Disputationes metaphysicae

1. Aristotle treats of same and diverse, Metaphysics V, c. 9, and many place this among the distinct attributes of being, which we said above is comprehended under unity; and it is taken from Aristotle, Metaphysics X, text 9, cc. 5 and 6; and therefore at the end of these disputations on unity and multitude a few things are to be said of same and diverse, rather to explain the use of several words in this science than to add a new matter; for whatever pertains to the thing has been handed down in what we have said of unities and distinctions.

2. First, then, it is to be noticed that same can be said in two ways, namely relatively and negatively; or (as others speak) formally and fundamentally. For same formally taken seems to import a relation, in which it is most of all distinguished from unity; but negatively that is called the same which is not diverse or distinct from something; in which way it differs almost nothing from one, except that one expresses the negation of division in itself, but same expresses the negation of division from itself, or from that with which the being is said to be the same; on account of which Aristotle said, Metaphysics V, c. 9, text 16, that identity is a certain unity of being. And it is declared in that identity by which someone is said to be the same as himself; for, if this is taken relatively and formally, it expresses only a relation of reason, as is taken from Aristotle above, and it is the certain and common opinion, because there cannot be a real relation of the same thing to itself, because there must be a true opposition between relation and term, which cannot be of the same thing to itself; yet in this way, or formally, someone will not be said to be the same as himself, that is, to be referred to himself by such a relation, except when he is so conceived or compared through the intellect. But without any comparison or feigning of the intellect of this kind someone is said to be the same as himself fundamentally or negatively, because he is not diverse or divided from himself. And in this latter way identity can be numbered among the attributes of being, although that negation, as we were saying above, can be attributed not only to true being but also to feigned, and not only to being per se but also to any aggregate of beings or multitude and number; for any number whatever is the same as itself, as is one or unity. In another sense Scotus distinguished identity into absolute and relative, as Hervaeus reports, Quodlibet IV, q. 2; and Soncinas, Metaphysics X, q. 3; Javellus, q. 7; he calls absolute identity that by which one thing is said to be the same as itself, because there a respect to another thing is not implied; but he calls relative identity that by which one thing is said to be the same as another. And Scotus wishes, as the said authors report, that these two identities are distinct in reality, and in this they attack him. And indeed, if respective identity is taken between things distinct only by reasoned reason, as are man and Peter, that opinion is deservedly disproved, because the identity of Peter to himself, or to man or animal, do not differ in the thing, but as greater and lesser according to reason; otherwise the extremes themselves would have to be distinguished in the thing; but if respective identity is taken between things really distinct, and so the identity by which Peter is the same as himself is compared with that by which he is the same as Paul, then they can be called identities diverse in reality, since one is of the thing, the other of reason; but about names there is no need to care, since the thing is established.

3. Secondly it is to be observed from Aristotle above that identity is sometimes considered in some thing in itself, or with respect to itself; but sometimes in many compared among themselves, or in one thing compared with another. In the former way Peter is said to be the same in number with himself. But in the latter way he is the same in species with Paul, or the same in genus with the lion. And in this way Aristotle said, Metaphysics V, c. 9, that those things are the same which are one in something, either in genus, or in species, or in some analogous notion. The former identity, if it is considered as regards the negation or foundation, is identity simply, as also unity, because it is real identity; but in the respective notion it is only in a certain respect, because the relation of identity to itself is not real but of reason. But conversely the identity of several distinct things in a common notion (for we are speaking of creatures, to omit the identity of the three divine persons in one essence in number), as regards the foundation and as regards the negation of division, is only identity in a certain respect, or rather is a certain likeness, because it is only a unity of reason, as was shown above; but as regards the relation of identity this identity is thought to be simply so, because this relation, since it is between distinct things, is real according to the common conception of relations, of which we shall see below. And these indeed, as regards the thing, are general; but as regards the use of words, it is to be observed that this agreement of several things in a common notion has retained in substances the name of identity, simply speaking, from the accommodation of usage and as it were by antonomasia; but in qualities it is called likeness, in quantity equality, although this word signifies agreement not only in essential notion but also in magnitude; yet in all these, as there is the same mode of unity, so also the same formal notion of identity; and so all these are comprehended under same and diverse as they are taken transcendentally and attributed to being.

4. As many kinds of identity as of distinction.—Thirdly it is to be observed that, since same is said through the negation of division, either from itself, if one is said to be the same as himself, or between some two things, if they are said to be the same, as many modes of division or distinction as there are, so many modes of identity there can be, according to that saying: In as many ways as one of opposites is said, in so many can the other also be said. Whence it comes about that some things can be the same in thing, in mode and in reasoned reason; for by reasoning reason there is nothing which cannot be distinguished from itself, if it is in some way compared to itself; for if it is in no way conceived as several, it will now in no way be some things, but only something; whence Aristotle in the place cited says that identity is a certain unity either of several things, or when one uses one thing as several. But some things are the same in thing and in mode, yet not in reason; others can be the same according to the thing, yet not according to the mode; others finally are in no way the same according to the thing, but only according to reason. And hence it is understood, first, how same and diverse are opposed among themselves; for they are opposed first of all with respect to the same thing, not with respect to diverse ones, because they are opposed after the manner of relatives. Next they are opposed as compared to the same kind of distinction or division. Because a negation will not be opposed to an affirmation unless it is of the same according to the same; but these are opposed in so far as one includes the negation of the other; therefore to be the same in thing excludes to be really diverse, yet not to be diverse modally or by reason. And conversely, to be the same by reason does not exclude to be really distinct or diverse, because reason, as it distinguishes by concepts things which are the same in the thing, so conversely unites by a concept things which are diverse in the thing, as is evident from what was said above of universal unity.

5. But if you object that, although not every identity infers the negation of every diversity, nevertheless a greater identity seems to infer the negation of a greater diversity, as, if some things are modally the same, it is inferred not only that they are not modally diverse but also that they are not really diverse; but identity of reason seems to be the greatest; therefore modal and real identity is rightly inferred from it. The answer is that there is an equivocation in identity of reason; for it is not always the greatest; for there is a certain identity of reason which reason does not make but only conceives; and this is the greatest, because it supposes not only the actual negation of distinction in the thing but also the negation of a foundation or of virtual distinction; but there is another identity of reason which reason makes up, and this is not the greatest; indeed it is only in a certain respect, because it does not suppose in the thing identity simply, but only a foundation of likeness or agreement; and therefore this unity does not exclude diversity simply or according to the thing.

6. What to be distinguished, to differ and to be diverse are, and how they are compared among themselves.—But here it is necessary to beware of the equivocation of these terms, to be distinguished, to differ and to be diverse; for Aristotle says, Metaphysics V, c. 9, and Book X, c. 5, that to differ and to be diverse are not the same; for those things are said to differ which agree in something and are distinguished in something else; but those things too are said to be diverse which agree in nothing; whence to be diverse seems to be something superior to to differ, as the same Aristotle says, Book IV, c. 2. And in this breadth to be diverse is taken here; but to be distinct is also taken for the same as to be diverse; although in another acceptation, and one quite customary, to be distinct seems to express only the negation of real identity, but to be diverse seems also to add the negation of likeness and agreement, as one image is said to be distinct from another, however similar they are among themselves; whereas, when it is said to be diverse, not only this seems to be signified, but also that it is dissimilar or less perfect. But these, as I said, pertain only to the signification of words from the accommodation of usage, for of the thing it is sufficiently evident. In order, then, that same and diverse be opposed, they must be taken with proportion and with respect to the same thing, and in this way they include an immediate opposition, as one and many, as Aristotle said, Metaphysics IV, c. 2, because one includes the negation of the other.

7. And hence it is also evident how every being is the same or diverse, as Aristotle expressly says, Metaphysics X, c. 5, of which Soncinas says much there, qq. 5 and 6; Javellus, qq. 7 and 8; but it is an easy matter. For if these are taken relatively, it is not necessary that they belong to every being, because neither is a relation of reason necessary, as is self-evident, nor does one being always require another to which it is really referred by a real relation of identity or diversity, as is evident in God; for in the creature, because it depends essentially on God, there will always be a real relation of diversity or distinction, if such a relation is real. But if we speak (as it is necessary to speak truly) of fundamental or negative identity, or with respect to diverse things, every being is the same as itself and is diverse from every other, whether existing or possible, or even from feigned or imaginary being, because it can be denied of any of these; according to which sense many say that something is an attribute of being, because it signifies only division from every other. But with respect to the same thing, every being is the same as or diverse from it, if they are taken proportionately, for so they include a contradiction; but otherwise if the modes of identity and diversity are varied, as is sufficiently evident from what has been said. You will say: man and animal are neither the same nor diverse, because they are neither of the same genus or species, nor diverse, because they neither agree in the ultimate difference, and so cannot be of the same species, nor do they have opposite ultimate differences so as to be able to differ in species. The answer is that same and diverse with respect to the same thing are immediately opposed if they are taken as negatively or privatively opposed, but not as it were contrarily; as in the case proposed, if to be diverse in species is taken as it were only negatively, genus and species, or man and animal, can be said to be diverse in lowest species, because they are not constituted by the same ultimate difference. But if diverse in species is taken as it were positively and contrarily, then they are neither the same in species nor differ in species; and in similar proportion they are neither the same in genus nor diverse, but negatively they do not agree immediately in the same genus, and so can be said to be not of the same genus. When, therefore, these are said to be immediately opposed, the other extreme is to be taken negatively. Hence too to be opposed to another is thought to be an attribute of being, not indeed by relative opposition, which requires each extreme, but by fundamental opposition, in so far as every being has in itself some notion, difference or essence which excludes from it every other opposed or repugnant one. But this is to be understood either of opposition broadly taken, as it includes not only the four kinds posited by Aristotle in the Categories and in Books V and X of the Metaphysics, but also any repugnance whatever; or certainly it can be understood of the foundation of opposition, which at least suffices for contradiction with respect to any other whatever; and in this way nothing more is explained by the name of opposition than by the name of diversity. And so this property of being has been sufficiently declared.

8. Exposition of an Aristotelian pronouncement.—Finally it can be gathered from what has been said how that axiom which Aristotle posited, Metaphysics IV, is to be understood: Whatever things are the same as one third thing are the same as each other; for it is to be understood with proportion; for if they are the same in thing as one third thing, in a similar way they will be the same in thing as each other, but they will be able to be diverse in reason; but if they are the same in thing and reason as one third thing, they will in the same way be the same as each other. But this principle holds simply in creatures and in finite things; but in an infinite thing, such as is the divine essence, that maxim is not verified absolutely speaking, because on account of its infinity it can be the same as opposite relations which on account of their opposition cannot be the same among themselves except only in essence; of which elsewhere.