still possesses flesh and bone than that it still has a hand or
Hence in one sense it is true that any and every part of the flesh
has grown; but in another sense it is false. For there has been an accession
to every part of the flesh in respect to its form, but not in respect to
its matter. The whole, however, has become larger. And this increase is
due (a) on the one hand to the accession of something, which is called
'food' and is said to be 'contrary' to flesh, but (b) on the other hand
to the transformation of this food into the same form as that of flesh
as if, e.g. 'moist' were to accede to 'dry' and, having acceded, were to
be transformed and to become 'dry'. For in one sense 'Like grows by Like',
but in another sense 'Unlike grows by Unlike'.
One might discuss what must be the character of that 'whereby'
a thing grows. Clearly it must be potentially that which is growing-potentially
flesh, e.g. if it is flesh that is growing. Actually, therefore, it must
be 'other' than the growing thing. This 'actual other', then, has passed-away
and come-to-be flesh. But it has not been transformed into flesh alone
by itself (for that would have been a coming-to-be, not a growth): on the
contrary, it is the growing thing which has come-to-be flesh (and grown)
by the food. In what way, then, has the food been modified by the growing
thing? Perhaps we should say that it has been 'mixed' with it, as if one
were to pour water into wine and the wine were able to convert the new
ingredient into wine. And as fire lays hold of the inflammable, so the
active principle of growth, dwelling in the growing thing that which is
actually flesh), lays hold of an acceding food which is potentially flesh
and converts it into actual flesh. The acceding food, therefore, must be
together with the growing thing: for if it were apart from it, the change
would be a coming-to-be. For it is possible to produce fire by piling logs
on to the already burning fire. That is 'growth'. But when the logs themselves
are set on fire, that is 'coming-to-be'.
'Quantum-in-general' does not come-to-be any more than 'animal'
which is neither man nor any other of the specific forms of animal: what
'animal-in-general' is in coming-to-be, that 'quantum-in-general' is in
growth. But what does come-to-be in growth is flesh or bone-or a hand or
arm (i.e. the tissues of these organic parts). Such things come-to-be,
then, by the accession not of quantified-flesh but of a quantified-something.
In so far as this acceding food is potentially the double result e.g. is
potentially so-much-flesh-it produces growth: for it is bound to become
actually both so-much and flesh. But in so far as it is potentially flesh
only, it nourishes: for it is thus that 'nutrition' and 'growth' differ
by their definition. That is why a body's' nutrition' continues so long
as it is kept alive (even when it is diminishing), though not its 'growth';
and why nutrition, though 'the same' as growth, is yet different from it
in its actual being. For in so far as that which accedes is potentially
'so much-flesh' it tends to increase flesh: whereas, in so far as it is
potentially 'flesh' only, it is nourishment.
The form of which we have spoken is a kind of power immersed in
matter-a duct, as it were. If, then, a matter accedes-a matter, which is
potentially a duct and also potentially possesses determinate quantity
the ducts to which it accedes will become bigger. But if it is no longer
able to act-if it has been weakened by the continued influx of matter,
just as water, continually mixed in greater and greater quantity with wine,
in the end makes the wine watery and converts it into water-then it will
cause a diminution of the quantum; though still the form
(In discussing the causes of coming-tobe) we must first investigate
the matter, i.e. the so-called 'elements'. We must ask whether they really
are clements or not, i.e. whether each of them is eternal or whether there
is a sense in which they come-to-be: and, if they do come-to-be, whether
all of them come-to-be in the same manner reciprocally out of one another,
or whether one amongst them is something primary. Hence we must begin by
explaining certain preliminary matters, about which the statements now
current are vague.
For all (the pluralist philosophers)- those who generate the 'elements'
as well as those who generate the bodies that are compounded of the elements-
make use of 'dissociation' and 'association', and of 'action' and 'passion'.
Now 'association' is 'combination'; but the precise meaning of the process
we call 'combining' has not been explained. Again, (all the monists make
use of 'alteration': but) without an agent and a patient there cannot be
'altering' any more than there can be 'dissociating' and 'associating'.
For not only those who postulate a plurality of elements employ their reciprocal
action and passion to generate the compounds: those who derive things from
a single element are equally compelled to introduce 'acting'. And in this
respect Diogenes is right when he argues that 'unless all things were derived
from one, reciprocal action and passion could not have occurred'. The hot
thing, e.g. would not be cooled and the cold thing in turn be warmed: for
heat and cold do not change reciprocally into one another, but what changes
(it is clear) is the substratum. Hence, whenever there is action and passion
between two things, that which underlies them must be a single something.
No doubt, it is not true to say that all things are of this character:
but it is true of all things between which there is reciprocal action and
But if we must investigate 'action-passion' and 'combination',
we must also investigate 'contact'. For action and passion (in the proper
sense of the terms) can only occur between things which are such as to
touch one another; nor can things enter into combination at all unless
they have come into a certain kind of contact. Hence we must give a definite
account of these three things- of 'contact', 'combination', and
Let us start as follows. All things which admit of 'combination'
must be capable of reciprocal contact: and the same is true of any two
things, of which one 'acts' and the other 'suffers action' in the proper
sense of the terms. For this reason we must treat of 'contact' first. every
term which possesses a variety of meaning includes those various meanings
either owing to a mere coincidence of language, or owing to a real order
of derivation in the different things to which it is applied: but, though
this may be taken to hold of 'contact' as of all such terms, it is nevertheless
true that contact' in the proper sense applies only to things which have
'position'. And 'position' belongs only to those things which also have
a Place': for in so far as we attribute 'contact' to the mathematical things,
we must also attribute 'place' to them, whether they exist in separation
or in some other fashion. Assuming, therefore, that 'to touch' is-as we
have defined it in a previous work'-'to have the extremes together', only
those things will touch one another which, being separate magnitudes and
possessing position, have their extremes 'together'. And since position
belongs only to those things which also have a 'place', while the primary
differentiation of 'place' is the above' and 'the below' (and the similar
pairs of opposites), all things which touch one another will have 'weight'
or 'lightness' either both these qualities or one or the other of them.
But bodies which are heavy or light are such as to 'act' and 'suffer action'.
Hence it is clear that those things are by nature such as to touch one
another, which (being separate magnitudes) have their extremes 'together'
and are able to move, and be moved by, one another.
The manner in which the 'mover' moves the moved' not always the
same: on the contrary, whereas one kind of 'mover' can only impart motion
by being itself moved, another kind can do so though remaining itself unmoved.
Clearly therefore we must recognize a corresponding variety in speaking
of the 'acting' thing too: for the 'mover' is said to 'act' (in a sense)
and the 'acting' thing to 'impart motion'. Nevertheless there is a difference
and we must draw a distinction. For not every 'mover' can 'act', if (a)
the term 'agent' is to be used in contrast to 'patient' and (b) 'patient'
is to be applied only to those things whose motion is a 'qualitative affection'-i.e.
a quality, like white' or 'hot', in respect to which they are moved' only
in the sense that they are 'altered': on the contrary, to 'impart motion'
is a wider term than to 'act'. Still, so much, at any rate, is clear: the
things which are 'such as to impart motion', if that description be interpreted
in one sense, will touch the things which are 'such as to be moved by them'-while
they will not touch them, if the description be interpreted in a different
sense. But the disjunctive definition of 'touching' must include and distinguish
(a) 'contact in general' as the relation between two things which, having
position, are such that one is able to impart motion and the other to be
moved, and (b) 'reciprocal contact' as the relation between two things,
one able to impart motion and the other able to be moved in such a way
that 'action and passion' are predicable of them.
As a rule, no doubt, if A touches B, B touches A. For indeed practically
all the 'movers' within our ordinary experience impart motion by being
moved: in their case, what touches inevitably must, and also evidently
does, touch something which reciprocally touches it. Yet, if A moves B,
it is possible-as we sometimes express it-for A 'merely to touch' B, and
that which touches need not touch a something which touches it. Nevertheless
it is commonly supposed that 'touching' must be reciprocal. The reason
of this belief is that 'movers' which belong to the same kind as the 'moved'
impart motion by being moved. Hence if anything imparts motion without
itself being moved, it may touch the 'moved' and yet itself be touched
by nothing-for we say sometimes that the man who grieves us 'touches' us,
but not that we 'touch' him.
The account just given may serve to distinguish and define the
'contact' which occurs in the things of Nature.
Next in order we must discuss 'action' and 'passion'. The traditional
theories on the subject are conflicting. For (i) most thinkers are unanimous
in maintaining (a) that 'like' is always unaffected by 'like', because
(as they argue) neither of two 'likes' is more apt than the other either
to act or to suffer action, since all the properties which belong to the
one belong identically and in the same degree to the other; and (b) that
'unlikes', i.e. 'differents', are by nature such as to act and suffer action
reciprocally. For even when the smaller fire is destroyed by the greater,
it suffers this effect (they say) owing to its 'contrariety' since the
great is contrary to the small. But (ii) Democritus dissented from all
the other thinkers and maintained a theory peculiar to himself. He asserts
that agent and patient are identical, i.e. 'like'. It is not possible (he
says) that 'others', i.e. 'differents', should suffer action from one another:
on the contrary, even if two things, being 'others', do act in some way
on one another, this happens to them not qua 'others' but qua possessing
an identical property.
Such, then, are the traditional theories, and it looks as if the
statements of their advocates were in manifest conflict. But the reason
of this conflict is that each group is in fact stating a part, whereas
they ought to have taken a comprehensive view of the subject as a whole.
For (i) if A and B are 'like'-absolutely and in all respects without difference
from one another -it is reasonable to infer that neither is in any way
affected by the other. Why, indeed, should either of them tend to act any
more than the other? Moreover, if 'like' can be affected by 'like', a thing
can also be affected by itself: and yet if that were so-if 'like' tended
in fact to act qua 'like'-there would be nothing indestructible or immovable,
for everything would move itself. And (ii) the same consequence follows
if A and B are absolutely 'other', i.e. in no respect identical. Whiteness
could not be affected in any way by line nor line by whiseness-except perhaps
'coincidentally', viz. if the line happened to be white or black: for unless
two things either are, or are composed of, 'contraries', neither drives
the other out of its natural condition. But (iii) since only those things
which either involve a 'contrariety' or are 'contraries'-and not any things
selected at random-are such as to suffer action and to act, agent and patient
must be 'like' (i.e. identical) in kind and yet 'unlike' (i.e. contrary)
in species. (For it is a law of nature that body is affected by body, flavour
by flavour, colour by colour, and so in general what belongs to any kind
by a member of the same kind-the reason being that 'contraries' are in
every case within a single identical kind, and it is 'contraries' which
reciprocally act and suffer action.) Hence agent and patient must be in
one sense identical, but in another sense other than (i.e. 'unlike') one
another. And since (a) patient and agent are generically identical (i.e.
'like') but specifically 'unlike', while (b) it is 'contraries' that exhibit
this character: it is clear that 'contraries' and their 'intermediates'
are such as to suffer action and to act reciprocally-for indeed it is these
that constitute the entire sphere of passing-away and
We can now understand why fire heats and the cold thing cools,
and in general why the active thing assimilates to itself the patient.
For agent and patient are contrary to one another, and coming-to-be is
a process into the contrary: hence the patient must change into the agent,
since it is only thus that coming-to be will be a process into the contrary.
And, again, it is intelligible that the advocates of both views, although
their theories are not the same, are yet in contact with the nature of
the facts. For sometimes we speak of the substratum as suffering action
(e.g. of 'the man' as being healed, being warmed and chilled, and similarly
in all the other cases), but at other times we say 'what is cold is 'being
warmed', 'what is sick is being healed': and in both these ways of speaking
we express the truth, since in one sense it is the 'matter', while in another
sense it is the 'contrary', which suffers action. (We make the same distinction
in speaking of the agent: for sometimes we say that 'the man', but at other
times that 'what is hot', produces heat.) Now the one group of thinkers
supposed that agent and patient must possess something identical, because
they fastened their attention on the substratum: while the other group
maintained the opposite because their attention was concentrated on the
'contraries'. We must conceive the same account to hold of action and passion
as that which is true of 'being moved' and 'imparting motion'. For the
'mover', like the 'agent', has two meanings. Both (a) that which contains
the originative source of the motion is thought to 'impart motion' (for
the originative source is first amongst the causes), and also (b) that
which is last, i.e. immediately next to the moved thing and to the coming-to-be.
A similar distinction holds also of the agent: for we speak not only (a)
of the doctor, but also (b) of the wine, as healing. Now, in motion, there
is nothing to prevent the firs; mover being unmoved (indeed, as regards
some 'first' movers' this is actually necessary) although the last mover
always imparts motion by being itself moved: and, in action, there is nothing
to prevent the first agent being unaffected, while the last agent only
acts by suffering action itself. For agent and patient have not the same
matter, agent acts without being affected: thus the art of healing produces
health without itself being acted upon in any way by that which is being
healed. But (b) the food, in acting, is itself in some way acted upon:
for, in acting, it is simultaneously heated or cooled or otherwise affected.
Now the art of healing corresponds to an 'originative source', while the
food corresponds to 'the last' (i.e. 'continuous') mover.
Those active powers, then, whose forms are not embodied in matter,
are unaffected: but those whose forms are in matter are such as to be affected
in acting. For we maintain that one and the same 'matter' is equally, so
to say, the basis of either of the two opposed things-being as it were
a 'kind'; and that that which can he hot must be made hot, provided the
heating agent is there, i.e. comes near. Hence (as we have said) some of
the active powers are unaffected while others are such as to be affected;
and what holds of motion is true also of the active powers. For as in motion
'the first mover' is unmoved, so among the active powers 'the first agent'
The active power is a 'cause' in the sense of that from which the
process originates: but the end, for the sake of which it takes place,
is not 'active'. (That is why health is not 'active', except metaphorically.)
For when the agent is there, the patient he-comes something: but when 'states'
are there, the patient no longer becomes but already is-and 'forms' (i.e.
lends') are a kind of 'state'. As to the 'matter', it (qua matter) is passive.
Now fire contains 'the hot' embodied in matter: but a 'hot' separate from
matter (if such a thing existed) could not suffer any action. Perhaps,
indeed, it is impossible that 'the hot' should exist in separation from
matter: but if there are any entities thus separable, what we are saying
would be true of them.
We have thus explained what action and passion are, what things
exhibit them, why they do so, and in what manner. We must go on to discuss
how it is possible for action and passion to take place.
Some philosophers think that the 'last' agent-the 'agent' in the
strictest sense-enters in through certain pores, and so the patient suffers
action. It is in this way, they assert, that we see and hear and exercise
all our other senses. Moreover, according to them, things are seen through
air and water and other transparent bodies, because such bodies possess
pores, invisible indeed owing to their minuteness, but close-set and arranged
in rows: and the more transparent the body, the more frequent and serial
they suppose its pores to be. Such was the theory which some philosophers
(induding Empedocles) advanced in regard to the structure of certain bodies.
They do not restrict it to the bodies which act and suffer action: but
'combination' too, they say, takes place 'only between bodies whose pores
are in reciprocal symmetry'. The most systematic and consistent theory,
however, and one that applied to all bodies, was advanced by Leucippus
and Democritus: and, in maintaining it, they took as their starting-point
what naturally comes first.
For some of the older philosophers thought that 'what is' must
of necessity be 'one' and immovable. The void, they argue, 'is not': but
unless there is a void with a separate being of its own, 'what is' cannot
be moved-nor again can it be 'many', since there is nothing to keep things
apart. And in this respect, they insist, the view that the universe is
not 'continuous' but 'discretes-in-contact' is no better than the view
that there are 'many' (and not 'one') and a void. For (suppose that the
universe is discretes-in-contact. Then), if it is divisible through and
through, there is no 'one', and therefore no 'many' either, but the Whole
is void; while to maintain that it is divisible at some points, but not
at others, looks like an arbitrary fiction. For up to what limit is it
divisible? And for what reason is part of the Whole indivisible, i.e. a
plenum, and part divided? Further, they maintain, it is equally necessary
to deny the existence of motion.
Reasoning in this way, therefore, they were led to transcend sense-perception,
and to disregard it on the ground that 'one ought to follow the argument':
and so they assert that the universe is 'one' and immovable. Some of them
add that it is 'infinite', since the limit (if it had one) would be a limit
against the void.
There were, then, certain thinkers who, for the reasons we have
stated, enunciated views of this kind as their theory of 'The Truth'....
Moreover, although these opinions appear to follow logically in a dialectical
discussion, yet to believe them seems next door to madness when one considers
the facts. For indeed no lunatic seems to be so far out of his senses as
to suppose that fire and ice are 'one': it is only between what is right
and what seems right from habit, that some people are mad enough to see
Leucippus, however, thought he had a theory which harmonized with
sense-perception and would not abolish either coming-to-be and passing-away
or motion and the multiplicity of things. He made these concessions to
the facts of perception: on the other hand, he conceded to the Monists
that there could be no motion without a void. The result is a theory which
he states as follows: 'The void is a "not being", and no part of "what
is" is a "not-being"; for what "is" in the strict sense of the term is
an absolute plenum. This plenum, however, is not "one": on the contrary,
it is a many" infinite in number and invisible owing to the minuteness
of their bulk. The "many" move in the void (for there is a void): and by
coming together they produce "coming to-be", while by separating they produce
"passing-away". Moreover, they act and suffer action wherever they chance
to be in contact (for there they are not "one"), and they generate by being
put together and becoming intertwined. From the genuinely-one, on the other
hand, there never could have come-to-be a multiplicity, nor from the genuinely-many
a "one": that is impossible. But' (just as Empedocles and some of the other
philosophers say that things suffer action through their pores, so) 'all
"alteration" and all "passion" take place in the way that has been explained:
breaking-up (i.e. passing-away) is effected by means of the void, and so
too is growth-solids creeping in to fill the void places.' Empedocles too
is practically bound to adopt the same theory as Leucippus. For he must
say that there are certain solids which, however, are indivisible-unless
there are continuous pores all through the body. But this last alternative
is impossible: for then there will be nothing solid in the body (nothing
beside the pores) but all of it will be void. It is necessary, therefore,
for his 'contiguous discretes' to be indivisible, while the intervals between
them-which he calls 'pores'-must be void. But this is precisely Leucippus'
theory of action and passion.
Such, approximately, are the current explanations of the manner
in which some things 'act' while others 'suffer action'. And as regards
the Atomists, it is not only clear what their explanation is: it is also
obvious that it follows with tolerable consistency from the assumptions
they employ. But there is less obvious consistency in the explanation offered
by the other thinkers. It is not clear, for instance, how, on the theory
of Empedocles, there is to be 'passing-away' as well as 'alteration'. For
the primary bodies of the Atomists-the primary constituents of which bodies
are composed, and the ultimate elements into which they are dissolved-are
indivisible, differing from one another only in figure. In the philosophy
of Empedocles, on the other hand, it is evident that all the other bodies
down to the 'elements' have their coming-to-be and their passingaway: but
it is not clear how the 'elements' themselves, severally in their aggregated
masses, come-to-be and pass-away. Nor is it possible for Empedocles to
explain how they do so, since he does not assert that Fire too (and similarly
every one of his other 'elements') possesses 'elementary constituents'
Such an assertion would commit him to doctrines like those which
Plato has set forth in the Ti