ANICIUS MANLIUS SEVERINUS
MOST HONOURABLE, OF THE ILLUSTRIOUS ORDER OF
TO HIS SAINTLY MASTER AND REVEREND FATHER
JOHN THE DEACON HIS SON BOETHIUS
I HAVE been long and anxiously waiting for you to discuss with me the problem which was raised at the meeting. But since your duties have prevented your coming and I shall be for some time involved in my business engagements, I am setting down in writing what I had been keeping to say by word of mouth.
YOU no doubt remember how, when the letter  was read in the assembly, it was asserted that the Eutychians confess that Christ is formed from two natures but does not consist of them - whereas Catholics admit both propositions, for among followers of the true Faith He is equally believed to be of two natures and in two natures. Struck by the novelty of this assertion I began to inquire what difference there can be between unions formed from two natures and unions which consist in two natures, for the point which the bishop who wrote the letter refused to pass over because of its gravity, seemed to me of importance and not one to be idly and carelessly slurred over. On that occasion all loudly protested that the difference was evident, that there was no obscurity, confusion or perplexity, and in the general storm and tumult there was no one who really touched the edge of the problem, much less anyone who solved it.
I was sitting a long way from the man whom I especially wished to watch,  and if you recall the arrangement of the seats, I was turned away from him, with so many between us, that however much I desired it I could not see his face and expression and glean therefrom any sign of his opinion. Personally, indeed, I had nothing more to contribute than the rest, in fact rather less than more. I, no more than the others, had any view about the question at issue, while my possible contribution was less by one thing, namely, the false assumption of a knowledge that I had not got. I was, I admit, much put out, and being overwhelmed by the mob of ignorant speakers, I held my peace, fearing lest I should be rightly set down as insane if I held out for being sane among those madmen.  So I continued to ponder all the questions in my mind, not swallowing what I had heard, but rather chewing the cud of constant meditation. At last the door opened to my insistent, knocking, and the truth which I found cleared out of my way all the clouds of the Eutychian error. And with this discovery a great wonder came upon me at the vast temerity of unlearned men who use the cloak of impudent presumption to cover up the vice of ignorance, for not only do they often fail to grasp the point at issue, but in a debate of this kind they do not even understand their own statements, forgetting that the case of ignorance is all the worse if it is not honestly admitted. 
I turn from them to you, and to you I submit this little essay for your first judgment and consideration. If you pronounce it to be sound I beg you to place it among the other writings of mine which you possess; but if there is anything to be struck out or added or changed in any way, I would ask you to let me have your suggestions, in order that I may enter them in my copies just as they leave your hands. When this revision has been duly accomplished, then I will send the work on to be judged by the man to whom I always submit everything.  But since the pen is now to take the place of the living voice, let me first clear away the extreme and self-contradictory errors of Nestorius and Eutyches; after that, by God's help, I will temperately set forth the middle way of the Christian Faith. But since in this whole question of self-contradictory heresies the matter of debate is Persons and Natures, these terms most first be defined and distinguished by their proper differences.
Nature, then, may be affirmed either of bodies alone or of substances alone, that is, of corporeals or incorporeals, or of everything that is in any way capable of affirmation. Since, then, nature can be affirmed in three ways, it must obviously be defined in three ways. For if you choose to affirm nature of the totality of things, the definition will be of such kind as to include all things that are. It will accordingly be something of this kind: "Nature belongs to those things which, since they exist, can in some measure be apprehended by the mind." This definition, then, includes both accidents and substances, for they all can be apprehended by the mind. But I add "in some measure" because God and matter cannot be apprehended by mind, be it never so whole and perfect, but still they are apprehended in a measure through the removal of accidents. The reason for adding the words, "since they exist," is that the mere word "nothing" denotes something, though it does not denote nature. For it denotes, indeed, not that anything is, but rather non-existence; but every nature exists. And if we choose to affirm "nature" of the totality of things, the definition will be as we have given it above.
But if "nature" is affirmed of substances alone, we shall, since all substances are either corporeal or incorporeal, give to nature denoting substances a definition of the following kind: "Nature is either that which can act or that which can be acted upon." Now the power to act and to suffer belongs to all corporeals and the soul of corporeals; for it both acts in the body and suffers by the body. But only to act belongs to God and other divine substances.
Here, then, you have a further definition of what nature is as applied to substances alone. This definition comprises also the definition of substance. For if the word nature signifies substance, when once we have defined nature we have also settled the definition of substance. But if we neglect incorporeal substances and confine the name nature to corporeal substances so that they alone appear to possess the nature of substance - which is the view of Aristotle and the adherents both of his and various other schools - we shall define nature as those do who have only allowed the word to be applied to bodies. Now, in accordance with this view, the definition is as follows: "Nature is the principle of movement properly inherent in and not accidentally attached to bodies. I say "principle of movement" because every body has its proper movement, fire moving upwards, the earth moving downwards. And what I mean by "movement properly inherent and not accidentally attached" is seen by the example of a wooden bed which is necessarily borne downward and is not carried downward by accident. For it is drawn downward by weight and heaviness because it is of wood, i.e. an earthly material. For it falls down not because it is a bed, but because it is earth, that is, because it is an accident of earth that it is a bed; hence we call it wood in virtue of its nature, but bed in virtue of the art that shaped it.
Nature has, further, another meaning according to which we speak of the different nature of gold and silver, wishing thereby to point the special property of things; this meaning of nature will be defined as follows: "Nature is the specific difference that gives form to anything." Thus, although nature is described or defined in all these different ways, both Catholics and Nestorians firmly hold that there are in Christ two natures of the kind laid down in our last definition, for the same specific differences cannot apply to God and man.
But the proper definition of Person is a matter of very great perplexity. For if every nature has person, the difference between nature and person is a hard knot to unravel; or if person is not taken as the equivalent of nature but is a term of less scope and range, it is difficult to say to what natures it may be extended, that is, to what natures the term person may be applied and what natures are dissociate from it. For one thing is clear, namely that nature is a substrate of Person, and that Person cannot be predicated apart from nature.
We must, therefore, conduct our inquiry into these points as follows.
Since Person cannot exist apart from nature and since natures are either substances or accidents and we see that a person cannot come into being among accidents (for who can say there is any person of white or black or size?), it therefore remains that Person is properly applied to substances. But of substances, some are corporeal and others incorporeal. And of corporeals, some are living and others the reverse; of living substances, some are sensitive and others insensitive; of sensitive substances, some are rational and others irrational.  Similarly of incorporeal substances, some are rational, others the reverse (for instance the animating spirits of beasts); but of rational substances there is one which is immutable and impassible by nature, namely God, another which in virtue of its creation is mutable and passible except in that case where the Grace of the impassible substance has transformed it to the unshaken impassibility which belongs to angels and to the soul.
Now from all the definitions we have given it is clear that Person cannot be affirmed of bodies which have no life (for no one ever said that a stone had a person), nor yet of living things which lack sense (for neither is there any person of a tree), nor finally of that which is bereft of mind and reason (for there is no person of a horse or ox or any other of the animals which dumb and unreasoning live a life of sense alone), but we say there is a person of a man, of God, of all angel. Again, some substances are universal, others are particular. Universal terms are those which are predicated of individuals, as man, animal, stone, stock and other things of this kind which are either genera or species; for the term man is applied to individual men just as animal is to animals, and stone and stock to individual stones and stocks. But particulars are terms which are never predicated of other things, as Cicero, Plato, this stone from which this statue of Achilles was hewn, this piece of wood out of which this table was made. But in all these things person cannot in any case be applied to universals, but only to particulars and individuals; for there is no person of a man if animal or general, only the single persons of Cicero, Plato, or other single individuals are termed persons.
Wherefore if Person belongs to substances alone, and these rational, and if every nature is a substance, existing not in universals but in individuals, we have found the definition of Person, viz.: "The individual substance of a rational creature."  Now by this definition we Latins have described what the Greeks call hupstois. For the word person seems to be borrowed from a different source, namely from the masks which in comedies and tragedies used to signify the different subjects of representation. Now persona "mask" is derived from personare, with a circumflex on the penultimate. But if the accent is put on the antepenultimate  the word will clearly be seen to come from sonus "sound," and for this reason, that the hollow mask necessarily produces a larger sound. The Greeks, too, call these masks prsopa from the fact that they are placed over the face and conceal the countenance from the spectator: par to prs tos pas tthetthai. But since, as we have said, it was by the masks they put on that actors played the different characters represented in a tragedy or comedy - Hecuba or Medea or Simon or Chremes, so also all other men who could be recognized by their several characteristics were designated by the Latins with the term persona and by the Greeks with prsopa. But the Greeks far more clearly gave to the individual subsistence of a rational nature the name hupstasis, while we through want of appropriate words have kept a borrowed term, calling that persona which they call hupstass, but Greece with its richer vocabulary gives the name hupstasis to the individual subsistence. And, if I may use Greek in dealing with matters which were first mooted by Greeks before they came to be interpreted in Latin: a osai n mn tos kuthlou enai dnantai n d tos tmois ka kat mros mnois phstantai, that is: essences indeed can have a general existence in universals, but they have particular substantial existence in particulars alone. For it is from particulars that all our comprehension of universals is taken. Wherefore since subsistences are present in universals but acquire substance in particulars they rightly gave the name hupstasis to subsistences which acquired substance through the medium of particulars. For to no one using his eyes with any care or penetration will subsistence and substance appear identical.
For our equivalents of the Greek terms ososis osisthai are respectively subsistentia and subsistere, while their hupstasis phstasthai are represented by our substantia and substare. For a thing has subsistence when it does not require accidents in order to be, but that thing has substance which supplies to other things, accidents to wit, a substrate enabling them to be; for it "substands" those things so long as it is subjected to accidents. Thus genera and species have only subsistence, for accidents do not attach to genera and species. But particulars have not only subsistence but substance, for they, no more than generals, depend on accidents for their Being; for they are already provided with their proper and specific differences and they enable accidents to be by supplying them with a substrate. Wherefore esse and subsistere represent enai and osisthai, while, substare represents huphstasthai. For Greece is not, as Marcus Tullius  playfully says, short of words, but provides exact equivalents for essentia, subsistentia, substantia and persona - osa for essentia, ososis for subsistentia, hupstasis for substantia, prsopon for persona. But the Greeks called individual substances hupostseis because they underlie the rest and offer support and substrate to what are called accidents; and we in our term call them substances as being substrate - hupostseis, and since they also term the same substances prsop, we too may call them persons. So osa is identical with essence, ososis with subsistence, hupstasis with substance, prsopon with person. But the reason why the Greek does not use prsopon of irrational animals while we apply the term substance to them is this: This term was applied to things of higher value, in order that what is more excellent might be distinguished, if not by a definition of nature answering to the literal meaning of huphstasthai = substare, at any rate by the words hupstasis = substantia.
To begin with, then, man is essence, i.e. osa, subsistence, i.e. ososis, hupstasis, i.e. substance, prsopon, i.e. person: osa or essentia because he is, ososis or subsistence because he is not accidental to any subject, hupstasis or substance because be is subject to all the things which are not subsistences or ososeis, while he is prsopon or person because he is a rational individual. Next, God is osa or essence, for He is and is especially that from which proceeds the Being of all things. To Him belong ososis, i.e. subsistence, for He subsists in absolute independence, and huphstasthai, for He is substantial Being. Whence we go on to say that there is one osa or ososis, i.e. one essence or subsistence of the Godhead, but three hupostseis or substances. And indeed, following this use, men have spoken of One essence, three substances and three persons of the Godhead. For did not the language of the Church forbid us to say three substances in speaking of God,  substance might seem a right term to apply to Him, not because He underlies all other things like a substrate, but because, just as He excells above all things, so He is the foundation and support of things, supplying them all with osisthai or subsistence.
You must consider that all I have said so far has been for the purpose of marking the difference between Nature and Person, that is, osa and hupstasis. The exact terms which should be applied in each case must be left to the decision of ecclesiastical usage. For the time being let that distinction between Nature and Person hold which I have affirmed, viz. that Nature is the specific property of any substance, and Person the individual substance of a rational nature. Nestorius affirmed that in Christ Person was twofold, being led astray by the false notion that Person may be applied to every nature. For on this assumption, understanding that there were in Christ two natures, he declared that there were likewise two persons. And although the definition which we have already given is enough to prove Nestorius wrong, his error shall be further declared by the following argument. If the Person of Christ is not single, and if it is clear that there are in Him two natures, to wit, divine and human (and no one will be so foolish as to fail to include either in the definition), it follows that there must apparently be two persons; for Person, as has been said, is the individual substance of a rational nature.
What kind of union, then, between God and man has been effected? Is it as when two bodies are laid the one against the other, so that they are only joined locally, and no touch of the quality of the one reaches the other - the kind of union which the Greeks term kat parthesin "by juxtaposition"? But if humanity has been united to divinity in this way no one thing has been formed out of the two, and hence Christ is nothing. The very name of Christ, indeed, denotes by its singular number a unity. But if the two persons continued and such a union of natures as we have above described took place, there could be no unity formed from two things, for nothing could ever possibly be formed out of two persons. Therefore Christ is, according to Nestorius, in no respect one, and therefore He is absolutely nothing. For what is not one cannot exist either; because Being and unity are convertible terms, and whatever is one is. Even things which are made up of many items, such as a heap or chorus, are nevertheless a unity. Now we openly and honestly confess that Christ is; therefore we say that Christ is a Unity. And if this is so, then without controversy the Person of Christ is one also. For if He had two Persons He could not be one; but to say that there are two Christs is nothing else than the madness of a distraught brain. Could Nestorius, I ask, dare to call the one man and the one God in Christ two Christs? Or why does he call Him Christ who is God, if he is also going to call Him Christ who is man, when his combination gives the two no common factor, no coherence? Why does be wrongly use the same name for two utterly different natures, when, if he is compelled to define Christ, he cannot, as he himself admits, apply the substance of one definition to both his Christs? For if the substance of God is different front that of man, and the one name of Christ applies to both, and the combination of different substances is not believed to have formed one Person, the name of Christ is equivocal  and cannot be comprised in any definition. But in what Scriptures is the name of Christ ever made double? Or what new thing has been wrought by the coming of the Saviour? For the truth of the faith and the unwontedness of the miracle alike remain, for Catholics, unshaken. For how great and unprecedented a thing it is - unique and incapable of repetition in any other age - that the nature of Him who is God alone should come together with human nature which was entirely different from God to form from different natures by conjunction a single Person! But now, if we follow Nestorius, what happens that is new? "Humanity and divinity," quoth he, "keep their proper Persons." Well, when had not divinity and humanity each its proper Person? And when, we answer, will this not be so? Or wherein is the birth of Jesus more significant than that of any other child, if, the two Persons remaining distinct the natures also were distinct? For while the Persons remained so there could no more be a union of natures in Christ than there could be in any other man with whose substance, be it never so perfect, no divinity was ever united because of the subsistence of his proper person. But for the sake of argument let him call Jesus, i.e. the human person, Christ, because through that person God wrought certain wonders. Agreed. But why should he call God Himself by the name of Christ? Why should he not go on to call the very elements by that name? For through them in their daily movements God works certain wonders. Is it because irrational substances cannot possess a Person enabling them to receive the name of Christ? Is not the operation of God seen plainly in men of holy life and notable piety? There will surely be no reason not to call the saints also by that name, if Christ taking humanity on Him is not one Person through conjunction. But perhaps he will say, "I allow that such men are called Christs, but it is because they are in the image of the true Christ." But if no one Person has been formed of the union of God and man, we shall consider all of them just as true Christs as Him who, we believe, was born of a Virgin. For no Person has been made one by the union of God and man either in Him or in them who by the Spirit of God foretold the coming Christ, for which cause they too were called Christs. So now it follows that so long as the Persons remain, we cannot in any wise believe that humanity has been assumed by divinity. For things which differ alike in persons and natures are certainly separate, nay absolutely separate; man and oxen are not further separate than are divinity and humanity in Christ, if the Persons have remained. Men indeed and oxen are united in one animal nature, for by genus they have a common substance and the same nature in the collection which forms the universal.  But God and man will be at all points fundamentally different if we are to believe that distinction of Persons continues under difference of nature. Then the human race has not been saved, the birth of Christ has brought us no salvation, the writings of all the prophets have but beguiled the people that believed in them, contempt is poured upon the authority of the whole Old Testament which promised to the world salvation by the birth of Christ. It is plain that salvation has not been brought us, if there is the same difference in Person that there is in Nature. No doubt He saved that humanity which we believe He assumed; but no assumption can be conceived, if the separation abides alike of Nature and of Person. Hence that human nature which could not be assumed as long as the Person continued, will certainly and rightly appear incapable of salvation by the birth of Christ. Wherefore man's nature has not been saved by the birth of Christ - an impious conclusion. 
But although there are many weapons strong enough to wound and demolish the Nestorian view, let us for the moment be content with this small selection from the store of arguments available.
I must now pass to Eutyches who, wandering from the path of primitive doctrine, has rushed into the opposite error  and asserts that so far from our having to believe in a twofold Person in Christ, we must not even confess a double Nature; humanity, he maintains, was so assumed that the union with Godhead involved the disappearance of the human nature. His error springs from the same source as that of Nestorius. For just as Nestorius deems there could not be a double Nature unless the Person were doubled, and therefore, confessing the double Nature in Christ, has perforce believed the Person to be double, so also Eutyches denied that the Nature was not double unless the Person was double and since he did not confess a double Person, he thought it a necessary consequence that the Nature should be regarded as single. Thus Nestorius, rightly holding Christ's Nature to be double, sacrilegiously professes the Persons to be two; whereas Eutyches, rightly believing the Person to be single, impiously believes that the Nature also is single. And being confuted by the plain evidence of facts, since it is clear that the Nature of God is different from that of man, he declares his belief to be: two Natures in Christ before the union and only one after the union. Now this statement does not express clearly what he means. However, let us scrutinize his extravagance. It is plain that this union took place either at the moment of conception or at the moment of resurrection. But if it happened at the moment of conception Eutyches seems to think that even before conception He had human flesh, not taken from Mary but prepared insome other way, while the Virgin Mary was brought in to give birth to flesh that was not taken from her; that this flesh, which already existed, was apart and separate from the substance of divinity, but that when He was born of the Virgin it was united to God, so that the Nature seemed to be made one. Or if this be not his opinion, since he says that there were two Natures before the union and one after, supposing the union to be established by conception, an alternative view may be that Christ indeed took a body from Mary but that before He took it the Natures of Godhead and manhood were different: but the Nature assumed became one with that of Godhead into which it passed. But if he thinks that this union was effected not by conception but by resurrection, we shall have to assume that this too happened in one of two ways; either Christ was conceived and did not assume a body from Mary or He did assume flesh from her, and there were (until indeed He rose) two Natures which became one after the Resurrection. From these alternatives a dilemma arises which we will examine as follows: Christ who was born of Mary either did or did not take human flesh from her. If Eutyches does not admit that He took it from her, then let him say what manhood He put on to come among us - that which had fallen through sinful disobedience or another? If it was the manhood of that man from whom all men descend, what manhood did divinity invest? For if that flesh in which He was born came not of the seed of Abraham and of David and finally of Mary, let Eutyches show from what man's flesh he descended, since, after the first man, all human flesh is derived from human flesh. But if he shall name any child of man beside Mary the Virgin as the cause of the conception of the Saviour, he will both be confounded by his own error, and, himself a dupe, will stand accused of stamping with falsehood the very Godhead for thus transferring to others the promise of the sacred oracles made to Abraham and David  that of their seed salvation should arise for all the world, especially since if human flesh was taken it could not be taken from any other but Him of whom it was begotten. If, therefore, His human body was not taken from Mary but from any other, yet that was engendered through Mary which had been corrupted by disobedience, Eutyches is confuted by the argument already stated. But if Christ did not put on that manhood which had endured death in punishment for sin, it will result that of no man's seed could ever one have been born who should be, like Him, without punishment for original sin. Therefore flesh like His was taken from no man, whence it would appear to have been new-formed for the purpose. But did this flesh then either so appear to human eyes that the body was deemed human which was not really human, because it was not subject to any primal penalty, or was some new true human flesh formed as a makeshift, not subject to the penalty for original sin? If it was not a truly human body, the Godhead is plainly convicted of falsehood for displaying to men a body which was not real and thus deceived those who thought it real. But if flesh had been formed new and real and not taken from man, to what purpose was the tremendous tragedy of the conception? Where the value of His long Passion? I cannot but consider foolish even a human action that is useless. And to what useful end shall we say this great humiliation of Divinity was wrought if ruined man has not been saved by the conception and the Passion of Christ - for they denied that he was taken into Godhead? Once more then, just as the error of Eutyches took its rise from the same source as that of Nestorius, so it hastens to the same goal inasmuch as according to Eutyches also the human race has not been saved,  since man who was sick and needed health and salvation was not taken into Godhead. Yet this is the conclusion he seems to have drawn, if he erred so deeply as to believe that Christ's body was not taken really from man but from a source outside him and prepared for the purpose in heaven, for He is believed to have ascended with it up into heaven. Which is the meaning of the text: none hath ascended into heaven save Him who came down from heaven.
I think enough has been said on the supposition that we should believe that the body which Christ received was not taken from Mary. But if it was taken from Mary and the human and divine natures did not continue, each in its perfection, this may have happened in one of three ways. Either Godhead was translated into manhood, or manhood into Godhead, or both were so modified and mingled that neither substance kept its proper form. But if Godhead was translated into manhood, that has happened which piety forbids us to believe, viz. while the manhood continued in unchangeable substance Godhead was changed, and that which was by nature passible and mutable remained immutable, while that which we believe to be by nature immutable and impassible was changed into a mutable thing. This cannot happen on any show of reasoning. But perchance the human nature may seem to be changed into Godhead. Yet how can this be if Godhead in the conception of Christ received both human soul and body? Things cannot be promiscuously changed and interchanged. For since some substances are corporeal and others incorporeal, neither can a corporeal substance be changed into all incorporeal, nor call an incorporeal be changed into that which is body, nor yet incorporeals interchange their proper forms; for only those things can be interchanged and transformed which possess the common substrate of the same matter, nor can all of these so behave, but only those which can act upon and be acted on by each other. Now this is proved as follows: bronze can no more be converted into stone than it can be into grass, and generally no body call be transformed into any other body unless the things which pass into each other have a common matter and can act upon and be acted on by each other, as when wine and water are mingled both are of such a nature as to allow reciprocal action and influence. For the quality of water can be influenced in some degree by that of wine, similarly the quality of wine can be influenced by that of water. And therefore if there be a great deal of water but very little wine, they are not said to be mingled, but the one is ruined by the quality of the other. For if you pour wine into the sea the wine is not mingled with the sea but is lost in the sea, simply because the quality of the water owing to its bulk has been in no way affected by the quality of the wine, but rather by its own bulk has changed the quality of the wine into water. But if the natures which are capable of reciprocal action and influence are in moderate proportion and equal or only slightly unequal, they are really mingled and tempered by the qualities which are in moderate relation to each other. This indeed takes place in bodies but not in all bodies, but only in those, as has been said, which are capable of reciprocal action and influence and have the same matter subject to their qualities. For all bodies which subsist in conditions of birth and decay seem to possess a common matter, but all bodies are not capable of reciprocal action and influence. But corporeals cannot in any way be changed into incorporeals because they do not share in any common underlying matter which can be changed into this or that thing by taking on its qualities. For the nature of no incorporeal substance rests upon a material basis; but there is no body that has not matter as a substrate. Since this is so, and since not even those things which naturally have a common matter can pass over into each other unless they have the power of acting on each other and being acted upon by each other, far more will those things not suffer interchange which not only have no common matter but are different in substance, since one of them, being body, rests on a basis of matter, while the other, being incorporeal, cannot possibly stand in need of a material substrate.
It is therefore impossible for a body to be changed into an incorporeal species, nor will it ever be possible for incorporeals to be changed into each other by any process of mingling. For things which have no common matter cannot be changed and converted one into another. But incorporeal things have no matter; they can never, therefore, be changed about among themselves. But the soul and God are rightly believed to be incorporeal substances; therefore the human soul has not been converted into the Godhead by which it was assumed. But if neither body nor soul can be turned into Godhead, it could not possibly happen that manhood should be transformed into God. But it is much less credible that the two should be confounded together since neither can incorporality pass over to body, nor again, contrariwise, can body pass over into incorporality when these have no common matter underlying them which can be converted by the qualities of one of two substances.
But the Eutychians say that Christ consists indeed of two natures, but not in two natures, meaning, no doubt, thereby, that a thing which consists of two elements can so far become one, that the elements of which it is said to be made up disappear; just as, for example, when honey is mixed with water neither remains, but the one thing being spoilt by conjunction with the other produces a certain third thing, so that third thing which is produced by the combination of honey and water is said to consist of both, but not in both. For it can never consist in both so long as the nature of both does not continue. For it can consist of both even though each element of which it is compounded has been spoiled by the quality of the other; but it can never consist in both natures of this kind since the elements which have been transmuted into each other do not continue, and both the elements in which it seems to consist cease to be, since it consists of two things translated into each other by change of qualities.
But Catholics in accordance with reason confess both, for they say that Christ consists both of and in two natures. How this can be affirmed I will explain a little later. One thing is now clear; the opinion of Eutyches has been confuted on the ground that, although there are three ways by which the one nature can subsist of the two, viz. either the translation of divinity into humanity or of humanity into divinity or the compounding of both together, the foregoing train of reasoning proves that no one of the three ways is a possibility.
It remains for us to show how in accordance with the affirmation of Catholic belief Christ consists at once in and of both natures.
The statement that a thing consists of two natures bears two meanings; one, when we say that anything is a union of two natures, as e.g. honey and water, where the union is such that in the combination however the elements be confounded, whether by one nature changing into the other, or by both mingling with each other, the two entirely disappear. This is the way in which according to Eutyches Christ consists of two natures.
The other way in which a thing can consist of two natures is when it is so combined of two that the elements of which it is said to be combined continue without changing into each other, as when we say that a crown is composed of gold and gems. Here neither is the gold converted into gems nor is the gem turned into gold, but both continue without surrendering their proper form.
Things then like this, composed of various elements, we say consist also in the elements of which they are composed. For in this case we can say that a crown is composed of gems and gold, for gems and gold are that in which the crown consists. For in the former mode of composition honey and water is not that in which the resulting union of both consists.
Since then the Catholic Faith confesses that both natures continue in Christ and that they both remain perfect, neither being transformed into the other, it says with right that Christ consists both in and of the two natures; in the two because both continue, of the two because the One Person of Christ is formed by the union of the two continuing natures.
But the Catholic Faith does not hold the union of Christ out of two natures according to that sense which Eutyches puts upon it. For the interpretation of the conjunction out of two natures which he adopts forbids him to confess consistence in two or the continuance of the two either; but the Catholic adopts an interpretation of the consistence out of two which comes near to that of Eutyches, yet keeps the interpretation which confesses consistence in two.
"To consist of two natures" is therefore an equivocal or rather a doubtful term of double meaning denoting different things; according to one of its interpretations the substances out of which the union is said to have been composed do not continue, according to another the union effected of the two is such that both natures continue.
When once this knot of doubt or ambiguity has been untied, nothing further can be advanced to shake the true and solid content of the Catholic Faith, which is that the same Christ is perfect man and God, and that He who is perfect man and God is One God and Son of Man, that, however, quaternity is not added to the Trinity by the addition of human nature to perfect Godhead, but that one and the same Person completes the number of the Trinity, so that, although it was the manhood which suffered, yet God can be said to have suffered, not by manhood becoming Godhead but by manhood being assumed by Godhead. Further, He who is man is called Son of God not in virtue of divine but of human substance, which latter none the less was conjoined to Godhead in a unity of natures. And although thought is able to distinguish and combine the manhood and the Godhead, yet one and the same is perfect man and God, God because He was begotten of the substance of the Father, but man because He was engendered of the Virgin Mary. And further He who is man is God in that manhood was assumed by God, and He who is God is man in that God was clothed with manhood. And although in the same Person the Godhead which took manhood is different from the manhood which It took, yet the same is God and man. For if you think of man, the same is man and God, being man by nature, God by assumption. But if you think of God, the same is God and man, being God by nature, man by assumption. And in Him nature becomes double and substance double because he is God-man, and One Person since the same is man and God. This is the middle way between two heresies, just as virtues also hold a middle place.  For every virtue has a place of honour midway between extremes. For if it stands beyond or below where it should it ceases to be virtue. And so virtue holds a middle place.
Wherefore if the following four assertions can be said to be neither beyond or below reason, viz. that in Christ are either two Natures and two Persons as Nestorius says, or one Person and one Nature as Eutyches says, or two Natures but one Person as the Catholic Faith believes, or one Nature and two Persons, and inasmuch as we have refuted the doctrine of two Natures and two Persons in our argument against Nestorius and incidentally have shown that the one Person and one Nature suggested by Eutyches is impossible - since there has never been anyone so mad as to believe that His Nature was single but His Person double - it remains that the article of belief must be true which the Catholic Faith affirms, viz. that the Nature is double, but the Person one. But as I have just now remarked that Eutyches confesses two Natures in Christ before the union, but only one after the union, and since I proved that under this error lurked two opposite opinions, one, that the union was brought about by conception although the human body was certainly not taken from Mary; the other that the body taken from Mary formed part of the union by means of the Resurrection, I have, it seems to me, argued the twofold aspect of the case as completely as it deserves. What we have now to inquire is how it came to pass that two Natures were combined into one Substance.
Nevertheless there remains yet another question which can be advanced by those who do not believe that the human body was taken from Mary, but that the body was in some other way set apart and prepared, which in the moment of union appeared to be conceived and born of Mary's womb. For they say: if the body was taken from man while every man was, from the time of the first disobedience, not only enslaved by sin and death but also involved in sinful desires, and if his punishment for sin was that, although he was held in chains of death, yet at the same time he should be guilty because of the will to sin, why was there in Christ neither sin nor any will to sin? And certainly such a question is attended by a difficulty which deserves attention. For if the body of Christ was assumed from human flesh, it is open to doubt of what kind we must consider that flesh to be which was assumed.
In truth, the manhood which He assumed He likewise saved; but if He assumed such manhood as Adam had before sin, He appears to have assumed a human nature complete indeed, but one which was in no need of healing. But how can it be that He assumed such manhood as Adam had when there could be in Adam both the will and the desire to sin, whence it came to pass that even after the divine commands had been broken, he was still held captive to sins of disobedience? But we believe that in Christ there was never any will to sin, because especially if He assumed such a human body as Adam had before his sin, He could not be mortal, since Adam, had he not sinned, would in no wise have suffered death. Since, then, Christ never sinned, it must be asked why, He suffered death if He assumed the body of Adam before sin. But if He accepted human conditions such as Adam's were after sin, it seems that Christ could not avoid being subject to sin, perplexed by passions, and, since the canons of judgment were obscured, prevented from distinguishing with unclouded reason between good and evil, since Adam by his disobedience incurred all these penalties of crime.
To whom we must reply  that there are three states of man to envisage: one, that of Adam before his sin, in which, though free from death and still unstained by any sin, he could yet have within him the will to sin; the second, that in which he might have suffered change had he chosen to abide steadfastly in the commands of God, for then it could have been further granted him not only not to sin or wish to sin, but to be incapable of sinning or of the will to transgress. The third state is the state after sin, into which man needs must be pursued by death and sin and the sinful will. Now the points of extreme divergence between these states are the following: one state would have been for Adam a reward if he had chosen to abide in God's laws; the other was his punishment because he would not abide in them; for in the former state there would have been no death nor sin nor sinful will, in the latter there was both death and sin and every desire to transgress, and a general tendency to ruin and a condition helpless to render possible a rise after the Fall. But that middle state from which actual death or sin was absent, but the power for both remained, is situate between the other two.
Each one, then, of these three states somehow supplied to Christ a cause for his corporeal nature; thus His assumption of a mortal body in order to drive death far from the human race belongs properly to that state which was laid on man by way of punishment after Adam's sin, whereas the fact that there was in Christ no sinful will is borrowed from that state which might have been if Adam had not surrendered his will to the frauds of the tempter. There remains, then, the third or middle state, to wit, that which was before death had come and while the will to sin might yet be present. In this state, therefore, Adam was able to eat and drink, digest the food be took, fall asleep, and perform all the other functions which always belonged to him as man, though they were allowed and brought with them no pain of death.
There is no doubt that Christ was in all points thus conditioned; for He ate and drank and discharged the bodily function of the human body. For we must not think that Adam was at the first subject to such need that unless he ate he could not have lived, but rather that, if he had taken food from every tree, he could have lived for ever, and by that food have escaped death; and so by the fruits of the Garden he satisfied a need.  And all know that in Christ the same need dwelt, but lying in His own power and not laid upon Him. And this need was in Him before the Resurrection, but after the Resurrection He became such that His human body was changed as Adam's might have been but for the bands of disobedience. Which state, moreover, our Lord Jesus Christ Himself taught us to desire in our prayers, asking that His Will be done as in heaven so on earth, and that His Kingdom come, and that He may deliver us from evil. For all these things are sought in prayer by those members of the human family who rightly believe and who are destined to undergo that most blessed change of all. 
So much have I written to you concerning what I believe should be believed. In which matter if I have said aught amiss, I am not so well pleased with myself as to try to press my effusions in the face of wiser judgment. For if there is no good thing in us there is nothing we should fancy in our opinions. But if all things are good as coming from Him who alone is good, that rather must be thought good which the Unchangeable Good and Cause of all Good indites.
 Evidently the letter addressed to Pope Symmachus by the Oriental bishops (vide Mansi, Concil. viii. 221ff.), in which they inquire concerning the safe middle way between the heresies of Eutyches and Nestorius. The date of the bishops' letter, and consequently, in all probability, of Boethius's tractate was 512.  Obviously his father-in-law Symmachus. Vide p. 76, eius cuius soleo iudicio, etc.  Cf. Hor. Serm. i. 3. 82; ii. 3. 40.  Cf. infra, de Cons. i. pr. 4 (p. 142) oportet uulnus delegas.  Vide supra, p. 75, and De Trin. p. 3.  For a similar example of the method of diuisio cf. Cic. De Off. ii. 3. 11. Cf. also Isag. Porph. edit. prima, i. 10. (ed. Brandt, p. 29).  Boethius's definition of persona was adopted by St. Thomas (S. ia iae. 29. 1), was regarded as classical by the Schoolmen, and has the approval of modern theologians. Cf. Dorner, Doctrine of Christ, iii.[p. 311.  Implying a short penultimate.  Tusc. ii. 15. 35.  For a similar submission of his own opinion to the usage of the Church cf. the end of Tr. i. and of Tr. ii.  Cf. the discussion of aequiuoca=omnumos in Isag. Porph. Vide Brandt's Index.  Vniuersalitas=to ka.  For a similar reductio ad absurdum ending in quod nefas est see Tr. iii.((supra, p. 44) and Cons. v. 3 (infra, p. 374).  The ecclesiastical via media, with the relegation of opposing theories to the extremes, which meet in a common fount of falsity, owes something to Aristotle and to our author. Vide infra, p. 118.  The use of this kind of argument by Boethius allays any suspicion as to the genuineness of Tr. iv. which might be caused by the use of allegorical interpretation therein. Note also that in the Consolatio the framework is allegory, which is also freely applied in the details.  Another reductio ad absurdum or ad impistotem, cf. supra, p. 98, note b.  Vide supra, p. 100 note.  This respondendum has the true Thomist ring.  Adam did not need to eat in order to live, but if he had not eaten he would have suffered hunger, etc.  The whole of this passage might be set in Tr. iv. without altering the tone.
 Obviously his father-in-law Symmachus. Vide p. 76, eius cuius soleo iudicio, etc.
 Cf. Hor. Serm. i. 3. 82; ii. 3. 40.
 Cf. infra, de Cons. i. pr. 4 (p. 142) oportet uulnus delegas.
 Vide supra, p. 75, and De Trin. p. 3.
 For a similar example of the method of diuisio cf. Cic. De Off. ii. 3. 11. Cf. also Isag. Porph. edit. prima, i. 10. (ed. Brandt, p. 29).
 Boethius's definition of persona was adopted by St. Thomas (S. ia iae. 29. 1), was regarded as classical by the Schoolmen, and has the approval of modern theologians. Cf. Dorner, Doctrine of Christ, iii.[p. 311.
 Implying a short penultimate.
 Tusc. ii. 15. 35.
 For a similar submission of his own opinion to the usage of the Church cf. the end of Tr. i. and of Tr. ii.
 Cf. the discussion of aequiuoca=omnumos in Isag. Porph. Vide Brandt's Index.
 Vniuersalitas=to ka.
 For a similar reductio ad absurdum ending in quod nefas est see Tr. iii.((supra, p. 44) and Cons. v. 3 (infra, p. 374).
 The ecclesiastical via media, with the relegation of opposing theories to the extremes, which meet in a common fount of falsity, owes something to Aristotle and to our author. Vide infra, p. 118.
 The use of this kind of argument by Boethius allays any suspicion as to the genuineness of Tr. iv. which might be caused by the use of allegorical interpretation therein. Note also that in the Consolatio the framework is allegory, which is also freely applied in the details.
 Another reductio ad absurdum or ad impistotem, cf. supra, p. 98, note b.
 Vide supra, p. 100 note.
 This respondendum has the true Thomist ring.
 Adam did not need to eat in order to live, but if he had not eaten he would have suffered hunger, etc.
 The whole of this passage might be set in Tr. iv. without altering the tone.