Book 8

1.1. . . . But not even the most ancient of the philosophers were carried away toward disputing and being at a loss; how much less, surely, should we be—we who cling to the truly true philosophy, to whom the Scripture plainly enjoins, for the sake of discovery, to search out by inquiring? For the younger of the philosophers among the Greeks, out of an empty and unfulfilled love of honour, are carried off, at once refutatively and contentiously, into useless babbling; but the barbarian philosophy, by contrast, casting out all strife, said: "Seek, and you shall find; knock, and it shall be opened; ask, and it shall be given you." The reasoning that proceeds by question and answer, then, knocks at the door of truth as it appears, according to its inquiry; and when the obstacle is removed in the course of the search, scientific contemplation comes to be.

1.2. To those who knock in this way, I think, that which is sought is opened; and to those who in this way ask their questions according to the Scriptures, there comes, from God, the goal upon which they advance—the gift of God-given knowledge, apprehensively, through the inquiry that truly shines out by reason. For it is not possible to find without seeking; nor to seek without searching; nor to search without unfolding and laying open, by way of question, what is sought, leading it into clearness; nor again, having passed through the whole examination, not to receive at last the prize—the knowledge of the thing sought. But it is possible for the one who has sought to find, and he will seek if he first supposes that he does not know. Led, then, from here by longing toward the discovery of the noble, he seeks fair-mindedly, without contention, without love of glory—both asking and answering, and besides examining the very things said. For it befits those who hold fast not only to the divine Scriptures, but also to the common notions, to make their inquiries with discovery ending in some profitable conclusion. For another place and crowd awaits the turbulent among men and their vulgar word-mongering; but the lover and disciple of truth ought to be peaceable, even in his inquiries, approaching, through scientific demonstration, without self-love and with love of truth, toward apprehensive knowledge.

2.3. What other method, then, could be better or clearer for the beginning of such teaching than to go through, in discourse, the name proposed, so plainly that all who speak the same tongue can follow? Is, then, the name "demonstration" such a thing as "blityri"—a mere sound signifying nothing? And how is it that neither the philosopher, nor the orator, nor indeed the judge, brings forward "demonstration" as a meaningless name, nor does any of those at law fail to know its signification, that it does not exist? Indeed, the philosophers procure demonstration as something substantial, one in one way and another in another. Concerning everything sought, then, if one should rightly determine the matter, one would refer the discourse to no other beginning more agreed upon than that which is signified, out of its name, by common consent among all those of the same race and the same tongue. Then, setting out from here, one must inquire whether the thing signified, concerning which the discourse is, exists or not; and next, if it should be shown to exist, one must inquire exactly into its nature, of what sort it is, and whether perhaps it oversteps the rank assigned to it.

2.4. And since it does not suffice merely to state one's opinion about the thing sought (for it is open to the opponent equally to declare in turn what he wills), but one must confirm what is said: if the judgement of it should be referred to something likewise disputed, and that again likewise to another disputed thing, the matter will go on to infinity and will be indemonstrable; but if the confirmation of the thing not agreed upon should be referred to something agreed upon by all, that must be made the beginning of the teaching. Every name proposed, then, must be taken over into a discourse agreed upon and clear to those who share in the consideration—a discourse that will be the beginning of the teaching, and that will explain the discovery of the things sought. Come, then, let the name "sun" be proposed. The Stoics, then, say that this is "an intelligent kindling out of the waters of the sea." Is not their definition more obscure than the very name, needing another demonstration whether it is true? Better, then, to say, in common and clear discourse, that the sun is named "the brightest of the things that move through heaven"; for this discourse is more trustworthy, I think, and clearer, and equally agreed upon by all.

3.5. Likewise too all men would agree that demonstration is a discourse procuring conviction, for things disputed, out of things agreed upon. And not only demonstration and conviction and knowledge, but foreknowledge too is spoken of in two ways—the one scientific and firm, the other merely conjectural. In the strictest sense, then, that is called demonstration which implants scientific conviction in the souls of those who learn; the other is conjectural—just as a man, the one is truly a man who possesses the common faculties, while the other is wild and beastlike. So indeed the comic poet said: "How charming a thing is a man, when he is a man." And of an ox and a horse and a dog the same account holds, with reference to the virtue or vice of the animal. For looking toward the perfection of the genus, we come to the strictest of the things signified. Indeed, we conceive that man to be a physician who lacks nothing of the medical power, and that man a gnostic who lacks nothing of scientific knowledge.

3.6. And indication differs from syllogism in this: that the thing indicated is the disclosing of one thing, being itself one—as we say that being with child is an indication that one is no longer a virgin—while the thing taken by syllogism, being one, follows upon several—as, say, that Python betrayed the Byzantines, if so it chanced. Not one thing, but several, are taken as disclosing it. And to draw a conclusion from things agreed upon is to syllogize; but to conclude something from true premisses is to demonstrate; so that the benefit of demonstration is, as it were, a composite thing—both from taking, with reference to the things sought, premisses that are true, and from the conclusion's following upon them. But if either the former should not be the case, or the latter should not follow upon it, one has not demonstrated, but has syllogized. For to bring in the proper conclusion upon the premisses is to syllogize only; but for each of the premisses to be true is not to syllogize only, but also to have demonstrated. And to conclude is, as is plain from the word itself, to lead to the end; and the end, surely, in every discourse is the thing sought, which is also called the conclusion. And no simple and primary discourse is named a syllogism, even if it be true; but it is at the least composed of three such things—two as premisses, and one as conclusion. And either all things stand in need of demonstration, or some are trustworthy of themselves.

3.7. But if the former, then, demanding a demonstration of each demonstration, we shall go on to infinity, and so demonstration will be overturned; but if the latter, then these very things that are trustworthy of themselves will become the beginnings of demonstrations. Indeed the philosophers agree that the beginnings of the universe are indemonstrable. So that, if there is such a thing as demonstration, it is altogether necessary that there be first something trustworthy of itself, which is called primary and indemonstrable. To indemonstrable trustworthiness, then, all demonstration is referred back. And there would be also other beginnings of demonstrations, after the fountain that is from faith—the things that appear plainly to sense and to thought. For the things that fall to sense are simple and indissoluble; but the things relative to thought are simple and rational and primary; and the things begotten of them are composite, yet no less plain and trustworthy and more rational than the primary things. The natural power of distinguishing the consequent and the contradictory, which is proper to reason, all of us possess by nature. If, then, there should be found such a discourse as is able to procure, out of things already trustworthy, conviction for things not yet trustworthy, we shall say that this very thing is the substance of demonstration. And it has been said that the kind both of faith and of demonstration is twofold: the one producing only persuasion in the souls of the hearers, the other producing knowledge. If, then, one should begin from the things plain to sense and to thought, and then bring in the proper conclusion, he truly demonstrates; but if from things merely held in repute, yet not primary—that is, plain neither to sense nor to thought—then, if he bring in a proper conclusion, he will syllogize, but will not make the demonstration scientific; and if not a proper one, he will not even syllogize at all.

3.8. And demonstration differs from analysis. For each of the things demonstrated is demonstrated through certain things demonstrated, these too having been previously demonstrated by others, until we run back to the things trustworthy of themselves, or to the things plain to sense and thought—which is called analysis. But demonstration is when one arrives from the primary things at the thing sought, through all the things in between. The demonstrative man, then, must take much forethought for the truth of the premisses, but make no anxiety about the names—whether one wishes to call them axioms, or propositions, or premisses. Likewise, too, of what being laid down what is concluded, he must take much forethought; but whether one wishes to name his discourse concluding, or conclusive, or syllogistic, let him be least concerned. For these two things, I say, the demonstrative man must keep in all cases: to take true premisses, and to bring in upon them a consequent conclusion—which some also call the inference: the thing inferred upon the premisses. Concerning everything sought, in each particular problem, there is need of differing premisses, but proper to the thing proposed; and it is necessary to take over the thing proposed itself into a discourse, and this discourse must be agreed upon by all. But if the premisses be taken not proper to the problem, it is not possible to find out anything well concerning it, the whole nature of the problem—which is also called the question—being unknown. In all things sought, then, there is something previously known (which, being wholly trustworthy of itself, is believed without demonstration), which one must make the starting-point of the inquiry into them, and the criterion of the things that seem to have been found.

4.9. For every inquiry is conducted out of a knowledge previously existing. And it is possible for the knowledge that exists beforehand to be: sometimes of the substance bare, the works of the thing being unknown—as of stones, plants, animals, whose activities we do not know; or of their affections, or powers, or, in a word, of one of the things belonging to existing things. And sometimes one of these powers or affections, or some of these, is known—as the desires and passions of the soul—but the substance is unknown and sought. And in many cases, our very thought supposing all these things to itself, the inquiry is to which of the substances such a thing would belong. For having grasped in the understanding the conceptions of both—of the substance and of the activity—we thus come to the inquiry. And there are cases in which, knowing the activities together with the substances, we are ignorant of the affections. The method of discovery, then, is this: one must begin from the very recognition of the problems. For often the form of the expression deceives, and confounds and disturbs the understanding, so that it is not easy to find from what difference it is—as, for example, whether the thing conceived in the womb is an animal. For having some notion both of an animal and of the thing conceived, we inquire whether being an animal belongs to the thing conceived; and this is, whether to the conceived substance belongs the power to be moved and, further, to perceive. So that the inquiry is of activities and affections upon a substance previously known.

4.10. Straightway, then, one must put the question back to the one who proposes it: what, after all, does he call an animal? For this must especially be done when we see the name being led into different uses; and one must search out whether the thing signified by the name is disputed or agreed upon by all. For if he should say that he calls an animal whatever grows and is nourished, we shall again ask in turn whether he holds that plants too are animals; and then, if he says so, one must already show the thing conceived to be growing and nourished. For Plato calls plants too animals, as partaking of "the third kind of soul" alone, the appetitive; but Aristotle thinks that plants partake of the vegetative and nutritive soul, yet does not think fit to call them animals already; for he thinks that only what partakes of the other soul, the perceptive, deserves to be called an animal. The Stoics, however, do not name the vegetative power a soul at all. But if the one who proposes the question denies that plants too are animals, we shall show him saying things that contradict himself. For having defined the animal by being nourished and growing, but having declared that the plant too is not an animal, he seems to say nothing else than that the thing nourished and growing both is an animal and is not an animal. Let him say, then, what he wishes to learn: whether the thing in the womb grows and is nourished, or whether it has some share of perception or of self-impelled motion. For according to Plato the plant is ensouled and an animal; according to Aristotle, not yet an animal, for it lacks perception, but already ensouled. For with him the animal is an ensouled, perceptive substance. But according to the Stoics the plant is neither ensouled nor an animal; for the animal is an ensouled substance.

4.11. If, then, the animal is ensouled, and the soul is a perceptive nature, it is plain that the ensouled thing is already perceptive. If, then, the one who asked whether the thing in the womb is an animal, on being asked back, should say that he calls an animal that which is nourished and grows, he has his answer. But if he should declare that this is what he is seeking—whether the thing conceived is already perceptive, or is in some way self-impelled to motion—then the investigation of the matter becomes clear, the deceit about the name no longer remaining. But if he does not answer the counter-question, nor wishes to say what after all he means, or to what thing he is applying the name "animal" when he made his proposition, but bids us ourselves draw the distinction, he would be recognized as a wrangler. And if, there being two modes—one by question and answer, the other by continuous exposition—he refuses the one, let him give ear to all the things we go through into the problem; then, when we have finished, it will be open to him to take up each particular point in turn.

4.12. But if he should attempt to break in upon the examination by interrupting with questions, he plainly does not even wish to listen. But if he chooses to answer, first of all one must ask him to what thing he is applying the name "animal"; and when he has answered this, one must ask again what after all he signifies by "the thing conceived" or "the thing in the womb"—whether he wishes "the thing in the womb" to signify the things not yet fully formed and the seed itself once cast in, or only the things articulated and already fully formed, which are called embryos. And when he has answered this too, one must then conclude the matter in hand in order and teach it. But if he wishes us to speak, himself not answering, let him give ear: since you will not say with reference to what signification you say the thing you proposed (for in that case I would not have been making my discourse about things signified, but should already have been considering the very things themselves)—know that you have done something like what you would have done had you proposed the question whether the dog is an animal. For reasonably I would say: what dog? For I shall go through the land-dog and the sea-dog and the star in heaven called the Dog, and also Diogenes and the rest of the dogs in turn. For I could not divine whether you are asking about all, or about one. What, then, you will do later—to learn now about which you are inquiring—say plainly. But if you turn about names, the thing conceived—this very name—is plainly, to everyone, neither an animal nor a plant, but a name and a sound and a body and a being and a something, and anything rather than an animal. And if this is what you proposed, you have your answer.

4.13. Nor indeed is the thing signified by the name "conceived" an animal; rather, that is incorporeal, and a thing-said, and a matter, and a notion, and anything rather than an animal. And the nature of the animal would be something else; for it was plainly being shown of the very thing sought—I mean, of what sort the nature of the embryo is, this being a different problem from the one about the things signified by the name "animal." I say, then: if you call an animal that which is able to perceive and to be moved of its own impulse, then not simply that which is moved of its own impulse and perceives is an animal; for it is able also to sleep, or, when the objects of sense are not present, not to perceive. Rather, that which is able either to be impelled or to perceive by nature is the mark of an animal. For something of this sort is signified by these terms. First, whether the thing conceived is already able to perceive or to be moved of its own impulse—which is what is proposed for consideration; and second, whether the thing conceived will ever be able to perceive or to be moved of its own impulse—in which signification no one inquires, it being plain. But it was inquired whether the embryo is already an animal or still a plant. And then the name "animal" was taken over into a discourse, that it might be clear. Having found it differing from the non-animal by perception and self-impelled motion, we again distinguished this from the things lying near it, saying that one thing is that which is such in potency—which is not yet perceiving and being moved, but will at some time be such—and another is that which is already such in actuality; and of this, one is already in act, and the other is able to act but is at rest or sleeping. And this last is the thing sought. For one must not say that the embryo is an animal from its being nourished—which is of the substance—departing from the thing sought and attending to the things that otherwise belong to it.

4.14. And common to all the things said to be discovered is demonstration, which is a discourse confirming, out of certain things, some other thing. And the things out of which the thing sought must be confirmed must be agreed upon and known to the one who learns. And the beginning of all these is that which is plain to sense and to thought. The first demonstration, then, is composed out of these; but that which, from the things already shown to have been demonstrated through this, concludes again something else, is no less trustworthy than the former, yet cannot be named primary, because it is not concluded from primary propositions. The first kind of the difference among the things sought, there being three, has been shown—I mean, that (the substance being known) some of its works or affections are unknown; and the second difference of problems was that in which we all know the works and affections, but are ignorant of the substance—as, in what part of the body is the ruling faculty of the soul.

5.15. And the same attempt at demonstration holds also for the third problem. Some, then, say that it is not possible for there to be several beginnings of one animal. Now, of beginnings of the same kind, it is not possible that there be several for one animal; but that there be beginnings differing in their kinds is nothing absurd. Against the Pyrrhonists. If suspension of judgement says that nothing is firm, it is plain that, beginning from itself, it will first annul itself. Either, then, it grants that something is true and that one should not suspend judgement about all things; or it stands fast, saying that nothing is true—and then it is plain that it itself will not be speaking truth before all else. For either it speaks truth, or it does not. But if it speaks truth, it grants, unwillingly, that something is true; and if it does not speak truth, it leaves true the very things it wished to do away with. For in that whereby the annulling suspension is shown false, therein the things annulled are shown true—like the dream that says that all dreams are false. For being destructive of itself, it becomes confirmatory of the others. And altogether, if it is true, it will make its beginning from itself, being suspension of judgement not about anything else, but first about itself. And further, if a man apprehends that he is a man, or that he is suspending judgement, he plainly is not suspending judgement. And how would he even at the outset have come into the dispute, suspending judgement about all things? And how would he answer the thing asked? For about this very matter he is plainly not suspending judgement. Indeed, he even declares that he is suspending judgement; for which reason, even if one ought, in obedience to them, to suspend judgement about all things, we shall first suspend judgement about suspension itself—whether one ought to be persuaded by it or not.

5.16. Further, if this very thing is the truth—not to know the truth—then not even at the outset is anything true granted by him. But if he shall say that even this is disputable, namely, the being ignorant of the truth, then in this very thing he grants that the truth is knowable, in that he appears not to confirm the suspension of judgement about it. A school of thought is an inclination toward doctrines; or, as some say, an inclination toward many doctrines that have consistency with one another and with the appearances, tending toward living well. And a doctrine is a kind of rational apprehension; and apprehension is a settled disposition and assent of the understanding. And not only the suspenders of judgement, but every dogmatist too, is wont in certain matters to suspend judgement—either through weakness of mind, or through the unclearness of things, or through the equal strength of the arguments. The approaches and beginnings of inquiries are about these things and in these things.

6.17. One must set forth first, both for definitions and for demonstrations and for divisions, in how many senses the thing sought is spoken of; and the homonyms must be handled, and the synonyms set in order clearly according to their significations. Then one must inquire whether the thing proposed is among the things considered in relation to others, or is taken in itself. Besides these: whether it is, what it is, what has befallen it; or thus: whether it is, what it is, why it is. And toward the contemplation of these, the knowledge of particulars and that of universals contributes, together with the prior things and the divisions of them into their differences. Induction, then, brings the universal and the definition; the divisions bring the species and the essence and the individual; the contemplation of "in how many senses" brings the grasping of the proper; and the workings-through of difficulties bring the differences within them, and the demonstrations, and in other ways increase the contemplation, and the things consequent upon it. And out of all these, knowledge and truth are established. Again, the thing summed up out of division becomes a definition; for the definition is taken both before division and after it: before, when it is conceded or proposed; after, when it is demonstrated. And in respect of sense, too, the universal is summed up out of the particular; for the beginning of induction is sense, and the end is the universal. Induction, then, does not show what a thing is, but that it is or is not; division sets forth what a thing is; and definition, like division, teaches the substance and what a thing is, but not whether it is; while demonstration makes clear all three—whether it is, and what it is, and why it is. And there are some definitions that include the cause as well.

6.18. And since one knows scientifically when one sees the cause, and the causes are four—the matter, the moving cause, the form, the end—definition will be fourfold. One must take, then, first the genus, in which are the nearest of the things above; after this, the immediate difference. And the continuity of the differences, being cut and divided off, fills out the essence. And it is not necessary to state all the differences of each thing, but the species-making ones. Geometrical analysis and synthesis are like dialectical division and definition; and from division we run up to the simpler and more original things. For we divide the genus of the thing sought into the species existing in it—as, in the case of man, we divide the animal, being a genus, into the species appearing in it, the mortal and the immortal; and so, ever cutting the things that seem to be composite genera into the simpler species, we come to the thing sought, which no longer admits of division. For having divided the animal into the mortal and the immortal, and then the mortal into the land and the water animal, and again the land into the winged and the footed, and so, dividing the species nearest to the thing sought, which also includes the thing sought, we shall arrive, cutting, at the simplest species, which includes nothing else, but only the thing sought. For again we divide the footed into the rational and the irrational; and then, choosing out the species nearest to man among those taken from the division, and putting them together into one discourse, we render the definition of man, which is: an animal, mortal, land-dwelling, footed, rational.

6.19. Whence division holds, with respect to the definition, the rank of matter, searching out the simplicity of the name; while the definition holds the rank of the craftsman and maker, putting together and constructing and presenting the knowledge of the thing. And definitions are neither of the things themselves nor of the ideas, but, rather, of the things of which we have universal conceptions—of these conceptions we say that the definitions are the interpretative discourses; for of these conceptions the divisions too are made. And of divisions, one divides the thing divided into species, as a genus; another into parts, as a whole; and another into the accidents. The division of the whole into the parts is for the most part conceived in respect of magnitude; but the division into the accidents can never be wholly grasped, since indeed a substance too must by all means belong to each of the things that exist. Whence both these divisions are unapproved, and only the cutting of the genus into species is approved—by which is characterized both the sameness according to genus and the otherness according to the specific differences. The species is always contemplated in some part; not, however, conversely—if anything is a part of something, that thing will also be a species. For the hand is a part of man, but is not a species. And the genus exists within the species; for the animal is both in man and in ox; but the whole does not exist within the parts, for man does not exist in the feet. Therefore the species is more proper than the part; and whatever things are predicated of the genus, all these will be predicated of the species too.

6.20. Best, then, is it to divide the genus into two species; but if not, into three. The species, then, divided in a more generic way, are characterized by the same and the other; and then, divided through the generic significations, they are characterized. For each of the species is either a substance (as when we say: of existing things, some are bodies, others incorporeal), or a quantity, or a quality, or a relative, or a where, or a when, or to lie, or to have, or to do, or to be affected. He who is scientifically acquainted with anything whatever will render the definition of it as well; so that he who is unable to grasp and define anything in discourse could never be scientifically acquainted with it. And out of ignorance of the definition arise both the many disputes and the deceptions. For if the one who knows the thing has, in his understanding, the knowledge of it, and is able also to make clear in discourse what he conceives, and the interpretation of the conception is a definition—then it is necessary that the one who knows the thing be able to render its definition too.

6.21. And the difference is taken in addition to definitions, holding the rank of a sign in the definition. Thus, to the definition of man, the "capable of laughter" being added, makes the whole: an animal, rational, mortal, land-dwelling, footed, capable of laughter. For the things brought in by way of difference to the definition are signs of the proper things, but do not display the nature of the things themselves. Indeed they say that the difference is the giving of a property. And inasmuch as the thing that has the difference differs from all the rest by it—which belongs to it alone and is counter-predicated of the thing in the definitions—it is necessary to take over the first genus as foremost and substantial. In the longer definitions, then, there is the multitude of species found out through the ten categories; but in the shortest, the leading ones of the nearest species, being taken, signify the substance and nature of the thing. And the shortest is composed of three—the genus and two of the most necessary species. And this comes about for the sake of brevity. We say, then, man is the rational, laughing animal. And the thing especially belonging to the thing defined must be taken in addition—either its proper virtue, or its proper work, and certain other such things. The definition, then, being explanatory of the substance of the thing, is unable to grasp exactly the nature of the thing, but through the most proper species makes the disclosure of the substance; and the definition has the substance, as it were, in quality.

7.22. The causes that produce suspension of judgement are two, the highest: one, the manifold and unstable character of human judgement, which is by nature productive of discord—either of men with one another, or of themselves with themselves; the second, the discord in existing things, which also has reasonably become productive of suspension of judgement. For, being able neither to believe all impressions because of their conflict, nor to disbelieve all (because the statement that says that all are untrustworthy, being itself one of all, is circumscribed together with all), nor to believe some and disbelieve others because of their equality, we have been brought down to suspension of judgement. And of these very most original causes of suspension, the instability of the understanding is productive of discord, and discord is the immediate cause of suspension; whence life is full of law-courts and council-chambers and assemblies, and, in general, of the choosing and shunning of the so-called goods and evils—which are tokens of an understanding at a loss and shifting before the equal strength of the opposing things. And the chests of books are full, and the treatises and works of those who are in discord in their doctrines and have persuaded themselves that they know the truth in things.

8.23. There are three things concerning speech: the names, which are symbols of the notions primarily, and consequently of the underlying things; second, the notions, which are likenesses and impressions of the underlying things (whence the notions are the same for all, because the same impression is produced in all from the underlying things, but no longer the names, on account of the differing tongues); and third, the underlying things, from which the notions are impressed upon us. The names, then, are reduced by grammar to the twenty-four universal elements; for the elements must be determinate, since of particulars, being infinite, there is no knowledge, and it is the property of knowledge to rest upon universal and determinate considerations: whence the particulars are reduced to the universals. And the work of the philosophers is occupied with the notions and the underlying things. And since the particulars of these are infinite, certain elements of these too have been found, under which everything sought is brought. And if it should appear to have crept under some one of the elements, or several, we shall declare that it exists; but if it should escape all, that it nowhere is. Of the things said, some are said with combination, as "man runs"; others are said without combination, as "man" and as "runs," and all that do not complete a discourse, nor have the true or the false. And of the things said without combination, some signify substance, others quality, others quantity, others relation, others where, others when, others to lie, others to have, others to do, others to be affected—which we also call the elements of the things that are in matter and that are after the beginnings. For these are contemplated by reason, but the immaterial things are grasped by mind alone, in the first application.

8.24. Of the things ranked under the ten categories, some are said in themselves, as the nine categories; others are relatives. And again, of the things under these ten categories, some are synonyms, as ox and man, in respect of being animal; for synonyms are those of which both the name is common—the "animal"—and the discourse is the same, that is, the definition, namely, an ensouled substance. Heteronyms are all those that, concerning the same underlying thing, are in different names, as ascent and descent; for the road is the same, whether upward or downward. But the other kind of heteronyms, as horse and black, having both name and discourse different from one another, and not sharing in the underlying thing—these must be called "others," not heteronyms. Polyonyms are those that have the same discourse but a different name, as sword, blade, brand. Paronyms are those named with reference to something else, as the brave man from bravery. And homonyms are those using the same name, but not having the same discourse, as "man" the animal and "man" the painted figure. And of homonyms, some are homonymous by chance, as Ajax the Locrian and Ajax the Salaminian; others by intention, and of these some by likeness, as "man" the animal and the painted; some by analogy, as "the feet of Ida" and our own feet, because of being lower; some by activity, as the foot of a ship, by which the ship sails, and our own foot, by which we are moved. Things are also called homonymous from the same thing and toward the same thing, as the book and the lancet are called "medical" from the physician who uses them and with reference to the same discourse, the medical.

9.25. Of causes, some are antecedent, some sustaining, some co-operating, some "those-without-which." Antecedent are those that primarily furnish an occasion for something to come to be—as beauty does of love, to the intemperate; for, being seen by them, it produces only the amorous disposition, yet not by necessity. Sustaining are those which are also called, synonymously, self-complete, since they are of themselves sufficiently productive of the result. And next, all the causes must be shown in the case of the learner. The father is an antecedent cause of the learning; the teacher a sustaining cause; the nature of the learner a co-operating cause; and time holds the rank of the "those-without-which." And a cause is strictly said to be that which actively furnishes something, since we say that iron is cutting not only in the cutting, but also in the not cutting. So, then, "the thing that furnishes" signifies both: both that which is already acting, and that which is not yet, but possesses the power of acting.

9.26. Some, then, say that the causes are of bodies; others, of incorporeals. Some say that the body is strictly a cause, but the incorporeal so called by a misuse of terms and, as it were, in a cause-like way. Others reverse it, saying that incorporeals are strictly causes, and bodies only by misuse—as that the cutting, being an activity, is incorporeal, and is the cause of cutting, being an incorporeal activity; and of being cut, likewise, both to the knife and to the thing cut, which are bodies. The phrase "is a cause of certain things" is said in three ways: first, that which is the cause—as the statue-maker; second, that of which it is a cause—as of the statue's coming to be; third, that for which it is a cause, as for the matter; for to the bronze it is a cause of the statue's coming to be. The coming-to-be, then, and the being cut—the things of which it is a cause—being activities, are incorporeal. With reference to this account: causes are causes of predicates, or, as some say, of things-said (for Cleanthes and Archedemus call the predicates things-said); or, what is rather the case, some causes will be said to be of predicates, as of "is cut," whose noun-form is "the being cut," and others of propositions, as of "a ship comes to be," whose noun-form, again, is "the ship's coming to be." But Aristotle makes them causes of appellations, as of such things as house, ship, burning, cutting. And the noun-form is agreed to be incorporeal; for which reason too that sophism is solved thus: "What you say passes through your mouth"—which is true; "but you say 'house'; therefore a house passes through your mouth"—which is false. For we do not say the house, being a body, but the noun-form, being incorporeal, of which a house happens to be the case.

9.27. And we say that the builder builds, with reference to what is to come to be. Thus we say that a cloak is woven; for the thing that does is indicative of activity. And it is not the case that the thing that does is of one thing and the cause of another, but of the same; for inasmuch as it is a cause of coming-to-be, in that respect it is also productive of coming-to-be. The same thing, then, is both cause and productive. And if something is cause and productive, this is wholly also a "that-because-of-which"; but if something is a "that-because-of-which," it is not wholly also a cause. For many things run together toward one result, because of which the end comes to be, but not all are causes. For Medea would not have slain her children had she not been angered, nor would she have been angered had she not been jealous, nor this, had she not loved, nor this, had not Jason sailed to Colchis, nor this, had not the Argo been built, nor this, had not the timbers been cut from Pelion. For in all these, the "that-because-of-which" being present, not all are causes of the child-slaying, but only Medea. Therefore the thing that does not hinder is inactive; for which reason the thing that does not hinder is not a cause, but the thing that hinders. For in acting and doing something the cause is conceived.

9.28. Further, the thing that does not hinder is separated from the thing that comes to be (for the reason the thing is accomplished is that the thing able to hinder is not present), whereas the cause is toward the thing that comes to be; so that the thing that does not hinder would not be a cause. The cause is said in four ways: the thing that does, as the statue-maker; the matter, as the bronze; the form, as the impressed character; and the end, as the honour of the gymnasiarch. The bronze holds the rank of "those-without-which" toward the statue's coming to be, and is likewise a cause. For everything without which the result cannot come to be is by necessity a cause—but not a cause simply; for the "that-without-which" is not sustaining, but co-operating. Everything that acts furnishes the result with a fitness in the thing affected. For the cause disposes, and each thing is affected toward that for which it is by nature fitted, the fitness being furnishing and holding the rank of "those-without-which." The cause, then, is inactive without the fitness, but the fitness is not a cause, but a co-operator, since every cause is conceived in acting. And the earth would not make itself; so that it would not be a cause of itself. And it is ridiculous to say that the fire is not the cause of the burning, but the wood; nor the knife of the cutting, but the flesh; nor, of the athlete's being thrown, the strength of the opponent, but his own weakness. The sustaining cause needs no time; for the cautery, at the very instant of being pressed against the flesh, furnishes the pain. Of the antecedent causes, some need time until the result comes to be, others do not, as the fall in the case of a fracture. Surely, then, these are called timeless not by privation of time, but by diminution of it, as "the sudden" too, which itself does not come to be apart from time.

9.29. Every cause, as a cause, is grasped by a twofold understanding, since it is conceived both as of something and as toward something: of something, the result, as the knife of cutting; and toward something, the thing fitly disposed, as the fire toward the wood—for it will not burn the adamant. The cause is among relatives; for it is conceived in respect of its relation toward something else, so that we apply two things in order to conceive the cause as a cause. The same account holds also of the maker and producer and father. Nothing is itself a cause of itself, nor is anyone his own father, since then the first will become second. The cause acts and disposes; the thing that comes to be by the cause is affected and is disposed. But the same thing, taken with reference to itself, cannot at once act and be disposed, nor be son and father. And besides, the cause is prior in time, in respect of substance, to the thing that comes to be by it, as the knife to the cutting. But the same thing cannot, in the same respect, be both prior in time to the matter, in that it is a cause, and at the same time later and posterior in time, in that it is the work of the cause. And being differs from coming-to-be; so too the cause is of the thing that comes to be, the father of the son. For it is not possible for the same thing, in the same respect, both to be and to come to be at once. Nothing, then, is a cause of itself.

9.30. Causes are not causes of one another, but causes to one another. For the splenic disposition, lying beforehand, is not a cause of fever, but of the fever's coming to be; and the fever, lying beforehand, is not a cause of the spleen, but of the disposition's increasing. So too the virtues are causes to one another of not being separated, on account of their mutual implication; and the stones in an arch are causes to one another of the predicate "to remain," but are not causes of one another; and the teacher and the learner are causes to one another of the predicate "to advance." And things are said to be causes to one another sometimes of the same thing—as the merchant and the retailer are causes to one another of gaining; sometimes of one thing and another—as the knife and the flesh; for the one is to the flesh a cause of being cut, and the flesh to the knife a cause of cutting. "Eye for eye" and "life for life." For he who has struck someone a deadly blow is a cause to him of death, or of death's coming to be; but, struck back by him deadly, has him as a counter-cause—not in the same respect in which he became a cause to him, but in another. For he became to the man a cause of death; but it was not the death that in turn laid upon him the deadly counter-blow, but the man himself who was wounded; so that he himself became a cause of one thing, and had another as cause. And the one who has done wrong becomes a cause to the other of the wrong done to him; but the law that bids one be requited is a cause not of wrong, but to the one of vindication, and to the other of instruction. So that the causes are not causes of one another, as causes, but are causes to one another.

9.31. Further, it is inquired whether many causes, by concurrence of one result, become several causes. For the men who have come together are causes of the ship's being dragged down; but each is not a cause in his own right, but together with the rest—unless indeed the joint-cause too is a cause. Others say that, if there are many causes, each one in its own right becomes a cause of the one thing. Of being happy, at least, being one thing, the virtues, being many, are causes; and of being warmed and of feeling pain, likewise, the causes are many. Surely, then, the many virtues are one in power, and the things that warm and the things that cause pain are too. And the multitude of the virtues, being one in genus, becomes a cause of the one thing, being happy. But in truth several antecedent causes become causes of one thing, both in genus and in species: in genus, of falling ill in whatever way—as chilling, scorching, weariness, indigestion, drunkenness—and in species, of fever. But the sustaining causes are several in genus only, no longer also in species. For of being made sweet-smelling, being one in genus, the causes are many in species—as frankincense, rose, saffron, storax, myrrh, perfume; for the rose would not be so sweet-smelling as the myrrh.

9.32. And the same thing becomes a cause of contraries—sometimes in respect of the magnitude of the cause and its power, sometimes in respect of the fitness of the thing affected. In respect of the qualitative power: the same string, by tension or by slackening, gives back a high or a low note. In respect of the fitness of the things affected: honey is sweet to the healthy, but bitter to the feverish; and one and the same wine leads some toward anger, others toward relaxation; and the same sun melts the wax but dries the clay. Of causes, then, some are evident, taken by reckoning; others non-evident, taken by analogy. And of the non-evident, some are non-evident for a time—hidden at one season, but again at another seen plainly—and others non-evident by nature, never able to become evident at any season. And of the things non-evident by nature, some are apprehensible, which some called "not non-evident," being taken analogically through signs—as the proportion of the passages contemplated by reason; and others are inapprehensible, those that can in no way fall under apprehension, which indeed are called non-evident absolutely. And some causes are antecedent, others sustaining, others joint-causes, others co-operating; and some of that which is according to nature, others of that which is contrary to nature, others of disease; and, in respect of subordination, some of affections, others of their magnitude, others of times and seasons.

9.33. When, then, the antecedent causes are removed, the result remains; but a sustaining cause is one in whose presence the result remains, and on whose removal it is removed. And the sustaining is also called, synonymously, self-complete, since it is of itself sufficiently productive of the result. And if the self-complete cause is indicative of a self-complete activity, the co-operating signifies a service and a ministry along with another. If, then, it furnishes nothing, it will not even be called co-operating; but if it furnishes something, it becomes by all means a cause of that which it furnishes—that is, of the thing that comes to be through it. The co-operating, then, is that in whose presence the result came to be—an evident thing in the presence of an evident, a non-evident in that of a non-evident. And the joint-cause too is of the kind of the causes, just as the fellow-soldier is a soldier and the fellow-ephebe an ephebe. The co-operating cause, then, helps the sustaining toward the intensifying of that which comes to be through it; but the joint-cause is not of the same conception. For there can be a joint-cause even if something is not a sustaining cause; for the joint-cause is conceived along with another that is not itself able, in its own right, to produce the result—being a cause along with a cause. And the co-operating differs from the joint-cause in this: that the joint-cause furnishes the result with another that does not, in its own right, produce it; while the co-operating, not producing it in its own right, but coming to another that does produce it in its own right, co-operates with that other toward the result's coming to be more vehemently. And especially does the having become co-operating out of an antecedent set forth that the power of the cause extends to the co-operating.