Sicut autem omne quod est in potentia potest dici materia, ita omne a quo aliquid habet esse, quodcumque esse sit, sive substantiale sive accidentale, potest dici forma: sicut homo cum sit potentia albus fit actu albus per albedinem, et sperma cum sit potentia homo fit actu homo per animam. Et quia forma facit esse in actu, ideo forma dicitur esse actus; quod autem facit actu esse substantiale est forma substantialis, et quod facit actu esse accidentale dicitur forma accidentalis. But, just as everything which is in potency can be called matter, so also everything from which something has existence (whether that existence be substantial or accidental) can be called form; for example, man, since he is white in potency, becomes actually white through whiteness, and sperm, since it is man in potency, becomes actually man through the soul. Also, because form causes existence in act, we say that the form is the act. However, that which causes substantial existence in act is called substantial form, and that which causes accidental existence in act is called accidental form. Et quia generatio est motus ad formam, duplici formae respondet duplex generatio: formae substantiali respondet generatio simpliciter, formae vero accidentali generatio secundum quid. Quando enim introducitur forma substantialis, dicitur aliquid fieri simpliciter; quando autem introducitur forma accidentalis, non dicitur aliquid fieri simpliciter sed fieri hoc: sicut quando homo fit albus, non dicimus simpliciter hominem fieri vel generari, sed fieri vel generari album. Et huic duplici generationi respondet duplex corruptio, scilicet simpliciter et secundum quid; generatio vero et corruptio simpliciter non sunt nisi in genere substantiae, sed generatio et corruptio secundum quid sunt in aliis generibus. Because generation is a motion to form, there is a twofold generation corresponding to this twofold form. Generation simply speaking corresponds to the substantial form, and generation in a certain respect corresponds to the accidental form. When a substantial form is introduced, we say that something comes into being simply speaking: for example, we say that man comes into being or man is generated. But when an accidental form is introduced, we do not say that something comes into being simply speaking, but that it comes into being as this. For example, when man comes into being as white, we do not say simply that man comes into being or is generated, but that he comes into being or is generated as white. There is a twofold corruption opposed to this twofold generation: simply speaking, and in a certain respect. Generation and corruption simply speaking are only in the genus of substance, but generation and corruption in a certain respect are in all the other genera. Et quia generatio est quaedam mutatio de non esse vel ente ad esse vel ens, e converso autem corruptio debet esse de esse ad non esse, non ex quolibet non esse fit generatio, sed ex non ente quod est ens in potentia: sicut idolum ex cupro, quod idolum est in potentia, non in actu. Also, because generation is a change from non-existence to existence, contrarily, corruption should be from existence to nonexistence. However, generation does not take place from just any non-being, but from the non-being which is being in potency. For example, a statue comes to be from bronze, which is a statue in potency and not in act. Ad hoc ergo quod sit generatio tria requiruntur: scilicet ens potentia quod est materia, et non esse actu quod est privatio, et id per quod fit actu, scilicet forma. Sicut quando ex cupro fit idolum, cuprum quod est potentia ad formam idoli est materia, hoc autem quod est infiguratum sive indispositum dicitur privatio; figura autem a qua dicitur idolum est forma, non autem substantialis quia cuprum ante adventum formae seu figurae habet esse in actu, et eius esse non dependet ab illa figura, sed est forma accidentalis: omnes enim formae artificiales sunt accidentales, ars enim non operatur nisi supra id quod iam constitutum est in esse perfecto a natura. In order that there be generation three things are required: being in potency, which is matter; non-existence in act, which is privation; and that through which something comes to be in act, which is form. For example, when a statue is made from bronze, the bronze which is in potency to the form of the statue is the matter; the shapeless or undisposed something is the privation; and the shape because of which it is called a statue is the form. But it is not a substantial form because the bronze, before it receives the shape, has existence in act, and its existence does not depend upon that shape. Rather, it is an accidental form, because all artificial forms are accidental. Art operates only on that which is already constituted in existence by nature. Capitulum 2 Chapter 2 The three principles of nature Sunt igitur tria principia naturae, scilicet materia, forma et privatio, quorum alterum, scilicet forma, est id ad quod est generatio, alia duo sunt ex parte eius ex quo est generatio. Unde materia et privatio sunt idem subiecto, sed differunt ratione; illud idem quod est aes est infiguratum ante adventum formae, sed ex alia ratione dicitur aes, et ex alia infiguratum. Unde privatio dicitur esse principium non per se sed per accidens, quia scilicet concidit cum materia; sicut dicimus quod hoc est per accidens medicus aedificat: non enim ex eo quod medicus, sed ex eo quod aedificator, quod concidit medico in uno subiecto. Therefore, there are three principles of nature: matter, form, and privation. One of these, form, is that by reason of which generation takes place; the other two are found on the part of that from which there is generation. Hence matter and privation are the same in subject but they differ in definition, because bronze and what is shapeless are the same before the advent of the form; but for one reason it is called bronze and for another reason it is called shapeless. Wherefore, privation is not said to be a principle essentially, but rather a principle accidentally, because it is coincident with matter. For example we say that it is accidental that the doctor builds, because he does not do this insofar as he is a doctor but insofar as he is a builder, which is coincident with being a doctor in the same subject. Sed duplex est accidens, scilicet necessarium quod non separatur a re, ut risibile hominis, et non necessarium quod separatur, ut album ab homine. Unde licet privatio sit principium per accidens, non sequitur quod non sit necessarium ad generationem, quia materia a privatione non denudatur; in quantum enim est sub una forma, habet privationem alterius et e converso, sicut in igne est privatio aeris et in aere privatio ignis. But there are two kinds of accidents: the necessary, which is not separated from the thing (for example, risible in man); and the non-necessary, which can be separated (for example, white from man). Thus, although privation is an accidental principle, still it does not follow that it is not necessary for generation, because matter is never entirely without privation. For insofar as it is under one form it has the privation of another, and conversely, just as there is the privation of fire in air and the privation of air in fire. Et sciendum quod, cum generatio sit ex non esse, non dicimus quod negatio sit principium, sed privatio; quia negatio non determinat sibi subiectum: ‘non videt’ enim potest dici etiam de non entibus, ut ‘chimaera non videt’, et iterum de entibus quae non nata sunt habere visum, sicut de lapidibus. Sed privatio non dicitur nisi de determinato subiecto, in quo scilicet natus est fieri habitus, sicut caecitas non dicitur nisi de his quae sunt nata videre. Also, we should note that, although generation is from non-existence, we do not say that negation is the principle but that privation is the principle, because negation does not determine a subject. Non-seeing can be said even of non-beings: for example, we say that the chimaera does not see, and we say the same of beings which are not apt to have sight, such as stones. But privation is said only of a determined subject: namely, that in which the habit is apt to come to be; for example, blindness is said only of those things which are apt to see. Et quia generatio non fit ex non ente simpliciter, sed ex non ente quod est in aliquo subiecto, et non in quolibet sed in determinato—non enim ex quolibet non igne fit ignis sed ex tali non igne circa quod nata sit fieri forma ignis—ideo dicitur quod privatio est principium. Sed in hoc differt ab aliis, quia alia sunt principia et in esse et in fieri: ad hoc enim quod fiat idolum oportet quod sit aes, et quod ultima sit figura idoli. Also, because generation does not come to be from non-being simply speaking, but from the non-being which is in some subject, and not in just any subject, but in a determined subject—because fire does not come to be from just any non-fire, but from such non-fire as is apt to receive the form of fire—therefore, we say that privation is the principle, and not negation. Privation differs from the other principles because the others are principles both in existence and in becoming. In order for a statue to come to be, there must be bronze; further, there must be the shape of the statue. Et iterum quando iam idolum est oportet haec duo esse; sed privatio est principium in fieri et non in esse, quia dum fit idolum oportet quod non sit idolum: si enim esset non fieret, quia quod fit non est, nisi in successivis. Sed ex quo iam idolum est, non est ibi privatio idoli, quia affirmatio et negatio non sunt simul, similiter nec privatio et habitus. Item privatio est principium per accidens, ut supra expositum est, alia duo sunt principia per se. Again, when the statue already exists, it is necessary that these two exist. But privation is a principle in becoming, and not in existing, because until the statue comes to be it must not be a statue. For, if it were, it would not come to be, because whatever comes to be is not, except in successive things: for example, in time and motion. But from the fact that the statue already exists, the privation of statue is not there, because affirmation and negation are not found together, and neither are privation and habit. Likewise, privation is an accidental principle, as was explained above, but the other two are essential principles. Ex dictis igitur patet quod materia differt a forma et a privatione secundum rationem. Materia enim est id in quo intelligitur forma et privatio, sicut in cupro intelligitur figura et infiguratum; quandoque quidem materia nominatur cum privatione, quandoque sine privatione: sicut aes cum sit materia idoli non importat privationem, quia ex hoc quod dico ‘aes’ non intelligitur indispositum seu infiguratum; sed farina cum sit materia respectu panis, importat in se privationem formae panis, quia ex hoc quod dico farinam significatur indispositio sive inordinatio opposita formae panis. Et quia in generatione materia sive subiectum permanet, privatio vero non, neque compositum ex materia et privatione, ideo materia quae non importat privationem est permanens, quae autem importat est transiens. Therefore, from what was said, it is plain that matter differs from form and privation by definition. Matter is that in which the form and privation are understood, just as in bronze the shape and the shapeless is understood. Still, matter sometimes designates privation and sometimes does not designate privation. For example, when bronze becomes the matter of the statue, it does not imply a privation, because when I speak of ‘bronze’ in this way I do not mean what is undisposed or shapeless. Flour, on the other hand, since it is the matter with respect to bread, implies in itself the privation of the form of bread, because when I say ‘flour’ the lack of disposition or the inordination opposed to the form of bread is signified. Also, because in generation the matter or the subject remains, but the privation does not (nor does the composite of matter and privation); therefore, that matter which does not imply privation is permanent, but that which implies privation is transient. Sed sciendum quod quaedam materia habet compositionem formae, sicut aes cum sit materia respectu idoli, ipsum tamen aes est compositum ex materia et forma, et ideo aes non dicitur materia prima quia habet materiam. Ipsa autem materia quae intelligitur sine qualibet forma et privatione, sed subiecta formae et privationi, dicitur materia prima, propter hoc quod ante ipsam non est alia materia: et hoc etiam dicitur yle. Et quia omnis definitio et omnis cognitio est per formam, ideo materia prima per se non potest cognosci vel definiri, sed per comparationem, ut dicatur quod illud est materia prima quod hoc modo se habet ad omnes formas et privationes sicut aes ad idolum et infiguratum: et haec dicitur simpliciter prima. Potest etiam aliquid dici materia prima respectu alicuius generis, sicut aqua est materia liquabilium, non tamen est prima simpliciter quia est composita ex materia et forma, unde habet materiam priorem. We should notice, too, that some matter has a composition of form: bronze, for example. For, although it is the matter with respect to the statue, the bronze itself is composed of matter and form. Therefore, bronze is not called prime matter, even though it has matter. However, that matter which is understood without any form and privation, but rather is subject to form and privation, is called ‘prime matter’ by reason of the fact that there is no other matter before it. This is also called hyle. Also, because all knowledge and every definition comes by way of the form, prime matter cannot be defined or known in itself but only through the composite. Consequently, it might be said that that is prime matter which is related to all forms and privations as bronze is to the statue and the shapeless; and this is called first simply speaking. A thing can also be called prime matter with respect to some genus, as water with respect to aqueous solutions; this, however, is not first simply speaking because it is composed of matter and form. Hence it has a prior matter. Et sciendum quod materia prima, et etiam forma, non generatur neque corrumpitur, quia omnis generatio est ad aliquid ex aliquo; id autem ex quo est generatio est materia, id ad quod est forma: si igitur materia vel forma generaretur, materiae esset materia et formae forma in infinitum. Unde generatio non est nisi compositi proprie loquendo. Note, also, that prime matter, and likewise form, is neither generated nor corrupted, because every generation goes from something to something. But that from which generation takes place is matter, and that in which generation terminates is form. Therefore, if matter and form were generated, there would be a matter of matter and a form of form, and so on forever. Hence, properly speaking, there is only generation of the composite. Sciendum est etiam quod materia prima dicitur una numero in omnibus. Sed unum numero dicitur duobus modis, scilicet quod habet unam formam determinatam in numero, sicut Socrates: et hoc modo materia prima non dicitur unum numero, cum in se non habeat aliquam formam. Dicitur etiam aliquid unum numero quia est sine dispositionibus quae faciunt differre secundum numerum: et hoc modo dicitur materia prima unum numero, quia intelligitur sine omnibus dispositionibus a quibus est differentia in numero. Again, notice that prime matter is said to be numerically one in all things. But to be numerically one can be said in two ways, such as that which has a determined numerically one form, like Socrates. Prime matter is not said to be numerically one in this way, since it does not have in itself a form. Also, something is said to be numerically one because it is without the dispositions which would cause it to differ numerically. Prime matter is said to be numerically one in this way because it is understood without all the dispositions which would cause it to differ numerically. Et sciendum quod, licet materia non habeat in sua natura aliquam formam vel privationem, sicut in ratione aeris neque est figuratum neque infiguratum, tamen nunquam denudatur a forma et privatione: quandoque enim est sub una forma, quandoque sub alia. Sed per se nunquam potest esse, quia, cum in ratione sua non habeat aliquam formam, non habet esse in actu, cum esse in actu non sit nisi a forma, sed est solum in potentia; et ideo quicquid est actu non potest dici materia prima. Notice, likewise, that, although prime matter does not have in its definition any form or privation (for example, neither shaped nor shapeless is in the definition of bronze), nevertheless, matter is never completely without form and privation, because it is sometimes under one form and sometimes under another. Moreover, it can never exist by itself: for, since it does not have any form in its definition, it cannot exist in act, since existence in act is only from the form. Rather, it exists only in potency. Therefore, whatever exists in act cannot be called prime matter. Capitulum 3 Chapter 3 The four causes Ex dictis igitur patet tria esse naturae principia, scilicet materia, forma et privatio; sed haec non sunt sufficientia ad generationem. Quod enim est in potentia non potest se reducere ad actum, sicut cuprum quod est potentia idolum non facit se idolum, sed indiget operante qui formam idoli extrahat de potentia in actum. Forma etiam non extraheret se de potentia in actum: et loquor de forma generati, quam diximus esse terminum generationis; forma enim non est nisi in facto esse, quod autem operatur est in fieri, idest dum res fit. Oportet ergo praeter materiam et formam esse aliquod principium quod agat, et hoc dicitur esse efficiens, vel movens, vel agens, vel unde est principium motus. From this it is plain, therefore, that there are three principles of nature: matter, form and privation. But these are not sufficient for generation. What is in potency cannot reduce itself to act: for example, the bronze which is in potency to being a statue cannot cause itself to be a statue. Rather, it needs an agent so that the form of the statue can pass from potency to act. Neither can the form draw itself from potency to act. I mean the form of the thing generated which we say is the term of generation, because the form exists only in that which has been made to be. However, what is made is in the state of becoming as long as the thing is coming to be. Therefore, it is necessary that besides the matter and form there be some principle which acts. This is called the efficient, moving, or agent cause, or that from which the principle of motion is. Et quia, ut dicit Aristoteles in II Metaphysicae, omne quod agit non agit nisi intendendo aliquid, oportet esse aliud quartum, id scilicet quod intenditur ab operante: et hoc dicitur finis. Et sciendum quod omne agens, tam naturale quam voluntarium, intendit finem; non tamen sequitur quod omne agens cognoscat finem, vel deliberet de fine. Cognoscere enim finem est necessarium in his quorum actiones non sunt determinatae, sed se habent ad opposita, sicut se habent agentia voluntaria; et ideo oportet quod cognoscant finem per quem suas actiones determinent. Sed in agentibus naturalibus sunt actiones determinatae, unde non est necessarium eligere ea quae sunt ad finem. Also, because, as Aristotle says in the second book of the Metaphysics, everything which acts, acts only by intending something, there must be some fourth thing: namely, that which is intended by the agent; and this is called the end. Again, we should notice that, although every agent, both natural and voluntary, intends an end, still it does not follow that every agent knows the end or deliberates about the end. To know the end is necessary in those whose actions are not determined, but which may act for opposed ends (as, for example, voluntary agents). Therefore, it is necessary that these know the end by which they determine their actions. But in natural agents the actions are determined; hence, it is not necessary to choose those things which are for the end. Et ponit exemplum Avicenna de citharaedo, quem non oportet de qualibet percussione chordarum deliberare, cum percussiones sint determinatae apud ipsum: alioquin esset inter percussiones mora, quod esset absonum. Magis autem videtur de operante voluntarie quod deliberet quam de agente naturali: et ita patet per locum a maiori quod possibile est agens naturale sine deliberatione intendere finem. Et hoc intendere nihil aliud erat quam habere naturalem inclinationem ad aliquid. Avicenna gives the following example. A harpist does not have to deliberate about the notes in any particular chord, since these are already determined for him; otherwise, there would be a delay between the notes, which would cause discord. However, it seems more reasonable to attribute deliberation to a voluntary agent than to a natural agent: and thus it is clear, by reasoning from the greater thing to the lesser, that a natural agent can intend the end without deliberation. Therefore, it is possible for the natural agent to intend the end without deliberation; and to intend this is nothing else than to have a natural inclination to something. Ex dictis ergo patet quod sunt quatuor causae, scilicet materialis, efficiens, formalis et finalis. Licet autem principium et causa dicantur convertibiliter, ut dicitur in V Metaphysicae, tamen Aristoteles in libro Physicorum ponit quatuor causas et tria principia. Causas autem accipit tam pro extrinsecis quam pro intrinsecis: materia et forma dicuntur intrinsecae rei eo quod sunt partes constituentes rem, efficiens et finalis dicuntur extrinsecae quia sunt extra rem; sed principia accipit solum causas intrinsecas. Privatio autem non nominatur inter causas, quia est principium per accidens, ut dictum est. Et cum dicimus quatuor causas, intelligimus de causis per se, ad quas tamen causae per accidens reducuntur, quia omne quod est per accidens reducitur ad id quod est per se. From the above it is plain that there are four causes: material, efficient, formal and final. But, although principle and cause are used convertibly, as is said in the fifth book of the Metaphysics, still, in the Physics, Aristotle gives four causes and three principles, because he takes as causes both what is extrinsic and what is intrinsic. Matter and form are said to be intrinsic to the thing because they are parts constituting the thing; the efficient and final causes are said to be extrinsic because they are outside the thing. But he takes as principles only the intrinsic causes. Privation, however, is not listed among the causes because it is an accidental principle, as was said. When we say that there are four causes we mean the essential causes, to which all the accidental causes are reduced, because everything which is accidental is reduced to that which is essential. Sed licet principia ponat Aristoteles pro causis intrinsecis in I Physicorum, tamen, ut dicitur in XI Metaphysicae, principium dicitur proprie de causis extrinsecis, elementum de causis quae sunt partes rei, id est de causis intrinsecis, causa dicitur de utrisque; tamen aliquando unum ponitur pro altero: omnis enim causa potest dici principium et omne principium causa. Sed tamen causa videtur addere supra principium communiter dictum, quia id quod est primum, sive consequatur esse posterius sive non, potest dici principium, sicut faber dicitur principium cultelli ut ex eius operatione est esse cultelli; sed quando aliquid movetur de nigredine ad albedinem, dicitur quod nigrum est principium illius motus, et universaliter omne id a quo incipit esse motus dicitur principium: tamen nigredo non est id ex quo consequatur esse albedo. Sed causa solum dicitur de illo primo ex quo consequitur esse posterioris: unde dicitur quod causa est ex cuius esse sequitur aliud; et ideo illud primum a quo incipit esse motus non potest dici causa per se, etsi dicatur principium. Et propter hoc privatio ponitur inter principia et non inter causas, quia privatio est id a quo incipit generatio; sed potest etiam dici causa per accidens, in quantum concidit materiae, ut supra expositum est. And, although Aristotle calls intrinsic causes ‘principles’ in the first book of the Physics, still, principle is applied properly to extrinsic causes, as is said in the eleventh book of the Metaphysics. ‘Element’ is used for those causes which are parts of the thing (namely, for the intrinsic causes). ‘Cause’ is applied to both. Nevertheless, one is sometimes used for the other: every cause can be called a principle and every principle a cause. However, cause seems to add something to principle as commonly used, because that which is primary, whether the existence of a posterior follows from it or not, can be called a principle: for example, the smith is called the principle of the knife because the existence of the knife comes from his operation. But when something is moved from whiteness to blackness, whiteness is said to be the principle of that motion; and universally, everything from which motion begins is called a principle. However, whiteness is not that from which the existence of blackness follows. But cause is said primarily only of that from which the existence of the posterior follows. Hence we say that a cause is that from whose existence another follows. Therefore, that primarily from which motion begins cannot really be called a cause, even though it may be called a principle. Because of this, privation is placed among the principles and not among the causes, because privation is that from which generation begins. But it can also be called an accidental cause insofar as it is coincident with matter, as was said above. Elementum vero non dicitur proprie nisi de causis ex quibus est compositio rei, quae proprie sunt materiales; et iterum non de qualibet causa materiali, sed de illa ex qua est prima compositio, sicut nec membra elementa sunt hominis, quia membra etiam sunt composita ex aliis: sed dicimus quod terra et aqua sunt elementa, quia haec non componuntur ex aliis corporibus, sed ex ipsis est prima compositio corporum naturalium. Unde Aristoteles in V Metaphysicae dicit quod elementum est id ex quo componitur res primo, et est in ea, et non dividitur secundum formam. Element, on the other hand, is applied properly only to the causes of which the thing is composed, which are properly the materials. Moreover, it is not said of just any material cause, but of that one of which a thing is primarily composed; for example, we do not say that the members of the body are the elements of man, because the members also are composed of other things. Rather, we say that earth and water are the elements, because these are not composed of other bodies, but natural bodies are primarily composed of them. Hence Aristotle says, in the fifth book of the Metaphysics, that an element is that of which a thing is primarily composed, which is in that thing, and which is not divided by a form. Expositio primae particulae, ex quo componitur res primo, patet per ea quae diximus. Secunda particula, scilicet et est in ea, ponitur ad differentiam illius materiae quae ex toto corrumpitur per generationem, sicut panis est materia sanguinis, sed non generatur sanguis nisi corrumpatur panis, unde panis non remanet in sanguine: unde non potest dici panis elementum sanguinis; sed elementa oportet aliquo modo manere cum non corrumpantur, ut dicitur in libro de Generatione. Tertia particula, scilicet et non dividitur secundum formam, ponitur ad differentiam eorum scilicet quae habent partes diversas in forma, id est in specie, sicut manus cuius partes sunt caro et ossa quae differunt secundum speciem; sed elementum non dividitur in partes diversas secundum speciem, sicut aqua cuius quaelibet pars est aqua. Non enim oportet ad esse elementi ut non dividatur secundum quantitatem, sed sufficit si non dividatur secundum speciem; et si etiam non dividatur, dicitur elementum, sicut litterae dicuntur elementa dictionum. Patet igitur quod principium quodammodo in plus habet se quam causa, et causa in plus quam elementum: et hoc est quod dicit Commentator in V Metaphysicae. The explanation of the first part of the definition, that of which a thing is primarily composed, is plain from the preceding. The second part, which is in that thing, differentiates it from that matter which is entirely corrupted by generation; for example, bread is the matter of blood, but blood is generated only by the corruption of bread. Thus bread does not remain in blood; and therefore bread cannot be called an element of blood. But the elements must remain in some way, since they are not entirely corrupted, as is said in the book On Generation. The third part, and which is not divided by a form, differentiates an element from those things which have parts diverse in form (that is, in species), as the hand whose parts are flesh and bone, which differ according to species. An element is not divided into parts diverse according to species: rather, it is like water whose every part is water. For an element to exist, it need not be undivided by quantity; rather, it is sufficient that it be undivided by form. Even if it is in no way divided, it is called an element, just as letters are the elements of words. This it is plain from what was said that ‘principle,’ in some way, applies to more than does ‘cause,’ and ‘cause’ to more than does ‘element.’ This is what the Commentator says in the fifth book of the Metaphysics. Capitulum 4 Chapter 4 Coincidence of causes Viso igitur quod quatuor sunt causarum genera, sciendum est quod non est impossibile quod idem habeat plures causas, ut idolum cuius causa est cuprum et artifex, sed artifex ut efficiens, cuprum ut materia. Non autem est impossibile ut idem sit causa contrariorum, sicut gubernator est causa salutis navis et submersionis, sed huius per absentiam, illius quidem per praesentiam. Now that we have seen that there are four genera of causes, we must understand that it is not impossible that the same thing have many causes. For example, the statue whose causes are both the bronze and the artist: the artist is the efficient cause while the bronze is the material cause. Nor is it impossible that the same thing be the cause of contraries; for example, the captain is the cause of the safety of the ship and of its sinking. He is the cause of the latter by his absence and of the former by his presence. Sciendum est etiam quod possibile est ut aliquid idem sit causa et causatum respectu eiusdem, sed diversimode: ut deambulatio est causa sanitatis ut efficiens, sed sanitas est causa deambulationis ut finis, deambulatio enim est aliquando propter sanitatem; et etiam corpus est materia animae, anima vero est forma corporis. Efficiens enim dicitur causa respectu finis, cum finis non sit in actu nisi per operationem agentis; sed finis dicitur causa efficientis, cum non operetur nisi per intentionem finis. Unde efficiens est causa illius quod est finis—ut sit sanitas—non tamen facit finem esse finem; et ita non est causa causalitatis finis, id est non facit finem esse finalem: sicut medicus facit sanitatem esse in actu, non tamen facit quod sanitas sit finis. Also, notice that it is possible that the same thing be a cause and the thing caused with respect to the same thing, but in diverse ways. For example, walking is sometimes the cause of health, as the efficient cause, but health is the cause of the walking, as the end: walking is sometimes on account of health. Also, the body is the matter of the soul, but the soul is the form of the body. The efficient cause is called a cause with respect to the end, since the end is actual only by the operation of the agent. But the end is called the cause of the efficient cause, since the efficient cause does not operate except by the intention of the end. Hence the efficient cause is the cause of that which is the end—for example, walking in order to be healthy. However, the efficient cause does not cause the end to be the end. Therefore, it is not the cause of the causality of the end; that is, it does not cause the end to be the final cause. For example, the doctor causes health to actually exist, but he does not cause health to be the end. Finis autem non est causa illius quod est efficiens, sed est causa ut efficiens sit efficiens; sanitas enim non facit medicum esse medicum—et dico sanitatem quae fit operante medico—sed facit ut medicus sit efficiens. Unde finis est causa causalitatis efficientis, quia facit efficiens esse efficiens; similiter facit materiam esse materiam et formam esse formam, cum materia non suscipiat formam nisi per finem, et forma non perficiat materiam nisi per finem. Unde dicitur quod finis est causa causarum, quia est causa causalitatis in omnibus causis. Also, the end is not the cause of that which is the efficient cause, but it is the cause of the efficient cause being an efficient cause. For example, health does not cause the doctor to be a doctor—I am speaking of the health which comes about by the doctor’s activity—but it causes the doctor to be an efficient cause. Therefore, the end is the cause of the causality of the efficient cause, because it causes the efficient cause to be an efficient cause. Likewise, the end causes the matter to be the matter and the form to be the form, since matter receives the form only for the sake of the end and the form perfects the matter only through the end. Therefore, we say that the end is the cause of causes, because it is the cause of the causality in all causes. Materia enim dicitur causa formae in quantum forma non est nisi in materia; et similiter forma est causa materiae in quantum materia non habet esse in actu nisi per formam: materia enim et forma dicuntur relative ad invicem, ut dicitur in II Physicorum; dicuntur enim ad compositum sicut partes ad totum et simplex ad compositum. Also, we say that matter is the cause of the form, insofar as the form exists only in matter. Likewise, the form is the cause of the matter, insofar as matter has existence in act only through the form, because matter and form are spoken of in relation to each other, as is said in the second book of the Physics. They are also spoken of in relation to the composite, as the part to the whole and as the simple to the composed. Sed quia omnis causa in quantum est causa naturaliter prior est causato, sciendum quod prius dicitur duobus modis, ut dicit Aristoteles in XVI de Animalibus: per quorum diversitatem potest aliquid dici prius et posterius respectu eiusdem et causa et causatum. Dicitur enim aliquid prius altero generatione et tempore, et iterum in substantia et complemento. Cum ergo naturae operatio procedat ab imperfecto ad perfectum et ab incompleto ad completum, imperfectum est prius perfecto secundum generationem et tempus, sed perfectum est prius in complemento: sicut potest dici quod vir est ante puerum in substantia et complemento, sed puer est ante virum generatione et tempore. But, because every cause, as cause, is naturally prior to that which it causes, notice that we say a thing is prior in two ways, as Aristotle says in the History of Animals XVI. Because of this diversity, we can call something prior and posterior with respect to the same thing, both the cause and the thing caused. We say that one thing is prior to another from the point of view of generation and time, and likewise from the point of view of substance and completeness. Since the operation of nature proceeds from the imperfect to the perfect and from the incomplete to the complete, the imperfect is prior to the perfect (namely, from the point of view of generation and time), but the perfect prior to the imperfect from the point of view of substance. For example, we can say that the man is before the boy according to substance and completeness, but the boy is before the man according to generation and time. Sed licet in rebus generabilibus imperfectum sit prius perfecto et potentia prior actu, considerando in aliquo eodem quod prius est imperfectum quam perfectum et in potentia quam in actu, simpliciter tamen loquendo oportet actum et perfectum prius esse, quia quod reducit potentiam ad actum actu est, et quod perficit imperfectum perfectum est. Materia quidem est prior forma generatione et tempore, prius enim est cui advenit quam quod advenit; forma vero est prior materia perfectione, quia materia non habet esse completum nisi per formam. Similiter efficiens prior est fine generatione et tempore, cum ab efficiente fiat motus ad finem; sed finis est prior efficiente in quantum est efficiens in substantia et complemento, cum actio efficientis non compleatur nisi per finem. Igitur istae duae causae, scilicet materia et efficiens, sunt prius per viam generationis, sed forma et finis sunt prius per viam perfectionis. But, although in generable things the imperfect is prior to the perfect and potency to act, when we consider that in one and the same thing the imperfect is prior to the perfect and potency to act, still, simply speaking, the act and the perfect must be prior, because it is what is in act that reduces potency to act and it is the perfect that perfects the imperfect. Matter is prior to form from the point of view of generation and time because that to which something comes is prior to that which comes to it. But form is prior to matter from the point of view of substance and completeness, because matter has completed existence only through the form. Likewise, the efficient cause is prior to the end from the point of view of generation and time, since the motion to the end comes from the efficient cause. But the end is prior to the efficient cause, insofar as it is the efficient cause from the point of view of substance and completeness, since the action of the efficient cause is completed only through the end. Therefore, these two causes, the material and the efficient, are prior by way of generation, but the form and the end are prior by way of perfection. Et notandum quod duplex est necessitas, scilicet necessitas absoluta et necessitas conditionalis. Necessitas quidem absoluta est quae procedit a causis prioribus in via generationis, quae sunt materia et efficiens, sicut necessitas mortis quae provenit ex materia et ex dispositione contrariorum componentium: et haec dicitur absoluta, quia non habet impedimentum; haec etiam dicitur necessitas materiae. Necessitas autem conditionalis procedit a causis posterioribus in generatione, scilicet a forma et fine, sicut dicimus quod necessarium est esse conceptionem si debeat generari homo; et ista est conditionalis, quia hanc mulierem concipere non est necessarium simpliciter, sed sub conditione: si debeat generari homo. Et haec dicitur necessitas finis. It must be noted that there are two kinds of necessity: absolute and conditional. Absolute necessity is that which proceeds from the causes prior by way of generation: the material and the efficient causes. An example of this is the necessity of death which comes from the matter: namely, the disposition of the composing contraries. This is called ‘absolute’ because it does not have an impediment. It is also called the necessity of matter. Conditional necessity, on the other hand, proceeds from causes posterior in generation: namely, the form and the end. For example, we say that conception is necessary if a man is to be generated. This is called ‘conditional’ because it is not necessary simply that this woman conceive, but only conditionally, namely, if a man is to be generated. This is called the necessity of the end. Et est sciendum quod tres causae possunt incidere in unum, scilicet forma, finis et efficiens, sicut patet in generatione ignis: ignis enim generat ignem, ergo ignis est causa efficiens in quantum generat; et iterum ignis est forma in quantum facit esse actu quod prius erat potentia; et iterum est finis in quantum est intentum ab agente et in quantum terminantur ad ipsum operationes ipsius agentis. Notice, also, that three causes can coincide in one thing—namely, the form, the end and the efficient cause—as is plain in the generation of fire. Fire generates fire; therefore, fire is the efficient cause insofar as it generates. Fire is also the formal cause insofar as it causes to exist actually that which before was in potency. Again, it is the end insofar as the operations of the agent are terminated in it and insofar as it is intended by the agent. Sed duplex est finis, scilicet finis generationis et finis rei generatae, sicut patet in generatione cultelli: forma enim cultelli est finis generationis, sed incidere quod est operatio cultelli, est finis ipsius generati, scilicet cultelli. Finis autem generationis concidit ex duabus dictis causis aliquando, scilicet quando fit generatio a simili in specie, sicut homo generat hominem et oliva olivam: quod non potest intelligi de fine rei generatae. But the end is twofold: the end of generation and the end of the thing generated, as is plain in the generation of a knife. The form of the knife is the end of generation; but cutting, which is the operation of the knife, is the end of the thing generated, namely, of the knife. Moreover, the end of generation sometimes is coincident with the two aforementioned causes: namely, when generation takes place from what is similar in species, as when man generates man and the olive, an olive. But this cannot be understood of the end of the thing generated.