The Complete Works of Aristotle

  From which grew all that was and is and will be hereafter—

  [30] Trees, and men and women, and beasts and birds

  And water-nourished fish, and long-aged gods.

  The implication is evident even apart from these words; for if strife had not been [1000b1] present in things, all things would have been one, as he says—‘when they have come together, strife stands outermost’. Hence it also follows on his theory that God most blessed is less wise than all others; for he does not know all the elements; for he has [5] in him no strife, and knowledge is of the like by the like. ‘For by earth,’ he says,

  we see earth, by water water,

  By ether godlike ether, by fire wasting fire,

  Love by love, and strife by gloomy strife.

  But—and this is the point we started from—this at least is evident, that on his [10] theory it follows that strife is as much the cause of existence as of destruction. And similarly friendship is not specially the cause of existence; for in collecting things into the One it destroys all other things.—And at the same time Empedocles mentions no cause of the change itself, except that things are so by nature.

  But when strife waxed great in the limbs.

  [15] And sprang to honour as the time was fulfilled

  Which is fixed for them in turn by a mighty oath.

  This implies that change was necessary; but he shows no cause of the necessity. But yet so far at least he alone speaks consistently; for he does not make some things perishable and others imperishable, but makes all perishable except the elements. [20] The difficulty we are speaking of now is, why some things are perishable and others are not, if they consist of the same principles.

  Let this suffice as proof of the fact that the principles cannot be the same. But if there are different principles, one difficulty is whether these themselves will be imperishable or perishable. For if they are perishable, evidently these also must consist of certain elements; for all things that perish, perish by being resolved into [25] the elements of which they consist; so that it follows that prior to the principles there are other principles. And this is impossible, whether the process has a limit or proceeds to infinity. Further, how will perishable things exist, if their principles are to be destroyed? But if the principles are imperishable, why will things composed of some imperishable principles be perishable, while those composed of the others are [30] imperishable? This is not probable, but is either impossible or needs much proof. Further, no one has even tried to maintain different principles; they maintain the same principles for all things. But they swallow the difficulty we stated first as if [1001a1] they took it to be something trifling.

  The hardest inquiry of all, and the one most necessary for knowledge of the truth, is whether being and unity are the substances of things, and whether each of [5] them, without being anything else, is being or unity respectively, or whether we must inquire what being and unity are, with the implication that they have some other underlying nature. For some people think they are of the former, others think they are of the latter character. Plato and the Pythagoreans thought being and [10] unity were nothing else, but this was their nature, their substance being just unity and being. But the natural philosophers take a different line; e.g. Empedocles—as though referring it to something more intelligible—says what unity is; for he would seem to say it is love: at least, this is for all things the cause of their being one. [15] Others say this unity and being, of which things consist and have been made, is fire, and others say it is air. A similar view is expressed by those who make the elements more than one; for these also must say that being and unity are precisely all the things which they say are principles. If we do not suppose unity and being to be [20] substances, it follows that none of the other universals is a substance; for these are most universal of all. If there is no unity-itself or being-itself, there will scarcely be in any other case anything apart from what are called the individuals. Further, if unity is not a substance, evidently number also will not exist as an entity separate [25] from the individual things; for number is units, and the unit is something whose essence it is to be one.—But if there is a unity-itself and a being-itself, their substance must be unity and being; for it is not something else that is predicated universally of them, but just unity and being. But if there is to be a being-itself and a unity-itself, there is much difficulty in seeing how there will be anything else besides [30] these—I mean, how things will be more than one in number. For what is different from being does not exist, so that it necessarily follows, according to the argument of Parmenides, that all things that are are one and this is being.—There are [1001b1] objections to both views. For whether unity is not a substance or there is a unity-itself, number cannot be a substance. We have already said why this result follows if unity is not a substance: and if it is, the same difficulty arises as arose with regard to being. For whence is there to be another one besides the unity-itself? It [5] must be not-one; but all things are either one or many, and of the many each is one.—Further, if the unity-itself is indivisible, according to Zeno’s doctrine it will be nothing. For that which neither when added makes a thing greater nor when subtracted makes it less, he asserts to have no being, evidently assuming that [10] whatever has being is a spatial magnitude. And if it is a magnitude, it is corporeal; for the corporeal has being in every dimension, while the other objects of mathematics, e.g. a plane or a line, added in one way will increase what they are added to, but in another way will not do so, and a point or a unit does so in no way. But since he argues crudely, an indivisible thing can exist, so that the position may [15] be defended even against him; for the indivisible when added will make the number, though not the size, greater. But how can a magnitude proceed from one such indivisible or from many? It is like saying that the line is made out of points. But [20] even if one supposes the case to be such that, as some say, number proceeds from the unity-itself and something else which is not one, none the less we must inquire why and how the product will be sometimes a number and sometimes a magnitude, if the not-one was inequality and was the same principle in either case. For it is not evident how magnitudes could proceed either from the one and this principle, or [25] from some number and this principle.

  5 · A question connected with these is whether numbers and bodies and planes and points are substances or not. If they are not, it baffles us to say what being is and what the substances of things are. For modifications and movements [30] and relations and dispositions and ratios do not seem to indicate the substance of anything; for all are predicated of a subject, and none is a ‘this’. And as to the things which might seem most of all to indicate substance, water and earth and fire and [1002a1] air, of which composite bodies consist, heat and cold and the like are modifications of these, not substances, and the body which is thus modified alone persists as something real and as a substance. But, on the other hand, a body is surely less of a [5] substance than a surface, and a surface less than a line, and a line less than a unit and a point. For a body is bounded by these; and they are thought to be capable of existing without body, but a body cannot exist without these. This is why, while most of the philosophers and the earlier among them thought that substance and being were identical with body, and that all other things were attributes of this, so [10] that the first principles of bodies were the first principles of being, the more recent and those who were held to be wiser thought numbers were the first principles. As we said, then, if these are not substance, there is no substance and no being at all; for surely it is not proper to call the accidents of these, beings. But if this is admitted, [15] that lines and points are substance more than bodies, but we do not see to what sort of bodies these could belong (for they cannot be in perceptible bodies), there can be no substance.—Further, these are all evidently divisions of body,—one a division in [20] breadth, another in depth, another in length.—Besides this, no sort of shape is present in the solid more than any other; so that if the Hermes is not in th
e stone, neither is the half of the cube in the cube as something determinate; therefore the surface is not in it either; for if any sort of surface were in it, the surface which marks off the half of the cube would be in it too. And the same account applies to [25] the line and to the point and the unit. Therefore, if on the one hand body is in the highest degree substance, and on the other hand these things are so more than body, but these are not even instances of substance, it baffles us to say what being is and what the substance of things is.—For besides what has been said, the questions of generation and destruction confront us with further paradoxes. For if substance, not having existed before, now exists, or having existed before, afterwards does not [30] exist, this change is thought to be accompanied by a process of becoming or perishing; but points and lines and surfaces cannot be in process of becoming nor of perishing, though they at one time exist and at another do not. For when bodies come into contact or are separated, their boundaries instantaneously become one at [1002b1] one time—when they touch, and two at another time—when they are separated; so that when they have been put together one boundary does not exist but has perished, and when they have been separated the boundaries exist which before did not exist. For it cannot be said that the point (which is indivisible) was divided into two. And if the boundaries come into being and cease to be, from what do they come into [5] being? A similar account may also be given of the ‘now’ in time; for this also cannot be in process of coming into being or of ceasing to be, but yet seems to be always different, which shows that it is not a substance. And evidently the same is true of points and lines and planes; for the same argument applies, as they are all alike [10] either limits or divisions.

  6 · In general one might raise the question why, besides perceptible things and the intermediates, we have to look for another class of things, such as the Forms which we posit. If it is for this reason, because the objects of mathematics, while they differ from the things in this world in some other respect, differ not at all in [15] that there are many of the same kind, so that their first principles cannot be limited in number (just as the elements of all the language in this sensible world are not limited in number, but in kind, unless one takes the elements of this individual syllable or of this individual articulate sound—whose elements will be limited even [20] in number—, so is it also in the case of the intermediates; for there also the members of the same kind are infinite in number), so that if there are not—besides perceptible and mathematical objects—others such as some maintain the Forms to be, there will be no substance which is one in number as well as in kind, nor will the first principles of things be determinate in number, but only in kind—if then this [25] must be so, the Forms also must therefore be held to exist. Even if those who support this view do not express it distinctly, still this is what they mean, and they must be maintaining the Forms just because each of the Forms is a substance and none is by accident. But if we are to suppose that the Forms exist and the principles are one in [30] number, not in kind, the impossible results that we have mentioned necessarily follow.

  Closely connected with this is the question whether the elements exist potentially or in some other way. If in some other way, there will be something else prior to the first principles; for the potency is prior to the actual cause, and it is not [1003a1] necessary for everything potential to be actual.—But if the elements exist potentially, it is possible that everything that is should not be. For even that which is not yet is capable of being; for that which is not comes to be, but nothing that is incapable of being comes to be. [5]

  We must not only raise these questions about the first principles, but also ask whether they are universal or what we call individuals. If they are universal, they will not be substances; for everything that is common indicates not a ‘this’ but a [10] ‘such’, but substance is a ‘this’.—And if we can actually posit the common predicate as a single ‘this’, Socrates will be several animals—himself and man and animal, if each of these indicates a ‘this’ and a single thing.—If, then, the principles are universals, these results follow; if they are not universals but of the nature of individuals, they will not be knowable; for the knowledge of anything is universal. [15] Therefore if there is to be knowledge of the principles there must be other principles prior to them, which are universally predicated of them.

  BOOK IV(Γ)

  1 · There is a science which investigates being as being and the attributes which belong to this in virtue of its own nature. Now this is not the same as any of the so-called special sciences; for none of these others deals generally with being as [25] being. They cut off a part of being and investigate the attributes of this part—this is what the mathematical sciences for instance do. Now since we are seeking the first principles and the highest causes, clearly there must be some thing to which these belong in virtue of its own nature. If then our predecessors who sought the elements of existing things were seeking these same principles, it is necessary that the [30] elements must be elements of being not by accident but just because it is being. Therefore it is of being as being that we also must grasp the first causes.

  2 · There are many senses in which a thing may be said to ‘be’, but they are related to one central point, one definite kind of thing, and are not homonymous. [35] Everything which is healthy is related to health, one thing in the sense that it preserves health, another in the sense that it produces it, another in the sense that it is a symptom of health, another because it is capable of it. And that which is [1003b1] medical is relative to the medical art, one thing in the sense that it possesses it, another in the sense that it is naturally adapted to it, another in the sense that it is a function of the medical art. And we shall find other words used similarly to these. [5] So, too, there are many senses in which a thing is said to be, but all refer to one starting-point; some things are said to be because they are substances, others because they are affections of substance, others because they are a process towards substance, or destructions or privations or qualities of substance, or productive or generative of substance, or of things which are relative to substance, or negations of [10] some of these things or of substance itself. It is for this reason that we say even of non-being that it is non-being. As, then, there is one science which deals with all healthy things, the same applies in the other cases also. For not only in the case of things which have one common notion does the investigation belong to one science, but also in the case of things which are related to one common nature; for even these in a sense have one common notion. It is clear then that it is the work of one science [15] also to study all things that are, qua being.—But everywhere science deals chiefly with that which is primary, and on which the other things depend, and in virtue of which they get their names. If, then, this is substance, it is of substances that the philosopher must grasp the principles and the causes.

  Now for every single class of things, as there is one perception, so there is one science, as for instance grammar, being one science, investigates all articulate [20] sounds. Therefore to investigate all the species of being qua being, is the work of a science which is generically one, and to investigate the several species is the work of the specific parts of the science.

  If, now, being and unity are the same and are one thing in the sense that they are implied in one another as principle and cause are, not in the sense that they are explained by the same formula (though it makes no difference even if we interpret [25] them similarly—in fact this would strengthen our case); for one man and a man are the same thing and existent man and a man are the same thing, and the doubling of the words in ‘one man’ and ‘one existent man’ does not give any new meaning (it is clear that they are not separated either in coming to be or in ceasing to be); and similarly with ‘one’, so that it is obvious that the addition in these cases means the [30] same thing, and unity is nothing apart from being; and if, further, the essence of each thing is one in no merely accidental way, and similarly is from its very nature
something that is:—all this being so, there must be exactly as many species of being as of unity. And to investigate the essence of these is the work of a science which is generically one—I mean, for instance, the discussion of the same and the similar [35] and the other concepts of this sort; and nearly all contraries are referred to this source; but let us take them as having been investigated in the ‘Selection of [1004a1] Contraries’.—And there are as many parts of philosophy as there are kinds of substance, so that there must necessarily be among them a first philosophy and one which follows this. For being falls immediately into genera; and therefore the [5] sciences too will correspond to these genera. For ‘philosopher’ is like ‘mathematician’; for mathematics also has parts, and there is a first and a second science and other successive ones within the sphere of mathematics.