(1) With respect to your inquiry, “ what the peculiarities are in each of the more excellent genera, by which they are separated from each other? ” if you understand by peculiarities the specific differences under the same genus, which are distinguished by opposite qualities, as the rational and irrational under animal; we by no means admit peculiarities of this kind, in things which neither have one common essence, nor an equal contradistinction, nor receive a composition from something common, which is indefinite, and defines the peculiarity. But if you apprehend the peculiarity to be, as in prior and secondary natures, differing in their whole essence and whole genus, a certain simple condition of being, definite in itself; in this case, your conception of peculiarities will be reasonable. For these peculiarities of things, which have an eternal subsistence, are simple, and entirely exempt. The inquiry, however, proceeds imperfectly. For it was necessary, in the first place, to inquire what the peculiarities are of the more excellent genera, according to essence; in the next place, what they are according to power; and thus afterwards, what they are according to energy.

(19) Having established our four primary genera, it remains for us to enquire whether each of them of itself alone produces species. And especially, can Being be divided independently, that is without drawing upon the other genera? Surely not: the differentiae must come from outside the genus differentiated: they must be differentiae of Being proper, but cannot be identical with it.

Where then is it to find them? Obviously not in non-beings. If then in beings, and the three genera are all that is left, clearly it must find them in these, by conjunction and couplement with these, which will come into existence simultaneously with itself.

But if all come into existence simultaneously, what else is produced but that amalgam of all Existents which we have just considered ? How can other things exist over and above this all-including amalgam? And if all the constituents of this amalgam are genera, how do they produce species? How does Motion produce species of Motion? Similarly with Stability and the other genera.

A word of warning must here be given against sinking the various genera in their species; and also against reducing the genus to a mere predicate, something merely seen in the species. The genus must exist at once in itself and in its species; it blends, but it must also be pure; in contributing along with other genera to form Substance, it must not destroy itself. There are problems here that demand investigation.

But since we identified the amalgam of the Existents with the particular intellect, Intellect as such being found identical with Being or Substance, and therefore prior to all the Existents, which may be regarded as its species or members, we may infer that the intellect, considered as completely unfolded, is a subsequent.

Our treatment of this problem may serve to promote our investigation; we will take it as a kind of example, and with it embark upon our enquiry.

(9) The above considerations- to which others, doubtless, might be added- suffice to show that these five are primary genera. But that they are the only primary genera, that there are no others, how can we be confident of this? Why do we not add unity to them? Quantity? Quality? Relation, and all else included by our various forerunners?

As for unity: If the term is to mean a unity in which nothing else is present, neither Soul nor Intellect nor anything else, this can be predicated of nothing, and therefore cannot be a genus. If it denotes the unity present in Being, in which case we predicate Being of unity, this unity is not primal.

Besides, unity, containing no differences, cannot produce species, and not producing species, cannot be a genus. You cannot so much as divide unity: to divide it would be to make it many. Unity, aspiring to be a genus, becomes a plurality and annuls itself.

Again, you must add to it to divide it into species; for there can be no differentiae in unity as there are in Substance. The mind accepts differences of Being, but differences within unity there cannot be. Every differentia introduces a duality destroying the unity; for the addition of any one thing always does away with the previous quantity.

It may be contended that the unity which is implicit in Being and in Motion is common to all other things, and that therefore Being and unity are inseparable. But we rejected the idea that Being is a genus comprising all things, on the ground that these things are not beings in the sense of the Absolute Being, but beings in another mode: in the same way, we assert, unity is not a genus, the Primary Unity having a character distinct from all other unities.

Admitted that not everything suffices to produce a genus, it may yet be urged that there is an Absolute or Primary Unity corresponding to the other primaries. But if Being and unity are identified, then since Being has already been included among the genera, it is but a name that is introduced in unity: if, however, they are both unity, some principle is implied: if there is anything in addition , unity is predicated of this added thing; if there is nothing added, the reference is again to that unity predicated of nothing. If however the unity referred to is that which accompanies Being, we have already decided that it is not unity in the primary sense.

But is there any reason why this less complete unity should not still possess Primary Being, seeing that even its posterior we rank as Being, and "Being" in the sense of the Primary Being? The reason is that the prior of this Being cannot itself be Being- or else, if the prior is Being, this is not Primary Being: but the prior is unity; .

Furthermore, unity, abstracted from Being, has no differentiae.

Again, even taking it as bound up with Being: If it is a consequent of Being, then it is a consequent of everything, and therefore the latest of things: but the genus takes priority. If it is simultaneous with Being, it is simultaneous with everything: but a genus is not thus simultaneous. If it is prior to Being, it is of the nature of a Principle, and therefore will belong only to Being; but if it serves as Principle to Being, it is not its genus: if it is not genus to Being, it is equally not a genus of anything else; for that would make Being a genus of all other things.

In sum, the unity exhibited in Being on the one hand approximates to Unity-Absolute and on the other tends to identify itself with Being: Being is a unity in relation to the Absolute, is Being by virtue of its sequence upon that Absolute: it is indeed potentially a plurality, and yet it remains a unity and rejecting division refuses thereby to become a genus.

(9) So much for one of the genera- the "Substance," so called, of the Sensible realm.

But what are we to posit as its species? how divide this genus?

The genus as a whole must be identified with body. Bodies may be divided into the characteristically material and the organic: the material bodies comprise fire, earth, water, air; the organic the bodies of plants and animals, these in turn admitting of formal differentiation.

The next step is to find the species of earth and of the other elements, and in the case of organic bodies to distinguish plants according to their forms, and the bodies of animals either by their habitations- on the earth, in the earth, and similarly for the other elements- or else as light, heavy and intermediate. Some bodies, we shall observe, stand in the middle of the universe, others circumscribe it from above, others occupy the middle sphere: in each case we shall find bodies different in shape, so that the bodies of the living beings of the heavens may be differentiated from those of the other elements.

Once we have classified bodies into the four species, we are ready to combine them on a different principle, at the same time intermingling their differences of place, form and constitution; the resultant combinations will be known as fiery or earthy on the basis of the excess or predominance of some one element.

The distinction between First and Second Substances, between Fire and a given example of fire, entails a difference of a peculiar kind- the difference between universal and particular. This however is not a difference characteristic of Substance; there is also in Quality the distinction between whiteness and the white object, between grammar and some particular grammar.

The question may here be asked: "What deficiency has grammar compared with a particular grammar, and science as a whole in comparison with a science?" Grammar is certainly not posterior to the particular grammar: on the contrary, the grammar as in you depends upon the prior existence of grammar as such: the grammar as in you becomes a particular by the fact of being in you; it is otherwise identical with grammar the universal.

Turn to the case of Socrates: it is not Socrates who bestows manhood upon what previously was not Man, but Man upon Socrates; the individual man exists by participation in the universal.

Besides, Socrates is merely a particular instance of Man; this particularity can have no effect whatever in adding to his essential manhood.

We may be told that Man is Form alone, Socrates Form in Matter. But on this very ground Socrates will be less fully Man than the universal; for the Reason-Principle will be less effectual in Matter. If, on the contrary, Man is not determined by Form alone, but presupposes Matter, what deficiency has Man in comparison with the material manifestation of Man, or the Reason-Principle in isolation as compared with its embodiment in a unit of Matter?

Besides, the more general is by nature prior; hence, the Form-Idea is prior to the individual: but what is prior by nature is prior unconditionally. How then can the Form take a lower rank? The individual, it is true, is prior in the sense of being more readily accessible to our cognisance; this fact, however, entails no objective difference.

Moreover, such a difference, if established, would be incompatible with a single Reason-Principle of Substance; First and Second Substance could not have the same Principle, nor be brought under a single genus.

(53) Hence comes discernment between things which are of like nature, not distinguished by difference of kind, character or position.

(3) We assert, then, a plurality of Existents, but a plurality not fortuitous and therefore a plurality deriving from a unity.

But even admitting this derivation from a unity- a unity however not predicated of them in respect of their essential being- there is, surely, no reason why each of these Existents, distinct in character from every other, should not in itself stand as a separate genus.

Is, then, this unity external to the genera thus produced, this unity which is their source though it cannot be predicated of them in respect of their essence? it is indeed external; the One is beyond; it cannot, therefore, be included among the geneANSWER: it is the source, while they stand side by side as genera. Yet surely the one must somehow be included ? No: it is the Existents we are investigating, not that which is beyond Existence.

We pass on, then, to consider that which is included, and find to our surprise the cause included with the things it causes: it is surely strange that causes and effects should be brought into the same genus.

But if the cause is included with its effects only in the sense in which a genus is included with its subordinates, the subordinates being of a different order, so that it cannot be predicated of them whether as their genus or in any other relation, these subordinates are obviously themselves genera with subordinates of their own: you may, for example, be the cause of the operation of walking, but the walking is not subordinate to you in the relation of species to genus; and if walking had nothing prior to it as its genus, but had posteriors, then it would be a genus and rank among the Existents.

Perhaps, however, it must be utterly denied that unity is even the cause of other things; they should be considered rather as its parts or elements- if the terms may be allowed,- their totality constituting a single entity which our thinking divides. All unity though it be, it goes by a wonderful power out into everything; it appears as many and becomes many when there is a motion; the fecundity of its nature causes the One to be no longer one, and we, displaying what we call its parts, consider them each as a unity and make them into "genera," unaware of our failure to see the whole at once. We display it, then, in parts, though, unable to restrain their natural tendency to coalesce, we bring these parts together again, resign them to the whole and allow them to become a unity, or rather to be a unity.

All this will become clearer in the light of further consideration- when, that is to say, we have ascertained the number of the genera; for thus we shall also discover their causes. It is not enough to deny; we must advance by dint of thought and comprehension. The way is clear:

(18) These problems at any rate all serve to show that, while in general it is necessary to look for differences by which to separate things from each other, to hunt for differences of the differences themselves is both futile and irrational. We cannot have substances of substances, quantities of quantities, qualities of qualities, differences of differences; differences must, where possible, be found outside the genus, in creative powers and the like: but where no such criteria are present, as in distinguishing dark-green from pale-green, both being regarded as derived from white and black, what expedient may be suggested?

Sense-perception and intelligence may be trusted to indicate diversity but not to explain it: explanation is outside the province of sense-perception, whose function is merely to produce a variety of information; while, as for intelligence, it works exclusively with intuitions and never resorts to explanations to justify them; there is in the movements of intelligence a diversity which separates one object from another, making further differentiation unnecessary.

Do all qualities constitute differentiae, or not? Granted that whiteness and colours in general and the qualities dependent upon touch and taste can, even while they remain species , become differentiae of other things, how can grammar and music serve as differentiae? Perhaps in the sense that minds may be distinguished as grammatical and musical, especially if the qualities are innate, in which case they do become specific differentiae.

It remains to decide whether there can be any differentia derived from the genus to which the differentiated thing belongs, or whether it must of necessity belong to another genus? The former alternative would produce differentiae of things derived from the same genus as the differentiae themselves- for example, qualities of qualities. Virtue and vice are two states differing in quality: the states are qualities, and their differentiae qualities- unless indeed it be maintained that the state undifferentiated is not a quality, that the differentia creates the quality.

But consider the sweet as beneficial, the bitter as injurious: then bitter and sweet are distinguished, not by Quality, but by Relation. We might also be disposed to identify the sweet with the thick, and the Pungent with the thin: "thick" however hardly reveals the essence but merely the cause of sweetness- an argument which applies equally to pungency.

We must therefore reflect whether it may be taken as an invariable rule that Quality is never a differentia of Quality, any more than Substance is a differentia of Substance, or Quantity of Quantity.

Surely, it may be interposed, five differs from three by two. No: it exceeds it by two; we do not say that it differs: how could it differ by a "two" in the "three"? We may add that neither can Motion differ from Motion by Motion. There is, in short, no parallel in any of the other genera.

In the case of virtue and vice, whole must be compared with whole, and the differentiation conducted on this basis. As for the differentia being derived from the same genus as themselves, namely, Quality, and from no other genus, if we proceed on the principle that virtue is bound up with pleasure, vice with lust, virtue again with the acquisition of food, vice with idle extravagance, and accept these definitions as satisfactory, then clearly we have, here too, differentiae which are not qualities.

(12) The fifth genus is that of the water, of which the Kar fish is the largest, and the Nemadu the least. 13, These five genera are apportioned out into two hundred and eighty-two species (sardak). 14. First are five species of goat, the ass-goat, the milch-goat, the mountain-goat, the fawn, and the common goat. 15. Second, five species of sheep, that with a tail, that which has no tail, the dog-sheep, the wether, and the Kûrisk sheep, a sheep whose horn is great; it possesses a grandeur like unto a horse, and they use it mostly for a steed (bâra), as it is said that Mânûskîhar kept a Kûrisk as a steed. 16. Third, two species of camel, the mountain one and that suitable for grazing; for one is fit to keep in the mountain, and one in the plain; they are one-humped and two-humped. 17. Fourth, fifteen species of ox, the white, mud-coloured, red, yellow, black, and dappled, the elk, the buffalo, the camel-leopard ox, the fish-chewing ox, the Fars ox, the Kagau, and other species of ox. 18. Fifth, eight species of horse, the Arab, the Persian, the mule, the ass, the wild ass (gôr), the hippopotamus (asp-i âvî), and other species of horse. 19. Sixth, ten species of dog, the shepherd's dog, the village-dog which is the house-protector, the blood-hound, the slender hound, the water-beaver which they call the water-dog, the fox, the ichneumon (râsu), the hedgehog which they call 'thorny-back,' the porcupine, and the civet-cat; of which, two species are those accustomed to burrows, one the fox and one the ichneumon; and those accustomed to jungle are such as the porcupine which has spines on its back, and the hedgehog which is similar. 20. Seventh, five species of the black hare; two are wild species, one dwelling in a burrow and one dwelling in the jungle. 21. Eighth, eight species of weasel; one the marten, one the black marten, the squirrel, the Bez ermine, the white ermine, and other species of weasel. 22. Ninth, eight species of musk animals; one is that which is recognised by its musk, one the musk animal with a bag in which is their pleasant scent, the Bis-musk which eats the Bis-herb, the black musk which is the enemy of the serpent that is numerous in rivers, and other species of musk animals. 23. Tenth, one hundred and ten species of birds; flying creatures (vey = vâî) such as the griffon bird, the Karsipt, the eagle, the Kahrkâs which they call the vulture, the crow, the Ardâ, the crane, and the tenth is the bat. 24. There are two of them which have milk in the teat and suckle their young, the griffon bird and the bat which flies in the night; as they say that the bat is created of three races (sardak), the race (âyina) of the dog, the bird, and the musk animal; for it flies like a bird, has many teeth like a dog, and is dwelling in holes like a musk-rat. 25. These hundred and ten species of birds are distributed into eight groups (khadûînak), mostly as scattered about as when a man scatters seed, and drops the seed in his fingers to the ground, large, middling, and small. 26. Eleventh, fish were created of ten species; first, the fish Ariz, the Arzuvâ, the Arzukâ, the Marzukâ, and other Avesta names. 27. Afterwards, within each species, species within species are created, so the total is two hundred and eighty-two species. 28. Of the dog they say that out of the star station, that is, away from the direction of the constellation Haptôk-rîng, was given to him further by a stage (yôgist) than to men, on account of his protection of sheep, and as associating with sheep and men; for this the dog is purposely adapted, as three more kinds of advantage are given to him than to man, he has his own boots, his own clothing, and may wander about without self-exertion. 29. The twelfth is the sharp-toothed beast of which the leader of the flock is in such great fear, for that flock of sheep is very badly maintained which has no dog. 30. Aûharmazd said when the bird Vâresha was created by him, which is a bird of prey, thus: 'Thou art created by me, O bird Vâresha! so that my vexation may be greater than my satisfaction with thee, for thou doest the will of the evil spirit more than that of me; like the wicked man who did not become satiated with wealth, thou also dost not become satiated with the slaughter of birds; but if thou be not created by me, O bird Vâresha! thou wouldst be created by him, the evil spirit, as a kite with the body of a Varpa, by which no creature would be left alive.' 31. Many animals are created in all these species for this reason, that when one shall be perishing through the evil spirit, one shall remain.

(8) As for the genera (khadûînak), the first genus is that which has the foot cloven in two, and is suitable for grazing; of which a camel larger than a horse is small and new-born.

(1) And all dependent from Above are subdivided into species in the fashion which I am to tell. The genera of all things company with their own species; so that the genus is a class in its entirety, the species is part of a genus. The genus of the Gods will, therefore, make the species of the Gods out of itself. In like way, too, the genus of the daimons, and of men, likewise of birds, and of all [animals] the Cosmos doth contain within itself, brings into being species like itself. There is besides a genus other than the animal,—a genus, or indeed a soul, in that it’s not without sensation,—in consequence of which it both finds happiness in suitable conditions, and pines and spoils in adverse ones;—I mean [the class] of all things on the earth which owe their life to the sound state of roots and shoots, of which the various kinds are scattered through the length and breadth of Earth.

(10) Another method of division is possible: substances may be classed as hot-dry, dry-cold, cold-moist, or however we choose to make the coupling. We may then proceed to the combination and blending of these couples, either halting at that point and going no further than the compound, or else subdividing by habitation- on the earth, in the earth- or by form and by the differences exhibited by living beings, not qua living, but in their bodies viewed as instruments of life.

Differentiation by form or shape is no more out of place than a division based on qualities- heat, cold and the like. If it be objected that qualities go to make bodies what they are, then, we reply, so do blendings, colours, shapes. Since our discussion is concerned with Sensible Substance, it is not strange that it should turn upon distinctions related to sense-perception: this Substance is not Being pure and simple, but the Sensible Being which we call the Universe.

We have remarked that its apparent subsistence is in fact an assemblage of Sensibles, their existence guaranteed to us by sense-perception. But since their combination is unlimited, our division must be guided by the Form-Ideas of living beings, as for example the Form-Idea of Man implanted in Body; the particular Form acts as a qualification of Body, but there is nothing unreasonable in using qualities as a basis of division.

We may be told that we have distinguished between simple and composite bodies, even ranking them as opposites. But our distinction, we reply, was between material and organic bodies and raised no question of the composite. In fact, there exists no means of opposing the composite to the simple; it is necessary to determine the simples in the first stage of division, and then, combining them on the basis of a distinct underlying principle, to differentiate the composites in virtue of their places and shapes, distinguishing for example the heavenly from the earthly.

These observations will suffice for the Being , or rather the Becoming, which obtains in the Sensible realm.

(1) Now every single class of living thing, Asclepius, of whatsoever kind, or it be mortal or be rational, whether it be endowed with soul, or be without one, just as each has its class, so does each several [class] have images of its own class. And though each separate class of animal has in it every form of its own class, still in the selfsame [kind of] form the units differ from each other. And so although the class of men is of one kind, so that a man can be distinguished by his [general] look, still individual men within the sameness of their [common] form do differ from each other.

(3) The species, then, persists, as frequently producing from itself as many images, and as diverse, as there are moments in the Cosmic Revolution, —a Cosmos which doth [ever] change in revolution. But the idea [itself] is neither changed nor turned. So are the forms of every single genus permanent, [and yet] dissimilar in the same [general] form. XXXVI

(21) The claim of Motion to be established as a genus will depend upon three conditions: first, that it cannot rightly be referred to any other genus; second, that nothing higher than itself can be predicated of it in respect of its essence; third, that by assuming differences it will produce species. These conditions satisfied, we may consider the nature of the genus to which we shall refer it.

Clearly it cannot be identified with either the Substance or the Quality of the things which possess it. It cannot, further, be consigned to Action, for Passivity also comprises a variety of motions; nor again to Passivity itself, because many motions are actions: on the contrary, actions and passions are to be referred to Motion.

Furthermore, it cannot lay claim to the category of Relation on the mere ground that it has an attributive and not a self-centred existence: on this ground, Quality too would find itself in that same category; for Quality is an attribute and contained in an external: and the same is true of Quantity.

If we are agreed that Quality and Quantity, though attributive, are real entities, and on the basis of this reality distinguishable as Quality and Quantity respectively: then, on the same principle, since Motion, though an attribute has a reality prior to its attribution, it is incumbent upon us to discover the intrinsic nature of this reality. We must never be content to regard as a relative something which exists prior to its attribution, but only that which is engendered by Relation and has no existence apart from the relation to which it owes its name: the double, strictly so called, takes birth and actuality in juxtaposition with a yard's length, and by this very process of being juxtaposed with a correlative acquires the name and exhibits the fact of being double.

What, then, is that entity, called Motion, which, though attributive, has an independent reality, which makes its attribution possible- the entity corresponding to Quality, Quantity and Substance?

But first, perhaps, we should make sure that there is nothing prior to Motion and predicated of it as its genus.

Change may be suggested as a prior. But, in the first place, either it is identical with Motion, or else, if change be claimed as a genus, it will stand distinct from the genera so far considered: secondly, Motion will evidently take rank as a species and have some other species opposed to it- becoming, say- which will be regarded as a change but not as a motion.

What, then, is the ground for denying that becoming is a motion? The fact, perhaps, that what comes to be does not yet exist, whereas Motion has no dealings with the non-existent. But, on that ground, becoming will not be a change either. If however it be alleged that becoming is merely a type of alteration or growth since it takes place when things alter and grow, the antecedents of becoming are being confused with becoming itself. Yet becoming, entailing as it does these antecedents, must necessarily be a distinct species; for the event and process of becoming cannot be identified with merely passive alteration, like turning hot or white: it is possible for the antecedents to take place without becoming as such being accomplished, except in so far as the actual alteration has "come to be"; where, however, an animal or a vegetal life is concerned, becoming takes place only upon its acquisition of a Form.

The contrary might be maintained: that change is more plausibly ranked as a species than is Motion, because change signifies merely the substitution of one thing for another, whereas Motion involves also the removal of a thing from the place to which it belongs, as is shown by locomotion. Even rejecting this distinction, we must accept as types of Motion knowledge and musical performance- in short, changes of condition: thus, alteration will come to be regarded as a species of Motion- namely, motion displacing.

(2) But are we really obliged to posit the existence of such genera?

Take Substance, for Substance must certainly be our starting-point: what are the grounds for regarding Substance as one single genus?

It has been remarked that Substance cannot be a single entity common to both the Intellectual and the Sensible worlds. We may add that such community would entail the existence of something prior to Intellectual and Sensible Substances alike, something distinct from both as predicated of both; and this prior would be neither body nor unembodied; for it were one or the other, body would be unembodied, or the unembodied would be the body.

This conclusion must not however prevent our seeking in the actual substance of the Sensible world an element held in common by Matter, by Form and by their Composite, all of which are designated as substances, though it is not maintained that they are Substance in an equal degree; Form is usually held to be Substance in a higher degree than Matter, and rightly so, in spite of those who would have Matter to be the more truly real.

There is further the distinction drawn between what are known as First and Second Substances. But what is their common basis, seeing that the First are the source from which the Second derive their right to be called substances?

But, in sum, it is impossible to define Substance: determine its property, and still you have not attained to its essence. Even the definition, "That which, numerically one and the same, is receptive of contraries," will hardly be applicable to all substances alike.

(25) There are those who lay down four categories and make a fourfold division into Substrates, Qualities, States, and Relative States, and find in these a common Something, and so include everything in one genus.

Against this theory there is much to be urged, but particularly against this posing of a common Something and a single all-embracing genus. This Something, it may be submitted, is unintelligible to themselves, is indefinable, and does not account either for bodies or for the bodiless. Moreover, no room is left for a differentia by which this Something may be distinguished. Besides, this common Something is either existent or non-existent: if existent, it must be one or other of its species;- if non-existent, the existent is classed under the non-existent. But the objections are countless; we must leave them for the present and consider the several heads of the division.

To the first genus are assigned Substrates, including Matter, to which is given a priority over the others; so that what is ranked as the first principle comes under the same head with things which must be posterior to it since it is their principle.

First, then: the prior is made homogeneous with the subsequent. Now this is impossible: in this relation the subsequent owes its existence to the prior, whereas among things belonging to one same genus each must have, essentially, the equality implied by the genus; for the very meaning of genus is to be predicated of the species in respect of their essential character. And that Matter is the basic source of all the rest of things, this school, we may suppose, would hardly deny.

Secondly: since they treat the Substrate as one thing, they do not enumerate the Existents; they look instead for principles of the Existents. There is however a difference between speaking of the actual Existents and of their principles.

If Matter is taken to be the only Existent, and all other things as modifications of Matter, it is not legitimate to set up a single genus to embrace both the Existent and the other things; consistency requires that Being be distinguished from its modifications and that these modifications be duly classified.

Even the distinction which this theory makes between Substrates and the rest of things is questionable. The Substrate is one thing and admits of no differentia- except perhaps in so far as it is split up like one mass into its various parts; and yet not even so, since the notion of Being implies continuity: it would be better, therefore, to speak of the Substrate, in the singular.

(10) The third genus is that of the five-dividing paw, of which the dog is the largest, and the civet-cat the least.

(3) But perhaps we should rather speak of some single category, embracing Intellectual Substance, Matter, Form, and the Composite of Matter and Form. One might refer to the family of the Heraclids as a unity in the sense, not of a common element in all its members, but of a common origin: similarly, Intellectual Substance would be Substance in the first degree, the others being substances by derivation and in a lower degree.

But what is the objection to including everything in a single category, all else of which existence is predicated being derived from that one thing, Existence or Substance? Because, granted that things be no more than modifications of Substance, there is a distinct grading of substances themselves. Moreover, the single category does not put us in a position to build on Substance, or to grasp it in its very truth as the plausible source of the other substances.

Supposing we grant that all things known as substances are homogeneous as possessing something denied to the other genera, what precisely is this something, this individuality, this subject which is never a predicate, this thing not present in any thing as in a subject, this thing which does not owe its essential character to any other thing, as a quality takes character from a body and a quantity from a substance, as time is related to motion and motion to the moved?

The Second Substance is, it is true, a predicate. But predication in this case signifies a different relation from that just considered; it reveals the genus inherent in the subject and the subject's essential character, whereas whiteness is predicated of a thing in the sense of being present in the thing.

The properties adduced may indeed be allowed to distinguish Substance from the other Existents. They afford a means of grouping substances together and calling them by a common name. They do not however establish the unity of a genus, and they do not bring to light the concept and the nature of Substance.

These considerations are sufficient for our purpose: let us now proceed to investigate the nature of Quantity.

(1) We have examined the proposed "ten genera": we have discussed also the theory which gathers the total of things into one genus and to this subordinates what may be thought of as its four species. The next step is, naturally, to expound our own views and to try to show the agreement of our conclusions with those of Plato.

Now if we were obliged to consider Being as a unity, the following questions would be unnecessary:

Is there one genus embracing everything, or are there genera which cannot be subsumed under such a unity? Are there first-principles? Are first-principles to be identified with genera, or genera with first-principles? Or is it perhaps rather the case that while not all genera are first-principles, all first-principles are at the same time genera? Or is the converse true? Or again, do both classes overlap, some principles being also genera, and some genera also principles? And do both the sets of categories we have been examining imply that only some principles are genera and some genera principles? or does one of them presuppose that all that belongs to the class of genera belongs also to the class of principles?

Since, however, we affirm that Being is not a unity- the reason for this affirmation is stated by Plato and others- these questions become imperative, once we are satisfied as to the number of genera to be posited and the grounds for our choice.

The subject of our enquiry, then, is the Existent or Existents, and it presents immediately two problems demanding separate analysis:

What do we mean by the Existent? This is naturally the first question to be examined.

What is that which, often taken for Being , is in our view Becoming and never really Being? Note however that these concepts are not to be taken as distinguished from each other in the sense of belonging to a genus, Something, divided into Being and Becoming; and we must not suppose that Plato took this view. It would be absurd to assign Being to the same genus as non-Being: this would be to make one genus of Socrates and his portrait. The division here means a definite marking-off, a setting asunder, leading to the assertion that what takes the appearance of Being is not Being and implying that the nature of True Being has been quite misapprehended. Being, we are taught, must have the attribute of eternity, must be so constituted as never to belie its own nature.

This, then, is the Being of which we shall treat, and in our investigation we shall assume that it is not a unity: subsequently we ask leave to say something on the nature of Becoming and on what it is that comes to be, that is, on the nature of the world of Sense.

(1) And yet the species of all genera are interblended with all genera; some which have previously been made, some which are made from these. The latter, then, which are being made,—either by Gods, or daimons, or by men,—are species all most closely like to their own several genera. For that it is impossible that bodies should be formed without the will of God; or species be configured without the help of daimons; or animals be taught and trained without the help of men.