Since, however, every entity is expressed ac- cording to some one thing, and something that toiogkal °^ °^ is common, which is multifariously predicated,^ ^^rt^i** '®*** and as contraries are expressed in the same manner — for they are referred to the primary contrarieties, and differential qualities of entity — and since it is possible that things of this kind should fall under the notice of one science, hence the doubt expressed in the opening parts of this work respecting first principles would be dissolved in this way. Now, the doubt I allude to is that wherein the matter of perplexity i& involved in the question as to how there will be one science about entities that are many in number, and which are generically different?
CHAPTER IV.
But since, also, the mathematician employs 1. how far things that are common in a manner peculiar to mathematics himself, it would be the province of the First parts of meu^ Philosophy, that is, of Ontology, to speculate into P^y"^'*- the original principles of these things. For that when from 1 This is precisely the mode of reasoning pursued by Arietotid in 9odk IIL ch»p. ii, already referred to.
888 THB HBTAPHTSIOS OF ABIBTOTIiB. [BOOK & equals equals are taken away the remaindere are equal ifly indeed, a dogma that is common to all quantitiea Matne* matical science, however, speculates about a certain portion of matter, properly so called, appropriating it to itself; aa, fot instance, about lines, or angles, or numbers, or something else pertaining to other quantities: not, however, as &tr forth as they are entities, but so far forth as each of them is that which is continuous in one, or two, or three dimensions. Philosophy, however, does not institute an inquiry respecting those i)articulars that are contained in a certain portion of matter, as far forth as something amongst them is an accident in each of these, but it contemplates everything of this kind respecting entity, so far forth as it is entity. And in the same manner, also, does the case stand in regard of physical science as with mathematical; for physical or natural science speculates into the acciderts or first principles of entities, so hx forth as they are in motion, and not so fax forth as they are entities. But we have said that Ontology, or the First Science, is conversant about these in as far as the subjects of them are entities, but not so &r forth as they are anything that is different. Wherefore, we may set down that both this and the science of the mathematician are parts of Wisdom or Metaphysical Science.
CHAPTER V.
1. Certain uiti- Therb is involved, however,^ in entities a cer- Se^at the"bad" ^^^ ^^^ principle about which it is not possible of all demon- to labour under any deception, but it is necessary itration. invariably to do the contrary; now, I mean to speak conformably with truth: as, for instance, that it is not admissible that the same thing should be and not be in one and the same period of time; and the case is so with other things that are opposed to themselves in the same manner. And, respecting points of this kind, demonstration, indeed, has no existence absolutely speaking; but in respect of this principle it ha^ (for it is not possible to construct a process of 1 Vide book UL chap. liL OR.T.] TH09E WHO DBNT FUNDAlOBHTAfi AXIOMS. 289 syllogistio reasoning from a more trustworthy principle than this very axiom just mentioned,) and it ougtit to be so, at any rate, if it is possible that there should subsist such a thing as a demonstration in absolute terms.
As regards a person, however, who makes an j. Refutation assertion of opposite statements,^ for the purpose of those who of proving wherefore it is false, must some such such fundL position be assumed, as that although the thing "nentai axioms, will actually be the same with the non-possibility of being the same tiling, and not being so at one and the same time, yet that it will not appear to be the same thing with it; for after this manner only can a demonstration be brought about in regard of one who affirms the admissibility of opposite assertions being verified of the same thing. And, ^^ ^^^ ^ in the next place, those people who are likely to ture of phiio- take their share in mutual discussion ought, in JJp^*';^ ^**'^"'- some degree, to understand themselves; for, in case this be not done, how will there subsist with these persons a community in regard of such mutual discussion? It is neces- sary, then, that each of the denominations should be known, and that they manifest some one thing, and not many things, but only one; and if it is equivalent in its significa- tion to many things, one ought to make it evident towards which of these significations the denomination conducts one. Now, as regards a person who affirms that this thing both is and is not, this which he in general affirms to be, he affirms not to be: wherefore, he asserts that the name signifies that which it does not signify; but this is impos- sible. Wherefore, if the assertion that the being of this particular thing involves any signification, it is impossible that contradiction concerning the same thing should be veri- fied. Further, if a name has any meaning, and this be capable of verification, this also must needs be from necessity; but that which is from necessity it is not admissible at any time' should not be: it is not for this reason^ then, admissible that opposite assertions be true concerning the same thing.
^ This book contains a somewhat more elaborate refutation of Scep- ticism than book III. Vide note, p. 277.
' This principle has been brought forward by Dr. Clarke in hit unsuccessful attempt at an d priori demonstration of the existence of God. Some copies read r6r€ instead of itc^tc* 12 290 THE MRTAPHTfifOS OF ARISTOTLE. [BOOK X and of affirma- Further, on the supposition that assertion in no tion compared degree is moFO true than negation, the person ^ ' who makes the affirmation that one is a man will in nowise the rather make a true statement than if ha were to affirm that he is not a man: and a person who affirms a man not to be a horse would appear to speak truth either in a greater or not in a less degree than if he affirms that man is not man. Wherefore, one who affirms, also, that the same is a horse will speak true; for, in a similar way, it would be possible that opposite assertions should admit of verification. Wherefore, the consequence ensues that the same creature should be man and horse, or something else belonging to the animal kingdom. There does not, therefore, subsist in regai'd of these any demonstration in absolute terms: as relates, however, to the person who is for establishing these foregoing points, demonstration has an existence. 3. Aristotle And quickly would one, likewise, who after thus exposes ^jjig manner had put the question to Heraclitus ^ tne erroneous tne erroneous system of the himsclf, forco him to acknowledge that it is never Heraciitics. ^ thing that is possible that opposite assertions should be verified of the same things; but at present, not com- prehending his own theory in regard of what he says at all, he has embraced this particular opinion we have been just endeavouring to overthrow. And in general, if the statement made by Heraclitus be true, neither would this very position of his be true; now, I mean the admissibility that at one and the same time the same thing should be and not be. For as also, on the supposition of these assertions having been divided, in no respect the more will affirmation be true than negation, in the same manner, likewise, will it be the case when both are conjoined and connected together — just as if affirmation is regarded as being one certain thing, in no degree the more will negation be true than the entire of the assumption which is made in an affirmation. Moreover, if it is possible to ^ake no affirmation that is true, even would this very position be false — I mean, the assertion that no affirmation is true: if, however, there exists any assertion that is true, that point which is put forward by these Hera- viitics would be decided — I mean, such philosophers as resist ^ Heraclitus and Protagoras are the sceptics whom Aristotle chieflj directs his attack againat.
€H. VI.J ' MAN VIEWED AS A MEASURE OF THINGS. 291 the truth of things of this sort, and, in fact, altogether do away with rational discussion.
CHAPTER VI.
But similar to the statements * that have been i. The Prou- just made is that which has been asserted by gorean dogma Protagoras j for, likewise, he said that man is the measure of a measure of all things, — in this way affirming ^^ things. nothing else than that what appeared to every man, that this, also, indubitably is that which it appeared to be: if, how- ever, this is admitted, the same thing will happen to be and not be, and to be both evil and good, and the rest of those things that are expressed in accordance with opposite asser- tions, from the feet that frequently to some pei-sons, indeed, this pai-ticular thing appears to be fair, and the contrary to others, and from that which is apparent to every one consti- tuting a measure.
Now, this doubt would be resolved if persons ^ ^^. ^^ considered whence the origin of this supposition of this dogma has been derived; for to some speculators, no iiJn-wheJhM doubt, it would appear to have originated from itbefromnatu- the opinion of the Physiologists, or Natural Phi- ' ^ ^ °*°^ ^' losophers, but to others from the circumstance that all men do not possess the same points of knowledge in respect of the same subjects, but that to some this particular thing seems to be sweet, and to others the contrary. For that nothing is generated from nonentity, but everything from entity, is almost a commonly received dogma amongst all Natural Philosophers. Since, therefore, that which is not white is generated from that which is perfectly white, and by no means not white, supposing, now, that what is not white has been generated from that which is not a white entity, that which is being generated as not white would be produced.
^ This error of Protagoras is an inveterate failing in human philo* wophj. It is noticed by Bacon in terms of strong reprehension. Itf e£»cts en theology might be illustrated in the rise of Anthropo- morphism. Vide Hagenbach's History of Doctrines, vol. I. pp. 103 — 107: translated in Clark's "Foreign ITieological Library;" Cud worthy rcl. I p. 201; Bacon, De Augm. lib. V. cap. iv.
292 THE HBTAFHYaiOB OF ARISTOTLE. [BOOK X Wherefore, such would be generated from nonentity, accord- ing to their doctrine, unless that which is not white were the same with that which is white. It would not, however^ be difficult to decide this doubt; for it has been declared, in our treatise on Physics, in what manner from that which is non- entity are generated the things that are being produced, and how it is that they are generated from entity. Notwith- standing the giving heed, in like manner, to both opinions, and to the fanciful statements of persons who doubt iu opposition to themselves, this would be a silly proceeding; for it is evident that one party amongst these sceptics must needs labour under &Ilacies. And this statement serving the is manifest from observing things that are gene- senseT*"* ®^ rated according to sense; for at no time does the same thing appear to some, indeed, sweet, and to others the contrary, provided that the organ which has the power of perceiving and deciding the above-enumerated tastes has not undergone any corruption and injury in the case of these others. But, on the understanding of such a state of things as this, we may suppose that some of them are a stand- ard of measure, and suppose that others are not so. And, in like manner, I assert this to be the case as regards both what is good and evil, and what is beautiful and disgraceful, and • other things of the sort; for to lay down this as a principle, or to affirm the reality of nothing save the apparent, is a course nowise diflTerent from those who place their finger beneath the organ of vision, and thus from the one object make two to appear, and who really believe that there are two objects before them, on account of their appearing such, '^ and again that there is but one in reality; for to those per- sons who do not move their organ of vision that which is one appears one.
s Thedffic ^^ general,^ however, it v juld be absurd, from of attaining the appearance of things cnat are here as subject this°matter!" *^ change, and which never permanently con- tinue in the same dispositions, from this to oome to any decision as regards truth; for it is necessary that we should go in pursuit of that which is true from amongst those things that invariably do subsist according to the same ' Seztus Empiricus has laid hold on a priaciple such as this to establish his philosophic srstem.
CH. VI.] REFUTATION OF THIS NOTION. 293 dispositions, and that never are instrumental in bringing about their own change. Now, of this description are those bodies that are regulated acoording to the orderly system of the Universe; for these do not at one time appear of this particular sort, but at another time of a different kind, but invariably the same, and as participating in no change.
But, further, on the supposition of the exist- 4 j^^^ ^jjcctt ence of motion, and of something that is being refuted trom moved, — now, everythmg which has motion im- of flux and pressed upon it is put in motion by something, motion. and in the direction of something, — in such a case, that which is being moved ought to be found, moreover, in that from which it will derive its motion, and yet not be found therein, and that it should be moved towards this particular place, and yet should not be generated in this: but how can such be the case 1 for we must bear in mind, that, even according to their own doctrines, that simultaneous verification^ is not possible as regards contradiction. And if, according to quan- tity, things which are here are continuously in a state of flux, and are being moved, — and if one admits this, although it should not be true, — why are they not permanent as regards quality 1 for these speculators in no small degree appear to predicate those things of the same thing, according to their contradictions, from the supposition that quantity does not continue permanently in bodies. Hence with them the same thing is and is not of four cubits in its dimensions. Sub- stance, however, subsists according to quality, for this is of a definite nature; but quantity belongs to one. which is indefinite.
Further, why, let me ask, when the physician ^. p...gives a prescription that his patients should take argument this particular food, — why, I say, do they take g^raS.*'^"** it^ for why is this particular piece of food bread rather than it is not bread? Wherefore, there would be no distinction in eating from not eating. At present, however, as the physician makes a true assertion about this thing, and this food that has been prescribed being in reality in existence, the patient* accordingly take this food — although they ought not, at least, to do so on the supposition that ^ The word thus rendered is (rvpa\ri0§6t(r0au, ' Vide hook IIL chaps, iv. t. and vi 294 THE MEXAFHTSCS OF ABSSn/rVK, IBOOKX, there is no nature that is firmly permanent in sensibles, l,i4 that icTariably all things are in motion and in a state d $. Argameut Anx. But farther, i^ indeed, we are always J'**"* *»^ undergoing a diange,* and never remaining per- jectirky of oar maneutly the same persons, why is it surprising •ensatumt. j^£ things never appear at any time to be the same as they do to those that are sick f For to these, aiso, on account of their habit being not similarly disposed as when they are in a healthy state, the things that subsist according to the senses do not appear to subsist in a similar manner; though sensibles themselves participate in no change on account of this, at least, but produce different sensations in the sick, and sensations that are not the same. In the same manner, therefore, is it requisite, perhaps, that consequences be disposed as if the aforesaid change took place. If, however, we do not undergo a change, but continue to be the same, there would be something in existence that is permanent.
Respecting, to be sure, those persons, therefore, McepticM eaiier who entertain from principles of reason the anothCT.'***" doubts enumerated, it would not be easy to advance a refutation when they are not for admitting anything, and no longer demand a reason of those things, for all reasoning, and every demonstration, aiise in this way; for when they are disposed to admit nothing, they overturn the thing in dispute, and, in general, all rational discussion. Wherefore, with such speculators, of course, there is no such thing at all as rational discussion; but in regard of those tha,t labour under perplexity, from the doubts that have been handed down, it would be easy to reply, and to unravel the difficulties that create in them the doubt referred to; now this statement is evident from those that have been made Wherefore, it is evident from these things that fhercforit'con- i^ ^^cs not admit of being possible that opposite trndiction, nor assertions about the same thing should be veri- mcdla.'^cnn be*'^ ficd at ouc and the same time, nor that con- w^Ii"tho*»ame ' ^^aries should, on account of the denomination of ihini? a: the all contrariety according to privation. This, how- •amotone. qyqj^^ will be evident to those who resolve into 1 Thus AriRtotlo turns the veapons of attack employed by Prot» gf.tm« to inflict wounds on the sceptic himself.
OH. VII.] ONTOLOGY A DISTINCT SOIENOB. 295 their first principles the definitions of contraries. And, in.ke manner, neither is it possible that any of those things that are media should be predicated of one and the same thing; for, on the supposition of the subject being white, when wo assert that this is neither white nor black we shall make a false assertion, for it happens that this is white, and yet that it is not; for either of these connected together will be verified concerning this, but this amounts to a contradiction of what is white.
Neither, therefore, is it possible for one who makes an assertion, in accordance with the theory ^ij^e the error of Heraclitus, nor of Anaxagoras, to assert what Jie* "> ^^e is true; and if this be not admitted, the conse- Anaxa^onu quence will ensue that they predicate contrary SJtiM*^*^ things of the same subject: for when Anaxagoras says that in everything is contained a part of everything, he says that a thing is not more sweet than bitter, or anything else of the other contrarieties, if in everything all things subsist not merely in potentiality, but in energy or activity, and in a state of separation. And, in like manner, neither is it possible that all assertions be false, nor all true,^ as well on account of many other difficulties which would be uttered in consequence of this position, as also because as regards all assertions, supposing that they are false, neither will one who makes this very assertion speak what is true; but if all assertions are true, the person who says that all are false will not speak &lsely.
CHAPTER VII. But every science investigates into certain first, ^ prmciples and causes respecting each of those province of objects of knowledge that fall under its cogni- JcJnceg"n sance; as, for example, medicinal science, and that contrast with of the athlete, and each of the rest of the pro- phy^gfcsr*^" ductive or the mathematical sciences; for each of these having been for itself descriptive of a certain genus, ^ A reference to book IIL will show that thevariotiB sceptical systemi may be reduced to two, where assertions to this effect are put forward Vide book III. ohap. yiiL 21^6 THB 1CBTAPHTBI08 OF ABIBTOTLB. [BOOK X treats canc6ming thits as a thing existing and asaii eiitity, not, nowever, so far forth as it is an entity: oomersant, however, about this last-named inquiry is there beside these sciences this certain other science of the Ontologist, which is different from them; but each of the aboTe-enumerated sciences, taking for granted the mode in which the nature of a thing subsists in each genus, endeavours to explain the remainder of the points relating to this more feebly or mere accurately. They, however, make an assumption as to quiddity, or the nature of a thing, some of them by means of sense, but others from hypothesis. Wherefore, it is also evident, from an in- duction of this sort, that there subsists no demonstration of substance and quiddity.
Since, however, there exists a certain science ^ ph«o8°fphJ^ which is conversant about Nature, it is manifest » distinct that it will be different from both that which is thed!^tinc^es8 practical scieuce and that which is productive or of its subject- effective. For of productive science the first inaynotthisbe principle of motiou resides in the producing oi ontology ToS efficient cause, and not in that which is being pro- duced; and this either is some art, or some other potentiality. And, in like manner, does the case stand with practical science also; the motion does not reside in the thing done, but rather in those who are agents. But the science of the Natural Philosopher is conversant about those bodies that involve in themselves a first principle of motion. That, indeed, therefore, Physical Science must needs be neither practical nor productive, but speculative or contemplative, is evident from these statements; for there is the necessity of its falling under the classification of some one of these genera. And since, in a manner, it is requsite for each of the sciences to possess a knowledge of the nature of a thing, and to employ this as a first principle, we ought not to forget how a definition of this quiddity should be framed by the phy- sical inquirer, and how th* definition of substance is to be assumed, whether as the iiat-nose, or rather as the hollow; for, as regards these, the formal principle, no doubt, of fiat-nose is denominated along with matter — I mean, such as belongs to the thing itself; the formal principle, however, of hollow nose is expressed without matter, for flatness of nose ii ^ Vide book Y. chape, i and ii OIL VIL] the YfiRT NATURE OF OXTOLOGY PROVES THIS. 297 generated in the nose. Wherefore, also, the definition or formal principle of it is inquired into along with this, for the Hat- nose constitutes a hollow-nose. It is evident, therefore, that the definition hoth of flesh, and of the eye, and of the other parts of the hody, is always to be assumed along with matter.
But since there exists a certain science of ^ ^^^^^ ^^ j^. entity,^ so far foith as it is entity, and so &r ontology, m » forth as it involves a separable subsistence, we Siltfngiul*, must examine whether at all we are to con- it from phyrica, eider this to be the same with Natural or Phy- °'™*' ematics. sical Science, or rather to be different from it. Physical Science, indeed, then, is conversant about those bodies that involve in themselves a first principle of motion; but the science of the mathematician is itself a certain science that is speculative, I admit, and that, too, in regard of things that are permanent, but which do not involve a subsistence separable from sensibles. Eespecting, then, that which is an entity capable of separate subsistence, and which is immovable, there exists a certain science different from both of these, on the supposition, of course, that there is some substance of this description in existence — now, I speak of a substance separ- able and immovable; and it is the validity of this very position that we shall attempt to demonstrate.
And if we admit that there subsists any sub- 4^ out of the stance of this sort in entities, here also, in a three speculamanner, would there be found Divmity residmg, theology the and this would be an original and most dominant "^'*'" dignified, principle. It is evident, therefore, that there are three genera of the speculative sciences — namely, the physical or natural, the mathematical, and the theological. The most excellent, then, is certainly the genus of the speculative or contempla- tive sciences; and of these very sciences that one which ia mentioned last of the three possesses ^ the greatest amount of excellence, for it is convei*sant about that one amongst entities which is more entitled to respect than the rest Each Bcience, however, is termed more excellent, and more inferior, according to its appropriate object of scientific knowledge.
1 Compare what is said iu chap. IV. of this book. ' This point has been established by Aristotle iu the opening chapton of the Metaphysics. Vide p. 10.
298 THE 1IETAPHT8ICS OF ARISTOTIJB. {BOOK X, Now, a person might raise the question as t-s the validity of whether at all we ought to seek to establish uni« metophysicai versally the science of entity, so far forth as it is entity, or not 1 For each of the mathematical sci- ences, no doubt, is conversant about some one definite genus; the universal science, however, speculates in common respect- ing all things. I? indeed, therefore, we admit physical substances to be the primary substances of entities. Physical or Natural Science would also be the chief one amongst the sciences; but, on the other hand, if there exists a nature that is different, and a substance that involves a separable subsist- ence, and is immovable, it is necessary, also, that there belong to this a different science, and that this science should be ant-ecedent to physical science, and universal in respect of its antecedence or priority.
CHAPTER VIII.
1. NoBcienceof SiNCE, howevcr, that which is entity simply the accident, considered is denominated in many^ ways, of TO <r«M/3e^»i»cov. ^j^j^jj^ q^q jg ^^^^ which is spokcu of as subsisting