36—» 7. Aristotle has shown that a species is unified by the fact that its genus exists only as the matter of its differentia, and its differentia only as the form of its genus. This explanation does not apply to swmma genera (i.e. categories), which have no matter either intelligible or sensible. The unity of these, however, needs no explana- tion; they are by their own nature instances of unity (dep & 71), as they are instances of being. Because unity and being are inevitably predicable of them, unity and being are not mentioned in their definitions (really, of course, they have no definitions but can merely be described, Alexander 563. 17).
The section contains a certain amount of repetition, but this is for the sake of emphasis. The rearrangements of the text by Alexander and Schwegler are not necessary and do not help matters ; the justifica- tion of 86 in 2, which was the point that troubled them, lies in ei@us (* 36). Since any swmmum genus must from its very nature be a one and an existent, ‘one’ and ‘existent’ need not be inserted in the definition of any swmmum genus.
b 6-7. odx 4s... mapa ta KaO” Exacta is evidently directed against the Platonists,
6. otx ds... vi. Aristotle holds that being and unity are not genera, for reasons given in B. 998 22 ff. Each of them is one 7 ad’ évos OF T@ Tpos ey OF Kar’ avadoyiar.
7. 088 &s xwpiotay dvtwr, sc. rod dvros Kal Tod évds. TH Kal Exacta = the several categories.
8. ot pév, Plato and his followers, A. 987” 13.
10. Wux‘s is evidently an emblema from the next line.
Avuxédpov, an orator and sophist of the school of Gorgias, mentioned several times by Aristotle (Zop. 174” 32, Phys. 185 28, Pol. 1280? 10, Rhet. 1405» 35, 14067 7, 1410717). Cf. Zeller io 1323, n. 3.
12-16. Evidently Aristotle means to refute these explanations by a reductio ad absurdum. The absurdity lies in the application of terms like o¥vGects to things that never existed apart.
15. 76 Neukdv etvar. Bz.’s ro ryv émupdveravy Aevkov etvar would be easier, but the subject of Aevxdy efvar may as well be omitted as that of byaivew (1. 13). A surface is the only thing that can fer se be white.
18. domep eipytar. Aristotle has not actually said this; he is refer- ring loosely to 4 23-33.
But the ellipse would be unusually harsh here, and Casaubon may be right in inserting 76 ev. In any case, it seems best to read €y with ACs
@ote Suovoy KT. ‘ So that it is like asking what in general is the cause of unity and of a thing’s being one’—which is an obviously absurd question.
Book ©
Potency (chs. 1-5).
Potency in the strict sense, t.e. power to produce motion (ch. 1).
1045 27. We have treated of primary being, to which all the other categories imply a reference, viz. substance; since being is divided according as it means potency or complete reality as well as according to the categories, we must discuss potency and complete reality.
35. First we will discuss potency in the strict sense, which, however, is not the most suitable to our present purpose. Later, in our dis- cussion of actuality, we will explain the other senses of potency.
240 Commentary
104624. We may set aside the potencies that are so called by equivocation (i.e. potencies or powers in geometry).
g. Potencies in the proper sense are originative sources, and are called potencies by reference to a primary kind (a), that which is a source of change in another thing or“in the thing itself gwa other. The derivative kinds are (2) the potency of being acted on, of being changed by another or by the thing itself gva other, and (c) insuscepti- bility to change for the worse by the agency of another thing or of the thing itself gua other,
16. Again, these are potencies of acting or being acted on simply, or of acting or being acted on well; the definition of the former is implied in that of the latter.
1g. In a sense the potency of acting is one with that of being acted on; in a sense it is different. ‘The one is in the patient (it is because even the matter is a motive principle that things can be acted on, different things by different things); the other is in the agent. Thus so far as a thing is an organic unity it cannot be acted on by itself, for it contains no distinction of agent and patient.
29. To every potency there answers a privation of potency, an incapacity to do that same thing in that same relation. We say a thing is ‘deprived’ of an attribute (1) when it has not it, (2) when it might naturally have it but has not it—has not it (a) at any time or (6) when it might have it, and again (a) has not it in a particular way (e. g. completely) or (8) has not it at all. Again, we sometimes mean that it is prevented by force from having what it would naturally have.
1045 28. eipytar. The reference is to ZH in general.
32. elmopev év Tots mpwTois Aéyots. The point has been made both in T. 1003 33 andin Z. x. As it is doubtful whether I was originally part of the same treatise as @, Z seems likely to be meant here.
32-34. émel 8¢...épyov. For the full list of meanings of év cf, E. 10264 33- 2,
85—1046? 4. The two senses of dvvayus which Aristotle wants to distinguish may be indicated by the words ‘ power’ and ‘ potentiality’ respectively. He proposes to treat first of power, and then, in discuss- ing actuality, to treat incidentally of potentiality (1046% 2-4). Power he explains as primarily a power in A to produce a change in B, or in A, considered in one respect, to produce change in itself in another respect (104611). Potentiality on the other hand is a potentiality in A of passing into some new state or engaging in some new activity (1048 32). This activity may be the production of a change in B, but the notion of a B to be acted on is not necessarily implied in the
notion of potentiality, as it is in that of power. The notion of power is obscure enough, but it is certainly familiar and it is easily distin- guished from that of potentiality. But Aristotle proceeds to treat as subsidiary to the notion of power as distinct from potentiality, of h kata Kivnow divas (1046* 2), (2) the power in A of being changed by B and (4) the power in A of not being changed for the worse by B (t1-15). In these ‘powers’ part of the distinctive nature of power as against potentiality is still present—viz. the distinct implication of two things A and B; but the other part of its distinctive nature is gone—viz. the implication of positive force, for in (a) weakness rather than force, and in (6) inertial resistance rather than force is implied as being present in A. That Aristotle does not successfully preserve the distinction between power and potentiality is further indicated by the facts noticed by Bz., that in the discussion of power he introduces (1) a definition of dvvardv which clearly refers to potentiality rather than to power (1047 24), and (2) a lengthy section which also refers to potentiality rather than to power (1047 3-30).
10464 2, eimdvtes epi tavTys, in chs. 1-5.
3. ev Tois mepl Tis evepyelas Sioptopois, chs. 6-10. The precise reference is to 1048 27.
5. év GXous, A. 12.
7. xaddaep év yewpetpia. Cf. A. 1019) 33 n.
8. Schwegler puts a comma after yewmerpia and takes kal dvvard xr. as referring to the senses of dvvarov and advvaroy expounded in A. 1019 21-33, but the run of the sentence forbids this.
13. dmaletas Tis emt 16 xetpov is used elliptically for dmaeias pera- BodHs THs ext 76 xepov, and dOopas depends, like the ‘ understood’ peraBoArys, ON dmrabeias.
17. tod before zafety seems pretty certainly to have been inserted by a copyist who did not see the point.
19-20. éort pev... mdoyew. In saying that the power of acting and that of being acted on are in a sense one Aristotle does not, as Bz. supposes, make use of an ambiguity in the phrase apy) peraBodArs év dAXw (1.11), by which év d\Aw can be taken either with apy or with peraBoAjs. The whole context shows that év d\Aw goes only with peraBodys; it is in virtue of this that dpyy peraBodjs ev dAAw can be opposed to dpyy peraBodrns jm’ GAdrov (I. 12). Rather the unity, in some sense, of the active and the passive dvvayis is based on this, that the single fact that A can change B leads us to ascribe both an active power to A and a passive power to B. The active and the passive power are thus the complementary aspects of a single fact. Cf. De An. 425» 25—426* 30,
24. 76 AuTapdv pev yap Kkavotév. I.e. that which suffers burning must have a matter which lends itself to burning ; it must be fat.
28. cupmépuxer, cf. Z. 1040 15 n.
BI. 7 3é orépyors Aéyetar ToAAaxds, cf. A. 22.
242 Commentary
Rational and non-rational potencies (ch. 2).
1046? 36. Some potencies are irrational, others rational ; thus the arts are potencies. :
b 4. Rational potencies are of contraties, irrational of one result only; the hot can only heat, but the medical art can cause either disease or health, because knowledge is a rational account and the same account explains both a thing and its privation ;
g. but it explains the one essentially, the other incidentally by the absence of the first.
15. Thus the scientific man, starting from the single principle of movement which he has in his soul, can produce contrary results, linking both movements syllogistically with the same rational account.
24. The power of doing a thing well (or being acted on well) implies the power of doing it (or being acted on), but not vice versa.
1046) 3. at wowntiKal émorhpat = ai téxvau. xaé is explicative. Cf, A. 1075° 1.
4. at wey peta Adyou aca toy évavtiwv at adtat. Aristotle is not asserting contingency in the sphere of rational powers—asserting that precisely the same cause can produce opposite results. Opposite results may supervene on the presence of a single Adyos, but it has not been their sole cause; didvova, adr ober xwel (L. V. 1139 35); desire or choice turns the scale (1048*10). The Adyos has been accom- panied in the one case by the desire, say, to cure, in the other by the desire to kill, and this accounts for the difference in the result.
14. yap ortépnors | mpwTy 7d evavtiovy, eévaytiwors proper is erépyous teheia (I. 1055% 34); if a subject which might have a certain attri- bute completely fails to have it, this state is ‘contrary’ to the state of having the attribute completely.
15. éwet Sé ta evavtia ok éyylyverar év TG atte. This gives the reason for 76 pév byvewov. . . Wuxpdéryta, while 4 8 emurrnun . . . dpxnv gives the reason for 6 8 émorjpwov audw; and it is on 6 & émorjpov apdw and the reason for it that the stress falls. ‘ While the wholesome produces only health because its power gua wholesome, being an irrational power, is a power only to produce health and the law of con- tradiction forbids its having also the contrary power, on the other hand since knowledge . . ., the man who has knowledge can produce both,’
20. Adyos yép... pév. ‘For it (the Adyos mentioned in 1. 17) is a Adyos of both the contrary results.’
21. H xe. Jaeger prefers 7 éyer, but Alexander read # éyet (570. 6). The Adyos is not present in a Soul in virtue of the soul’s having an dpx7 of movement, but is present in a soul which in fact has such an apxy, and it is this coincidence that leads to action.
21-22, Alexander explains both tis atris apxis and taité as 76
Aoyorixov. That ris abrys dpyjs means 6 Adyos is shown by |, 24, and tavré probably means this also, The soul will initiate either of two contrary movements as a result of the same originative source, the account it has framed for itself of the object, and it will have linked both movements with the same thing, i.e. deduced them from this account as the movements necessary to bring the object into existence or to prevent its coming into existence. For cvvdrrew used of syllogistic ‘linking up’ cf. Az. Pr. 4121, 12, 19, 65> 33, 692 18, 19.