All the causes now mentioned fall under four senses which are the most obvious. For the letters are the cause of syllables, and the material is the cause of manufactured things, and fire and earth and all such things are the causes of bodies, and the parts are causes of the whole, and the hypotheses are causes of the conclusion, (20) in the sense that they are that out of which these respectively are made; but of these some are cause as the substratum (e. g. the parts), others as the essence (the whole, the synthesis, and the form). The semen, the physician, the adviser, and in general the agent, are all sources of change or of rest. The remainder are causes as the end and the good of the other things; for that for the sake of which other things are tends to be the best and the end of the other things; let us take it as making no difference whether we call it good or apparent good. (25)
These, then, are the causes, and this is the number of their kinds, but the varieties of causes are many in number, though when summarized these also are comparatively few. Causes are spoken of in many senses, (30) and even of those which are of the same kind some are causes in a prior and others in a posterior sense, e. g. both ‘the physician’ and ‘the professional man’ are causes of health, and both ‘the ratio 2:1’ and ‘number’ are causes of the octave, and the classes that include any particular cause are always causes of the particular effect. Again, there are accidental causes and the classes which include these; e. g. while in one sense ‘the sculptor’ causes the statue, (35) in another sense ‘Polyclitus’ causes it, because the sculptor happens to be Polyclitus; and the classes that include the accidental cause are also causes, e. g. ‘man’—or in general ‘animal’—is the cause of the statue, because Polyclitus is a man, and man is an animal. [1014a] (5) Of accidental causes also some are more remote or nearer than others, as, for instance, if ‘the white’ and ‘the musical’ were called causes of the statue, and not only ‘Polyclitus’ or ‘man’. But besides all these varieties of causes, whether proper or accidental, some are called causes as being able to act, others as acting; e. g. the cause of the house’s being built is a builder, or a builder who is building. (10)—The same variety of language will be found with regard to the effects of causes; e. g. a thing may be called the cause of this statue or of a statue or in general of an image, and of this bronze or of bronze or of matter in general; and similarly in the case of accidental effects. Again, both accidental and proper causes may be spoken of in combination; e. g. we may say not ‘Polyclitus’ nor ‘the sculptor’, but ‘Polyclitus the sculptor’.
Yet all these are but six in number, (15) while each is spoken of in two ways; for (A) they are causes either as the individual, or as the genus, or as the accidental, or as the genus that includes the accidental, and these either as combined, or as taken simply; and (B) all may be taken as acting or as having a capacity. (20) But they differ inasmuch as the acting causes, i. e. the individuals, exist, or do not exist, simultaneously with the things of which they are causes, e. g. this particular man who is healing, with this particular man who is recovering health, and this particular builder with this particular thing that is being built; but the potential causes are not always in this case; for the house does not perish at the same time as the builder. (25)
3 ‘Element’ means (1) the primary component immanent in a thing, and indivisible in kind into other kinds; e. g. the elements of speech are the parts of which speech consists and into which it is ultimately divided, while they are no longer divided into other forms of speech different in kind from them. (30) If they are divided, their parts are of the same kind, as a part of water is water (while a part of the syllable is not a syllable). Similarly those who speak of the elements of bodies mean the things into which bodies are ultimately divided, while they are no longer divided into other things differing in kind; and whether the things of this sort are one or more, (35) they call these elements. The so-called elements of geometrical proofs, and in general the elements of demonstrations, have a similar character; for the primary demonstrations, each of which is implied in many demonstrations, are called elements of demonstrations; and the primary syllogisms, which have three terms and proceed by means of one middle, are of this nature. [1014b] (2) People also transfer the word ‘element’ from this meaning and apply it to that which, being one and small, is useful for many purposes; for which reason what is small and simple and indivisible is called an element. (5) Hence come the facts that the most universal things are elements (because each of them being one and simple is present in a plurality of things, either in all or in as many as possible), and that unity and the point are thought by some to be first principles. Now, since the so-called genera are universal and indivisible (for there is no definition of them), some say the genera are elements, (10) and more so than the differentia, because the genus is more universal; for where the differentia is present, the genus accompanies it, but where the genus is present, the differentia is not always so. It is common to all the meanings that the element of each thing is the first component immanent in each. (15)
4 ‘Nature’ means (1) the genesis of growing things—the meaning which would be suggested if one were to pronounce the y in physis long.1 (2) That immanent part of a growing thing, from which its growth first proceeds. (3) The source from which the primary movement in each natural object is present in it in virtue of its own essence. (20) Those things are said to grow which derive increase from something else by contact and either by organic unity, or by organic adhesion as in the case of embryos. Organic unity differs from contact; for in the latter case there need not be anything besides the contact, but in organic unities there is something identical in both parts, which makes them grow together instead of merely touching, (25) and be one in respect of continuity and quantity, though not of quality.—(4) ‘Nature’ means the primary material of which any natural object consists or out of which it is made, which is relatively unshaped and cannot be changed from its own potency, as e. g. bronze is said to be the nature of a statue and of bronze utensils, and wood the nature of wooden things; and so in all other cases; for when a product is made out of these materials, (30) the first matter is preserved throughout. For it is in this way that people call the elements of natural objects also their nature, some naming fire, others earth, others air, others water, others something else of the sort, (35) and some naming more than one of these, and others all of them.—(5) ‘Nature’ means the essence of natural objects, as with those who say the nature is the primary mode of composition, or as Empedocles says:— [1015a]
Nothing that is has a nature,
But only mixing and parting of the mixed,
And nature is but a name given them by men.
Hence as regards the things that are or come to be by nature, though that from which they naturally come to be or are is already present, we say they have not their nature yet, (5) unless they have their form or shape. That which comprises both of these2 exists by nature, e. g. the animals and their parts; and not only is the first matter nature (and this in two senses, either the first, counting from the thing, or the first in general; e. g. in the case of works in bronze, bronze is first with reference to them, but in general perhaps water is first, if all things that can be melted are water), but also the form or essence, (10) which is the end of the process of becoming.—(6) By an extension of meaning from this sense of ‘nature’ every essence in general has come to be called a ‘nature’, because the nature of a thing is one kind of essence.
From what has been said, then, it is plain that nature in the primary and strict sense is the essence of things which have in themselves, (15) as such, a source of movement; for the matter is called the nature because it is qualified to receive this, and processes of becoming and growing are called nature because they are movements proceeding from this. And nature in this sense is the source of the movement of natural objects, being present in them somehow, either potentially or in complete reality.
5 We call ‘necessary’ (1) (a) that without which, (20) as a condition, a
thing cannot live; e. g. breathing and food are necessary for an animal; for it is incapable of existing without these; (b) the conditions without which good cannot be or come to be, or without which we cannot get rid or be freed of evil; e. g. drinking the medicine is necessary in order that we may be cured of disease, (25) and a man’s sailing to Aegina is necessary in order that he may get his money.—(2) The compulsory and compulsion, i. e. that which impedes and tends to hinder, contrary to impulse and purpose. For the compulsory is called necessary (whence the necessary is painful, as Evenus says: ‘For every necessary thing is ever irksome’), and compulsion is a form of necessity, (30) as Sophocles says: ‘But force necessitates me to this act.’ And necessity is held to be something that cannot be persuaded—and rightly, for it is contrary to the movement which accords with purpose and with reasoning.—(3) We say that that which cannot be otherwise is necessarily as it is. And from this sense of ‘necessary’ all the others are somehow derived; for a thing is said to do or suffer what is necessary in the sense of compulsory, (35) only when it cannot act according to its impulse because of the compelling force—which implies that necessity is that because of which a thing cannot be otherwise; and similarly as regards the conditions of life and of good; for when in the one case good, in the other life and being, are not possible without certain conditions, (5) these are necessary, and this kind of cause is a sort of necessity. [1015b] Again, demonstration is a necessary thing because the conclusion cannot be otherwise, if there has been demonstration in the unqualified sense; and the causes of this necessity are the first premisses, i. e. the fact that the propositions from which the syllogism proceeds cannot be otherwise.
Now some things owe their necessity to something other than themselves; others do not, but are themselves the source of necessity in other things. (10) Therefore the necessary in the primary and strict sense is the simple; for this does not admit of more states than one, so that it cannot even be in one state and also in another; for if it did it would already be in more than one. If, then, there are any things that are eternal and unmovable, nothing compulsory or against their nature attaches to them. (15)
6 ‘One’ means (1) that which is one by accident, (2) that which is one by its own nature. (1) Instances of the accidentally one are ‘Coriscus and what is musical’, and ‘musical Coriscus’ (for it is the same thing to say ‘Coriscus and what is musical’, and ‘musical Coriscus’), and ‘what is musical and what is just’, and ‘musical Coriscus and just Coriscus’. For all of these are called one by virtue of an accident, (20) ‘what is just and what is musical’ because they are accidents of one substance, ‘what is musical and Coriscus’ because the one is an accident of the other; and similarly in a sense ‘musical Coriscus’ is one with ‘Coriscus’ because one of the parts of the phrase is an accident of the other, (25) i. e. ‘musical’ is an accident of Coriscus; and ‘musical Coriscus’ is one with ‘just Coriscus’ because one part of each is an accident of one and the same subject. The case is similar if the accident is predicated of a genus or of any universal name, e. g. if one says that man is the same as ‘musical man’; for this is either because ‘musical’ is an accident of man, (30) which is one substance, or because both are accidents of some individual, e. g. Coriscus. Both, however, do not belong to him in the same way, but one presumably as genus and included in his substance, the other as a state or affection of the substance.
The things, (35) then, that are called one in virtue of an accident, are called so in this way. (2) Of things that are called one in virtue of their own nature some (a) are so called because they are continuous, e. g. a bundle is made one by a band, and pieces of wood are made one by glue; and a line, even if it is bent, is called one if it is continuous, as each part of the body is, e. g. the leg or the arm. [1016a] Of these themselves, the continuous by nature are more one than the continuous by art. (5) A thing is called continuous which has by its own nature one movement and cannot have any other; and the movement is one when it is indivisible, and it is indivisible in respect of time. Those things are continuous by their own nature which are one not merely by contact; for if you put pieces of wood touching one another, you will not say these are one piece of wood or one body or one continuum of any other sort. Things, then, that are continuous in any way are called one, (10) even if they admit of being bent, and still more those which cannot be bent; e. g. the shin or the thigh is more one than the leg, because the movement of the leg need not be one. And the straight line is more one than the bent; but that which is bent and has an angle we call both one and not one, because its movement may be either simultaneous or not simultaneous; but that of the straight line is always simultaneous, (15) and no part of it which has magnitude rests while another moves, as in the bent line.
(b) (i) Things are called one in another sense because their substratum does not differ in kind; it does not differ in the case of things whose kind is indivisible to sense. The substratum meant is either the nearest to, (20) or the farthest from, the final state. For, on the one hand, wine is said to be one and water is said to be one, qua indivisible in kind; and, on the other hand, all juices, e. g. oil and wine, are said to be one, and so are all things that can be melted, because the ultimate substratum of all is the same; for all of these are water or air.
(ii) Those things also are called one whose genus is one though distinguished by opposite differentiae—these too are all called one because the genus which underlies the differentiae is one (e. g. horse, (25) man, and dog form a unity, because all are animals), and indeed in a way similar to that in which the matter is one. These are sometimes called one in this way, but sometimes it is the higher genus that is said to be the same (if they are infimae species of their genus)—the genus above the proximate genera; e. g. the isosceles and the equilateral are one and the same figure because both are triangles; but they are not the same triangles. (30)
(c) Two things are called one, when the definition which states the essence of one is indivisible from another definition which shows us the other (though in itself every definition is divisible). (35) Thus even that which has increased or is diminishing is one, because its definition is one, as, in the case of plane figures, is the definition of their form. [1016b] In general those things the thought of whose essence is indivisible, and cannot separate them either in time or in place or in definition, are most of all one, and of these especially those which are substances. For in general those things that do not admit of division are called one in so far as they do not admit of it; e. g. if two things are indistinguishable qua man, (5) they are one kind of man; if qua animal, one kind of animal; if qua magnitude, one kind of magnitude.—Now most things are called one because they either do or have or suffer or are related to something else that is one, but the things that are primarily called one are those whose substance is one—and one either in continuity or in form or in definition; for we count as more than one either things that are not continuous, or those whose form is not one, (10) or those whose definition is not one.
While in a sense we call anything one if it is a quantity and continuous, in a sense we do not unless it is a whole, i. e. unless it has unity of form; e. g. if we saw the parts of a shoe put together anyhow we should not call them one all the same (unless because of their continuity); we do this only if they are put together so as to be a shoe and to have already a certain single form. (15) This is why the circle is of all lines most truly one, because it is whole and complete.
(3) The essence of what is one is to be some kind of beginning of number; for the first measure is the beginning, since that by which we first know each class is the first measure of the class; the one, then, (20) is the beginning of the knowable regarding each class. But the one is not the same in all classes. For here it is a quarter-tone, and there it is the vowel or the consonant; and there is another unit of weight and another of movement. But everywhere the one is indivisible either in quantity or in kind. Now that which is indivisible in quantity is called a unit if i
t is not divisible in any dimension and is without position, (25) a point if it is not divisible in any dimension, and has position, a line if it is divisible in one dimension, a plane if in two, a body if divisible in quantity in all—i. e. in three—dimensions. And, reversing the order, that which is divisible in two dimensions is a plane, that which is divisible in one a line, that which is in no way divisible in quantity is a point or a unit—that which has not position a unit, (30) that which has position a point.
Again, some things are one in number, others in species, others in genus, others by analogy; in number those whose matter is one, in species those whose definition is one, in genus those to which the same figure of predication applies,3 by analogy those which are related as a third thing is to a fourth. (35) The latter kinds of unity are always found when the former are; e. g. things that are one in number are also one in species, while things that are one in species are not all one in number; but things that are one in species are all one in genus, while things that are so in genus are not all one in species but are all one by analogy; while things that are one by analogy are not all one in genus. [1017a]
Evidently ‘many’ will have meanings opposite to those of ‘one’; some things are many because they are not continuous, (5) others because their matter—either the proximate matter or the ultimate—is divisible in kind, others because the definitions which state their essence are more than one.
The Basic Works of Aristotle (Modern Library Classics) Page 105