The Basic Works of Aristotle (Modern Library Classics) Read online

  Of species themselves, except in the case of such as are genera, no one is more truly substance than another. We should not give a more appropriate account of the individual man by stating the species to which he belonged, (25) than we should of an individual horse by adopting the same method of definition. In the same way, of primary substances, no one is more truly substance than another; an individual man is not more truly substance than an individual ox.

  It is, then, with good reason that of all that remains, when we exclude primary substances, we concede to species and genera alone the name ‘secondary substance’, (30) for these alone of all the predicates convey a knowledge of primary substance. For it is by stating the species or the genus that we appropriately define any individual man; and we shall make our definition more exact by stating the former than by stating the latter. All other things that we state, such as that he is white, (35) that he runs, and so on, are irrelevant to the definition. Thus it is just that these alone, apart from primary substances, should be called substances.

  Further, primary substances are most properly so called, because they underlie and are the subjects of everything else. [3a] Now the same relation that subsists between primary substance and everything else subsists also between the species and the genus to which the primary substance belongs, on the one hand, and every attribute which is not included within these, on the other. For these are the subjects of all such. If we call an individual man ‘skilled in grammar’, the predicate is applicable also to the species and to the genus to which he belongs. (5) This law holds good in all cases.

  It is a common characteristic of all substance that it is never present in a subject. For primary substance is neither present in a subject nor predicated of a subject; while, with regard to secondary substances, it is clear from the following arguments (apart from others) that they are not present in a subject. For ‘man’ is predicated of the individual man, but is not present in any subject: (10) for manhood is not present in the individual man. In the same way, ‘animal’ is also predicated of the individual man, but is not present in him. Again, when a thing is present in a subject, though the name may quite well be applied to that in which it is present, (15) the definition cannot be applied. Yet of secondary substances, not only the name, but also the definition, applies to the subject: we should use both the definition of the species and that of the genus with reference to the individual man. (20) Thus substance cannot be present in a subject.

  Yet this is not peculiar to substance, for it is also the case that differentiae cannot be present in subjects. The characteristics ‘terrestrial’ and ‘two-footed’ are predicated of the species ‘man’, but not present in it. For they are not in man. Moreover, (25) the definition of the differentia may be predicated of that of which the differentia itself is predicated. For instance, if the characteristic ‘terrestrial’ is predicated of the species ‘man’, the definition also of that characteristic may be used to form the predicate of the species ‘man’: for ‘man’ is terrestrial.

  The fact that the parts of substances appear to be present in the whole, as in a subject, should not make us apprehensive lest we should have to admit that such parts are not substances: (30) for in explaining the phrase ‘being present in a subject’, we stated that we meant ‘otherwise than as parts in a whole’.1

  It is the mark of substances and of differentiae that, in all propositions of which they form the predicate, they are predicated univocally. For all such propositions have for their subject either the individual or the species. It is true that, inasmuch as primary substance is not predicable of anything, (35) it can never form the predicate of any proposition. But of secondary substances, the species is predicated of the individual, the genus both of the species and of the individual. Similarly the differentiae are predicated of the species and of the individuals. [3b] Moreover, the definition of the species and that of the genus are applicable to the primary substance, and that of the genus to the species. For all that is predicated of the predicate will be predicated also of the subject. Similarly, (5) the definition of the differentiae will be applicable to the species and to the individuals. But it was stated above that the word ‘univocal’ was applied to those things which had both name and definition in common.2 It is, therefore, established that in every proposition, of which either substance or a differentia forms the predicate, these are predicated univocally.

  All substance appears to signify that which is individual. (10) In the case of primary substance this is indisputably true, for the thing is a unit. In the case of secondary substances, when we speak, for instance, of ‘man’ or ‘animal’, our form of speech gives the impression that we are here also indicating that which is individual, but the impression is not strictly true; (15) for a secondary substance is not an individual, but a class with a certain qualification; for it is not one and single as a primary substance is; the words ‘man’, ‘animal’, are predicable of more than one subject.

  Yet species and genus do not merely indicate quality, like the term ‘white’; ‘white’ indicates quality and nothing further, but species and genus determine the quality with reference to a substance: they signify substance qualitatively differentiated. (20) The determinate qualification covers a larger field in the case of the genus than in that of the species: he who uses the word ‘animal’ is herein using a word of wider extension than he who uses the word ‘man’.

  Another mark of substance is that it has no contrary. What could be the contrary of any primary substance, (25) such as the individual man or animal? It has none. Nor can the species or the genus have a contrary. Yet this characteristic is not peculiar to substance, but is true of many other things, such as quantity. There is nothing that forms the contrary of ‘two cubits long’ or of ‘three cubits long’, or of ‘ten’, or of any such term. (30) A man may contend that ‘much’ is the contrary of ‘little’, or ‘great’ of ‘small’, but of definite quantitative terms no contrary exists.

  Substance, again, does not appear to admit of variation of degree. I do not mean by this that one substance cannot be more or less truly substance than another, for it has already been stated3 that this is the case; (35) but that no single substance admits of varying degrees within itself. For instance, one particular substance, ‘man’, cannot be more or less man either than himself at some other time or than some other man. One man cannot be more man than another, as that which is white may be more or less white than some other white object, or as that which is beautiful may be more or less beautiful than some other beautiful object. [4a] The same quality, moreover, is said to subsist in a thing in varying degrees at different times. A body, being white, is said to be whiter at one time than it was before, or, being warm, is said to be warmer or less warm than at some other time. But substance is not said to be more or less that which it is: (5) a man is not more truly a man at one time than he was before, nor is anything, if it is substance, more or less what it is. Substance, then, does not admit of variation of degree.

  The most distinctive mark of substance appears to be that, (10) while remaining numerically one and the same, it is capable of admitting contrary qualities. From among things other than substance, we should find ourselves unable to bring forward any which possessed this mark. Thus, one and the same colour cannot be white and black. (15) Nor can the same one action be good and bad: this law holds good with everything that is not substance. But one and the self-same substance, while retaining its identity, is yet capable of admitting contrary qualities. The same individual person is at one time white, at another black, at one time warm, at another cold, at one time good, (20) at another bad. This capacity is found nowhere else, though it might be maintained that a statement or opinion was an exception to the rule. The same statement, it is agreed, can be both true and false. For if the statement ‘he is sitting’ is true, yet, (25) when the person in question has risen, the same statement will be false. The same applies to opinions. For if any one thinks truly that a person is sitting, yet,
when that person has risen, this same opinion, if still held, will be false. Yet although this exception may be allowed, there is, nevertheless, a difference in the manner in which the thing takes place. It is by themselves changing that substances admit contrary qualities. (30) It is thus that that which was hot becomes cold, for it has entered into a different state. Similarly that which was white becomes black, and that which was bad good, by a process of change; and in the same way in all other cases it is by changing that substances are capable of admitting contrary qualities. But statements and opinions themselves remain unaltered in all respects: it is by the alteration in the facts of the case that the contrary quality comes to be theirs. (35) The statement ‘he is sitting’ remains unaltered, but it is at one time true, at another false, according to circumstances. [4b] What has been said of statements applies also to opinions. Thus, in respect of the manner in which the thing takes place, it is the peculiar mark of substance that it should be capable of admitting contrary qualities; for it is by itself changing that it does so.

  If, then, a man should make this exception and contend that statements and opinions are capable of admitting contrary qualities, his contention is unsound. For statements and opinions are said (5) to have this capacity, not because they themselves undergo modification, but because this modification occurs in the case of something else. The truth or falsity of a statement depends on facts, and not on any power on the part of the statement itself of admitting contrary qualities. (10) In short, there is nothing which can alter the nature of statements and opinions. As, then, no change takes place in themselves, these cannot be said to be capable of admitting contrary qualities.

  But it is by reason of the modification which takes place within the substance itself that a substance is said to be capable of admitting contrary qualities; for a substance admits within itself either disease or health, (15) whiteness or blackness. It is in this sense that it is said to be capable of admitting contrary qualities.

  To sum up, it is a distinctive mark of substance, that, while remaining numerically one and the same, it is capable of admitting contrary qualities, the modification taking place through a change in the substance itself.

  Let these remarks suffice on the subject of substance.

  6 Quantity is either discrete or continuous. (20) Moreover, some quantities are such that each part of the whole has a relative position to the other parts: others have within them no such relation of part to part.

  Instances of discrete quantities are number and speech; of continuous, lines, surfaces, solids, and, besides these, time and place.

  In the case of the parts of a number, (25) there is no common boundary at which they join. For example: two fives make ten, but the two fives have no common boundary, but are separate; the parts three and seven also do not join at any boundary. Nor, to generalize, would it ever be possible in the case of number that there should be a common boundary among the parts; (30) they are always separate. Number, therefore, is a discrete quantity.

  The same is true of speech. That speech is a quantity is evident: for it is measured in long and short syllables. I mean here that speech which is vocal. Moreover, it is a discrete quantity, for its parts have no common boundary. (35) There is no common boundary at which the syllables join, but each is separate and distinct from the rest.

  [5a] A line, on the other hand, is a continuous quantity, for it is possible to find a common boundary at which its parts join. In the case of the line, this common boundary is the point; in the case of the plane, it is the line: for the parts of the plane have also a common boundary. Similarly you can find a common boundary in the case of the parts of a solid, (5) namely either a line or a plane.

  Space and time also belong to this class of quantities. Time, past, present, and future, forms a continuous whole. Space, likewise, is a continuous quantity: for the parts of a solid occupy a certain space, and these have a common boundary; it follows that the parts of space also, which are occupied by the parts of the solid, (10) have the same common boundary as the parts of the solid. Thus, not only time, but space also, is a continuous quantity, for its parts have a common boundary.

  Quantities consist either of parts which bear a relative position each to each, (15) or of parts which do not. The parts of a line bear a relative position to each other, for each lies somewhere, and it would be possible to distinguish each, and to state the position of each on the plane and to explain to what sort of part among the rest each was contiguous. Similarly the parts of a plane have position, (20) for it could similarly be stated what was the position of each and what sort of parts were contiguous. The same is true with regard to the solid and to space. But it would be impossible to show that the parts of a number had a relative position each to each, or a particular position, (25) or to state what parts were contiguous. Nor could this be done in the case of time, for none of the parts of time has an abiding existence, and that which does not abide can hardly have position. It would be better to say that such parts had a relative order, in virtue of one being prior to another. Similarly with number: in counting, ‘one’ is prior to ‘two’, and ‘two’ to ‘three’, (30) and thus the parts of number may be said to possess a relative order, though it would be impossible to discover any distinct position for each. This holds good also in the case of speech. None of its parts has an abiding existence: when once a syllable is pronounced, it is not possible to retain it, so that, naturally, as the parts do not abide, (35) they cannot have position. Thus, some quantities consist of parts which have position, and some of those which have not.

  Strictly speaking, only the things which I have mentioned belong to the category of quantity: everything else that is called quantitative is a quantity in a secondary sense. It is because we have in mind some one of these quantities, properly so called, that we apply quantitative terms to other things. [5b] We speak of what is white as large, because the surface over which the white extends is large; we speak of an action or a process as lengthy, because the time covered is long; these things cannot in their own right claim the quantitative epithet. For instance, should any one explain how long an action was, his statement would be made in terms of the time taken, (5) to the effect that it lasted a year, or something of that sort. In the same way, he would explain the size of a white object in terms of surface, for he would state the area which it covered. Thus the things already mentioned, and these alone, are in their intrinsic nature quantities; nothing else can claim the name in its own right, (10) but, if at all, only in a secondary sense.

  Quantities have no contraries. In the case of definite quantities this is obvious; thus, there is nothing that is the contrary of ‘two cubits long’ or of ‘three cubits long’, or of a surface, or of any such quantities. A man might, indeed, argue that ‘much’ was the contrary of ‘little’, (15) and ‘great’ of ‘small’. But these are not quantitative, but relative; things are not great or small absolutely, they are so called rather as the result of an act of comparison. For instance, a mountain is called small, a grain large, in virtue of the fact that the latter is greater than others of its kind, the former less. (20) Thus there is a reference here to an external standard, for if the terms ‘great’ and ‘small’ were used absolutely, a mountain would never be called small or a grain large. Again, we say that there are many people in a village, and few in Athens, although those in the city are many times as numerous as those in the village: or we say that a house has many in it, (25) and a theatre few, though those in the theatre far outnumber those in the house. The terms ‘two cubits long’, ‘three cubits long’, and so on indicate quantity, the terms ‘great’ and ‘small’ indicate relation, for they have reference to an external standard. It is, therefore, plain that these are to be classed as relative.

  Again, (30) whether we define them as quantitative or not, they have no contraries: for how can there be a contrary of an attribute which is not to be apprehended in or by itself, but only by reference to something external? Again, if ‘great’ and �
�small’ are contraries, it will come about that the same subject can admit contrary qualities at one and the same time, and that things will themselves be contrary to themselves. (35) For it happens at times that the same thing is both small and great. For the same thing may be small in comparison with one thing, and great in comparison with another, so that the same thing comes to be both small and great at one and the same time, and is of such a nature as to admit contrary qualities at one and the same moment. Yet it was agreed, when substance was being discussed, that nothing admits contrary qualities at one and the same moment. [6a] For though substance is capable of admitting contrary qualities, yet no one is at the same time both sick and healthy, nothing is at the same time both white and black. Nor is there anything which is qualified in contrary ways at one and the same time.

  Moreover, if these were contraries, they would themselves be contrary to themselves. For if ‘great’ is the contrary of ‘small’, (5) and the same thing is both great and small at the same time, then ‘small’ or ‘great’ is the contrary of itself. But this is impossible. The term ‘great’, therefore, is not the contrary of the term ‘small’, nor ‘much’ of ‘little’. And even though a man should call these terms not relative, but quantitative, they would not have contraries. (10)

  It is in the case of space that quantity most plausibly appears to admit of a contrary. For men define the term ‘above’ as the contrary of ‘below’, when it is the region at the centre they mean by ‘below’; and this is so, because nothing is farther from the extremities of the universe than the region at the centre. Indeed, (15) it seems that in defining contraries of every kind men have recourse to a spatial metaphor, for they say that those things are contraries which, within the same class, are separated by the greatest possible distance.