The Politics of Aristotle

by Aristotle

  [1018b1] Things are said to be other in species if they are of the same genus but are not subordinate the one to the other, or if, while being in the same genus they have a difference, or if they have a contrariety in their substance; and contraries are other than one another in species (either all contraries or those which are so called in the [5] primary sense), and so are those things whose formulae differ in the infima species of the genus (e.g. man and horse are indivisible in genus, but their formulae are different), or which being in the same substance have a difference. ‘The same in species’ is used correspondingly.

  11 · We call things prior and posterior (1) in some cases (on the assumption [10] that there is a first, i.e. a beginning, in each class) because they are nearer some beginning determined either absolutely and by nature, or by reference to something or in some place or by certain people, e.g. things are prior in place because they are nearer either to some place determined by nature, e.g. the middle or the last place, or to some chance object; and that which is further is posterior.—Other things are [15] prior in time; some by being further from the present, i.e. in the case of past events (for the Trojan war is prior to the Persian, because it is further from the present), others by being nearer the present, i.e. in the case of future events (for the Nemean games are prior to the Pythian, if we treat the present as beginning and first point, because they are nearer the present).—Other things are prior in movement; for the [20] things that are nearer the first mover are prior (e.g. the boy is prior to the man); and the prime mover also is a beginning absolutely.—Others are prior in power; for that which exceeds in power, i.e. the more powerful, is prior; and such is that according to whose choice the other—i.e. the posterior—must follow, so that if the prior does [25] not set it in motion the other does not move, and if it sets it in motion it does move; and here choice is a beginning.—Others are prior in arrangement; these are the things that are placed at certain intervals in reference to some one definite thing according to some rule, e.g. the second member of the chorus is prior to the third, and the second-lowest string is prior to the lowest; for in the one case the leader and in the other the middle string is the beginning.

  These, then, are called prior in this sense, but (2) in another sense that which is [30] prior for knowledge is treated as absolutely prior; of these, the things that are prior in formula are different from those that are prior in perception. For in formula universals are prior in perception. For in formula universals are prior, in perception individuals. And in formula also the accident is prior to the whole, e.g. musical to musical man, for the formula cannot exist as a whole without the part; yet [35] musicalness cannot exist unless there is someone who is musical.

  (3) The attributes of prior things are called prior, e.g. straightness is prior to smoothness; for one is an attribute of a line as such, and the other of a surface. [1019a1]

  Some things then are called prior and posterior in this sense, others (4) in respect of nature and substance, i.e. those which can be without other things, while the others cannot be without them—a distinction which Plato used. If we consider the various senses of ‘being’, firstly the subject is prior (so that substance is prior); [5] secondly, according as capacity or actuality is taken into account, different things are prior, for some things are prior in respect of capacity, others in respect of actuality, e.g. in capacity the half line is prior to the whole line and the part to the whole and the matter to the substance, but in actuality these are posterior; for it is only when the whole is dissolved that they will exist in actuality. In a sense, [10] therefore, all things that are called prior and posterior are so called according to this fourth sense; for some things can exist without others in respect of generation, e.g. the whole without the parts, and others in respect of dissolution, e.g. the part without the whole. And the same is true in all other cases.

  12 · We call a capacity (1) a source of movement or change, which is in [15] another thing or in the same thing qua other, e.g. the art of building is a capacity which is not in the thing built, while the art of healing, which is a capacity, might be in the man healed, but not in him qua healed. Capacity then is the source, in general, of change or movement in another thing or in the same thing qua other, and also the source of a thing’s being moved by another thing or by itself qua other. For [20] in virtue of that principle, in virtue of which the patient suffers anything, we call it capable of suffering; and this we do sometimes if it suffers anything at all, sometimes not in respect of everything it suffers, but only if it suffers a change for the better.—(2) The capacity of performing this well or according to choice; for sometimes we say of those who merely can walk or speak but not well or not as they choose, that they cannot speak or walk. The case of passivity is similar.—(3) The [25] states in virtue of which things are absolutely impassive or unchangeable, or not easily changed for the worse, are called capacities; for things are broken and crushed and bent and in general destroyed not by having a capacity but by not having one and by lacking something, and things are impassive with respect to such [30] processes if they are scarcely and slightly affected by them, because of a capacity and because they can do something and are in some positive state.

  As capacity is used in so many ways, the capable in one sense will mean that which can begin a movement (or a change in general, for even that which can bring things to rest is a capable thing) in another thing or in itself qua other; and in one [1019b1] sense that over which something else has such a capacity; and in one sense that which has a capacity of changing into something, whether for the worse or for the better (for even that which perishes is thought to be capable of perishing, for it would not have perished if it has not been capable of it; but, as a matter of fact, it [5] has a certain disposition and cause and principle which fits it to suffer this;—sometimes it is thought to be of this sort because it has something, sometimes because it is deprived of something; but if privation is in a sense having, everything will be capable by having something, so that things are capable both by having something, i.e. a principle, and by having the privation of the positive principle, if it [10] is possible to have a privation; and if privation is not in a sense having, things are called capable homonymously); and a thing is capable in another sense because neither any other thing, nor itself qua other, has a capacity or principle which can destroy it. Again, all these are capable either merely because the thing might chance to happen or not to happen, or because it might do so well. This sort of capacity is found also in lifeless things, e.g. in instruments; for we say one lyre can be made to sound, and another cannot be made to sound at all, if it has not a good [15] tone.

  Incapacity is privation of capacity—i.e. of such a principle as has been described—either in general or in the case of something that would naturally have the capacity, or even at the time when it would naturally already have it; for the senses in which we should call a boy and a man and a eunuch incapable of begetting are distinct.—Again, to either kind of capacity there is a corresponding incapacity—both [20] to that which only can produce movement and to that which can produce it well.

  Some things, then, are called incapable in virtue of this kind of incapacity, while others are so in another sense, i.e. possible and impossible. The impossible is that of which the contrary is of necessity true, e.g. that the diagonal of a square is [25] commensurate with the side is impossible, because such a statement is a falsity such that not only is the contrary true but it is necessary; that it is commensurate, then, is not only false but of necessity false. The contrary of this, the possible, is found when it is not necessary that the contrary is false, e.g. that a man should be seated is [30] possible; for that he is not seated is not of necessity false.—The possible, then, in one sense, as has been said, means that which is not of necessity false; in another, that which is true; in another, that which is capable of being true.—A ‘capacity’4 in geometry is so called by extension of meaning.—These senses of ‘possible’ involve no reference to cap
acity. But the senses which involve a reference to capacity all [1020a1] refer to the primary kind of capacity; and this is a source of change in another thing or in the same thing qua other. For other things are called ‘capable’, some because something else has such a capacity over them, some because it has not, some because it has it in a particular way. The same is true of the things that are [5] incapable. Therefore the proper definition of the primary kind of capacity will be a source of change in another thing or in the same thing qua other.

  13 · We call a quantity that which is divisible into two or more constituent parts of which each is by nature a one and a ‘this’. A quantity is a plurality if it is numerable, a magnitude if it is measurable. We call a plurality that which is divisible potentially into non-continuous parts, a magnitude that which is divisible [10] into continuous parts; in magnitude, that which is continuous in one dimension is length, in two breadth, in three depth. Of these, limited plurality is number, limited length is a line, breadth a surface, depth a solid.

  Again, some things are called quantities in virtue of their own nature, others [15] accidentally, e.g. the line is a quantity by its own nature, the musical is one accidentally. Of the things that are quantities by their own nature some are so as substances, e.g. the line is a quantity (for a certain kind of quantity is present in the formula which states what it is), and others are modifications and states of this kind of substance, e.g. much and little, long and short, broad and narrow, deep and [20] shallow, heavy and light, and the other terms of this sort. And also great and small, and greater and smaller, both in themselves and when taken relatively to each other, are by their own nature attributes of quantity; but these names are transferred to [25] other things also. Of things that are quantities accidentally, some are so called in the sense in which it was said that musical and white were quantities, viz. because that to which they belong is a quantity, and some are quantities in the way in which movement and time are so; for these are called quantities and continuous because the things of which these are attributes are divisible. I mean not that which is [30] moved, but the space through which it is moved; for because that is a quantity movement also is a quantity, and because this is a quantity time is so.

  14 · We call a quality (1) the differentia of the substance, e.g. man is an animal of a certain quality because he is two-footed, and the horse is so because it is four-footed; and a circle is a figure of particular quality because it is without angles—which shows that the differentia with reference to substance is a [1020b1] quality.—This, then, is one meaning of quality—differentia of substance, but (2) there is another sense in which it applies to the unmovable objects of mathematics; i.e. the numbers have a certain quality, e.g. the composite numbers which are not in one dimension only, but of which the plane and the solid are copies (these are those [5] which have two or three factors); and in general that which exists in the substance of numbers besides quantity is quality; for the substance of each is what it is once, e.g. that of 6 is not what it is twice or thrice, but what it is once; for 6 is once 6.

  (3) All the attributes of substances in motion (e.g. heat and cold, whiteness and blackness, heaviness and lightness, and others of this sort), in virtue of which, [10] when they change, bodies are said to alter. (4) Quality in respect of excellence and badness and, in general, of good and bad.

  Quality, then, seems to have practically two meanings, and one of these is the more proper. The primary quality is the differentia of substance, and of this the [15] quality in numbers is a part; for it is a differentia of substances, but either not of things in motion or not of them qua in motion. Secondly, there are the modifications of things in motion qua in motion, and the differentiae of movements. Excellence and badness fall among these modifications; for they indicate differentiae of the [20] movement or activity, according to which the things in motion act or are acted on well or badly; for that which can be moved or act in one way is good, and that which can do so in another—the contrary—way is vicious. Good and bad indicate quality [25] especially in living things, and among these especially in those which have choice.

  15 · Things are relative (1) as double to half and treble to a third, and in general that which contains something else many times to that which is contained many times in something else, and that which exceeds to that which is exceeded; (2) as that which can heat to that which can be heated, and that which can cut to that [30] which can be cut, and in general the active to the passive; (3) as the measurable to the measure and the knowable to knowledge and the perceptible to perception.

  (1) Relative terms of the first kind are numerically related either indefinitely or definitely, either to various numbers or to 1, e.g. the double is in a definite numerical relation to 1, and that which is many times as great is in a numerical, but not in a definite, relation to 1, i.e. not in this or in that relation to it; the relation of [1021a1] that which is 3/2 of something else to its reciprocal is a definite numerical relation to a number; that which is 1 and a bit times something else is in an indefinite relation to its reciprocal, as that which is many times as great is in an indefinite relation to 1; the relation of that which exceeds to that which is exceeded is numerically quite [5] indefinite; for number is always commensurable, and number is not said of the non-commensurable; but that which exceeds is, in relation to that which is exceeded, so much and something more; and this something is indefinite; for it can, indifferently, be either equal or not equal to that which is exceeded.—All these relations are numerically expressed and are determinations of number, and so in [10] another way are the equal and the like and the same, for all refer to unity. Those things are the same whose substance is one; those are like whose quality is one; those are equal whose quantity is one; and 1 is the beginning and measure of number, so that all these relations imply number, though not in the same way.

  [15] (2) The active and the passive imply an active and a passive capacity and the actualization of the capacities, e.g. that which is capable of heating is related to that which is capable of being heated, because it can heat it, and, again, that which is heating is related to that which is being heated and that which is cutting to that which is being cut, because they are actually doing these things. But numerical relations are not actualized except in the sense which has been elsewhere stated; [20] actualizations in the sense of movement they have not. Of relations which imply capacity some further imply particular periods of time, e.g. that which has made is relative to that which has been made and that which will make to that which will be made. For it is in this way that a father is called father of his son; for the one has acted, and the other has been acted on in a certain way. Further, some relative [25] terms imply privation of capacity, i.e. ‘incapable’ and terms of this sort, e.g. ‘invisible’.

  Relative terms which imply number or capacity, therefore, are all relative because their very essence includes in its nature a reference to something else, not because something else is related to it; but (3) that which is measurable or knowable or thinkable is called relative because something else is related to it. For the [30] thinkable implies that there is thought of it, but the thought is not relative to that of which it is the thought; for we should then have said the same thing twice. Similarly sight is the sight of something, not of that of which it is the sight (though of course it [1021b1] is true to say this); in fact it is relative to colour or to something else of the sort. But according to the other way of speaking the same thing would be said twice—‘it is the sight of that which is the object of sight’.

  Things that are by their own nature called relative are called so sometimes in these senses, sometimes because the classes that include them are of this sort, e.g. medicine is thought to be relative because its genus, knowledge, is thought to be [5] relative. Further, there are the properties in virtue of which the things that have them are called relative, e.g. equality is relative because the equal is, and likeness because the like is. Other things are relative by accident, e.g. a man
is relative because he happens to be double of something and double is a relative term; or the [10] white is relative, if the same thing happens to be double and white.

  16 · We call complete (1) that outside which it is not possible to find even one of the parts proper to it, e.g. the complete time of each thing is that outside which it is not possible to find any time which is a part proper to it.—(2) That which in respect of excellence and goodness cannot be excelled in its kind, e.g. a doctor is [15] complete and a flute-player is complete, when they lack nothing in respect of their proper kind of excellence. And thus we transfer the word to bad things, and speak of a complete scandal-monger and a complete thief; indeed we even call them good, i.e. a good thief and a good scandal-monger. And excellence is a completion; for each [20] thing is complete and every substance is complete, when in respect of its proper kind of excellence it lacks no part of its natural magnitude.—(3) The things which have attained a good end are called complete; for things are complete in virtue of having attained their end. Therefore, since the end is something ultimate, we transfer the [25] word to bad things and say a thing has been completely spoilt, and completely destroyed, when it in no way falls short of destruction and badness, but is at its last point. This is why death is by a figure of speech called the end, because both are last things. The ultimate thing for the sake of which is also an end.—Things, then, that [30] are called complete in virtue of their own nature are so called in all these senses, some because they lack nothing in respect of goodness and cannot be excelled and no part proper to them can be found outside, others in general because they cannot be exceeded in their several classes and no part proper to them is outside; the others are so called in virtue of these first two kinds, because they either make or have [1022a1] something of the sort or are adapted to it or in some way or other are referred to the things that are called complete in the primary sense.