Monarchia (III, xii, 1-9)

(1) Ratione vero sic arguunt. Summunt etenim sibi principium de decimo Prime phylosophie dicentes: omnia que sunt unius generis reducuntur ad unum, quod est mensura omnium que sub illo genere sunt; sed omnes homines sunt unius generis: ergo debent reduci ad unum, tanquam ad mensuram omnium eorum. (1) Their argument based on reason runs as follows. Adopting a principle from the tenth book of the Metaphysics, they say: all things belonging to a single species are referred to one thing which is the measure for all things which belong to that species; but all men belong to the same species; therefore they are to be referred to one man as their common measure.
(2) Et cum summus Antistes et Imperator sint homines, si conclusio illa est vera, oportet quod reducantur ad unum hominem. Et cum Papa non sit reducendus ad alium, relinquitur quod Imperator cum omnibus aliis sit reducendus ad ipsum, tanquam ad mensuram et regulam: propter quod sequitur etiam idem quod volunt. (2) And since the supreme Pontiff and the Emperor are men, if that conclusion is valid, it must be possible to refer them to a single man. And since the Pope must not be referred to any other man, it remains that the Emperor along with all other men must be referred to him, as to their measure and rule; from this too the conclusion they want to reach does indeed follow.
(3) Ad hanc rationem solvendam dico quod, cum dicunt 'Ea que sunt unius generis oportet reduci ad aliquod unum de illo genere, quod est metrum in ipso', verum dicunt. Et similiter verum dicunt dicentes quod omnes homines sunt unius generis; et similiter verum concludunt cum inferunt ex his omnes homines esse reducendos ad unum metrum in suo genere. Sed cum ex hac conclusione subinferunt de Papa et Imperatore, falluntur 'secundum accidens'. (3) To refute this argument I say that, when they say "Those things which are of one species must be referred to a single thing of that species which is the measure for the species", they are correct. And similarly they are correct when they say that all men belong to a single species; and again they reach a correct conclusion when from these premisses they infer that all men are to be referred to a single measure for the species. But when from this conclusion they draw their inference concerning the Pope and the Emperor, they commit the accidental fallacy.
(4) Ad cuius evidentiam sciendum quod aliud est esse hominem et aliud est esse Papam; et eodem modo aliud est esse hominem, aliud esse Imperatorem, sicut aliud est esse hominem, et aliud est esse patrem et dominum. (4) To clarify this it must be borne in mind that it is one thing to be a man, another to be Pope; and in the same way it is one thing to be a man and another to be Emperor, just as it is one thing to be a man and another to be a father and a master.
(5) Homo enim est id quod est per formam substantialem, per quam sortitur spetiem et genus, et per quam reponitur sub predicamento substantie; pater vero est id quod est per formam accidentalem, que est relatio per quam sortitur spetiem quandam et genus, et reponitur sub genere 'ad aliquid', sive 'relationis'. Aliter omnia reducerentur ad predicamentum substantie, cum nulla forma accidentalis per se subsistat absque ypostasi substantie subsistentis: quod est falsum. (5) For man is what he is because of his substantial form, by virtue of which he belongs to a species and a genus and is placed in the category "substance"; whereas a father is what he is because of his accidental form, which consists of a relationship by virtue of which he belongs to a certain species and genus and comes into the category of "being related to", that is to say "relationship". If this were not so, everything would fall within the category "substance", inasmuch as no accidental form can have autonomous existence without being located in an existing substance; and this is false.
(6) Cum ergo Papa et Imperator sint id quod sunt per quasdam relationes, quia per Papatum et per Imperiatum, que relationes sunt altera sub ambitu paternitatis et altera sub ambitu dominationis, manifestum est quod Papa et Imperator, in quantum huiusmodi, habent reponi sub predicamento relationis, et per consequens reduci ad aliquod existens sub illo genere. (6) Since therefore Pope and Emperor are what they are by virtue of certain relationships, i.e. by virtue of Papal and Imperial office, which are respectively relationships of "paternity" and of "lordship", it is clear that Pope and Emperor must be assigned as Pope and Emperor to the category of relationship, and as a consequence be referred to something within that category.
(7) Unde dico quod alia est mensura ad quam habent reduci prout sunt homines, et alia prout sunt et Papa et Imperator. Nam, prout sunt homines, habent reduci ad optimum hominem, qui est mensura omnium aliorum, et ydea ut dicam -- quisquis ille sit -- ad existentem maxime unum in genere suo: ut haberi potest ex ultimis ad Nicomacum. (7) So I am saying that there is one measure to which they are to be referred as men, and another as Pope and Emperor. For as men they are to be referred to the perfect man, who is the measure of all the others, and the model, as it were - whoever he might be - of what is most unified in his species, as we can deduce from the end of the Ethics.
(8) In quantum vero sunt relativa quedam, ut patet, reducenda sunt vel ad invicem, si alterum subalternatur alteri vel in spetie comunicant per naturam relationis, vel ad aliquod tertium, ad quod reducantur tanquam ad comunem unitatem. (8) Insofar as they are terms which express a relationship, as is obvious, they are either to be referred one to the other (if one is subordinate to the other, or if they are related to one another within the species by the type of relationship), or else to some third entity to which they are to be referred as to a common unity.
(9) Sed non potest dici quod alterum subalternetur alteri, quia sic alterum de altero predicaretur, quod est falsum; non enim dicimus 'Imperator est Papa', nec e converso. Nec potest dici quod comunicent in spetie, cum alia sit ratio Pape, alia Imperatoris, in quantum huiusmodi: ergo reducuntur ad aliquid in quo habent uniri. (9) But it cannot be maintained that one is subordinated to the other, because if this were the case one would be predicated of the other; and this is false, for we do not say "the emperor is pope", nor vice versa. Nor can it be said that they are related to one another within the species, for the pope's function is one thing and the emperor's another, precisely because they are pope and emperor; therefore they are to be referred to some other thing in which they find their unity.