§4.3Σκοπεῖν δὲ καὶ εἰ τὸ ἐν τῷ γένει κείμενον μετέχει τινὸς ἐναντίου τῷ γένει ἢ εἰ ἐνδέχεται μετέχειν· τὸ γὰρ αὐτὸ τῶν ἐναντίων ἅμα μεθέξει, ἐπειδὴ τὸ μὲν γένος οὐδέποτ᾿ ἀπολείπει, μετέχει δὲ καὶ τοὐναντίου ἢ ἐνδέχεται μετέχειν.
One must also examine whether what is placed in the genus partakes of some contrary to the genus, or if it is capable of partaking of it; for the same thing will at the same time partake of contraries, since the genus never leaves it, and it also partakes of, or is capable of partaking of, the contrary.
Ἔτι εἴ τινος κοινωνεῖ τὸ εἶδος, ὃ ἀδύνατον ὅλως ὑπάρχειν τοῖς ὑπὸ τὸ γένος.
Moreover, if the species shares in something which is altogether impossible to belong to the things under the genus.
Οἷον εἰ ἡ ψυχὴ τῆς ζωῆς κοινωνεῖ, τῶν δ᾿ ἀριθμῶν μηδένα δυνατὸν ζῆν, οὐκ ἂν εἴη εἶδος ἀριθμοῦ ἡ ψυχή.
For example, if the soul shares in life, and it is impossible for any of the numbers to live, the soul would not be a species of number.
Σκεπτέον δὲ καὶ εἰ ὁμώνυμον τὸ εἶδος τῷ γένει, στοιχείοις χρώμενον τοῖς εἰρημένοις πρὸς τὸ ὁμώνυμον· συνώνυμον γὰρ τὸ γένος καὶ τὸ εἶδος.
One must also examine whether the species is homonymous with the genus, using the principles already mentioned in connection with homonyms; for the genus and the species are synonymous.
Ἐπεὶ δὲ παντὸς γένους εἴδη πλείω, σκοπεῖν εἰ μὴ ἐνδέχεται ἕτερον εἶδος εἶναι τοῦ εἰρημένου γένους· εἰ γὰρ μή ἐστι, δῆλον ὅτι οὐκ ἂν εἴη ὅλως γένος τὸ εἰρημένον.
And since there are more species than one of every genus, one must see if it is not possible for there to be another species of the mentioned genus; for if there is not, it is clear that the mentioned thing would not be a genus at all.
Σκοπεῖν δὲ καὶ εἰ τὸ μεταφορᾷ λεγόμενον ὡς γένος ἀποδέδωκεν, οἷον τὴν σωφροσύνην συμφωνίαν· πᾶν γὰρ γένος κυρίως κατὰ τῶν εἰδῶν κατηγορεῖται, ἡ δὲ συμφωνία κατὰ τῆς σωφροσύνης οὐ κυρίως ἀλλὰ μεταφορᾷ· πᾶσα γὰρ συμφωνία ἐν φθόγγοις.
One must also examine whether he has assigned what is spoken of metaphorically as a genus, as "temperance" as "harmony"; for every genus is predicated of its species in its proper sense, but "harmony" is predicated of "temperance" not in its proper sense but metaphorically; for all harmony is in sounds.
Ἔτι ἂν ᾖ ἐναντίον τι τῷ εἴδει, σκοπεῖν.
Moreover, if there is any contrary to the species, one must examine it.
Ἔστι δὲ πλεοναχῶς ἡ σκέψις, πρῶτον μὲν εἰ ἐν τῷ αὐτῷ γένει καὶ τὸ ἐναντίον, μὴ ὄντος ἐναντίου τῷ γένει· δεῖ γὰρ τὰ ἐναντία ἐν τῷ αὐτῷ γένει εἶναι, ἂν μηδὲν ἐναντίον τῷ γένει ᾖ.
The examination is conducted in several ways: first, whether the contrary also is in the same genus, when there is no contrary to the genus; for contraries must be in the same genus, if there is no contrary to the genus.
Ὄντος δ᾿ ἐναντίου τῷ γένει, σκοπεῖν εἰ τὸ ἐναντίον ἐν τῷ ἐναντίῳ· ἀνάγκη γὰρ τὸ ἐναντίον ἐν τῷ ἐναντίῳ εἶναι, ἄνπερ ᾖ ἐναντίον τι τῷ γένει.
But if there is a contrary to the genus, one must see if the contrary is in the contrary; for it is necessary that the contrary should be in the contrary, if indeed there is any contrary to the genus.
Φανερὸν δὲ τούτων ἕκαστον διὰ τῆς ἐπαγωγῆς.
And each of these is clear through induction.
Πάλιν εἰ ὅλως ἐν μηδενὶ γένει τὸ τῷ εἴδει ἐναντίον, ἀλλ᾿ αὐτὸ γένος, οἷον τἀγαθόν· εἰ γὰρ τοῦτο μὴ ἐν γένει, οὐδὲ τὸ ἐναντίον τούτου ἐν γένει ἔσται, ἀλλ᾿ αὐτὸ γένος, καθάπερ ἐπὶ τοῦ ἀγαθοῦ καὶ τοῦ κακοῦ συμβαίνει· οὐδέτερον γὰρ τούτων ἐν γένει, ἀλλ᾿ ἑκάτερον αὐτῶν γένος.
Again, if the contrary to the species is altogether in no genus, but is itself a genus, as "the good"; for if this is not in a genus, neither will its contrary be in a genus, but will itself be a genus, as happens in the case of the good and the bad; for neither of these is in a genus, but each of them is a genus.
Ἔτι εἰ ἐναντίον τινὶ καὶ τὸ γένος καὶ τὸ εἶδος, καὶ τῶν μὲν ἔστι τι μεταξύ, τῶν δὲ μή.
Moreover, if both the genus and the species are contrary to something, and of the one there is an intermediate, but of the other there is not.
Εἰ γὰρ τῶν γενῶν ἔστι τι μεταξύ, καὶ τῶν εἰδῶν, καὶ εἰ τῶν εἰδῶν, καὶ τῶν γενῶν, καθάπερ ἐπ᾿ ἀρετῆς καὶ κακίας καὶ δικαιοσύνης καὶ ἀδικίας· ἑκατέρων γὰρ ἔστι τι μεταξύ.
For if there is an intermediate between the genera, there is also between the species, and if between the species, also between the genera, as in the case of virtue and vice, and justice and injustice; for there is an intermediate between both pairs.
Ἔνστασις τούτου ὅτι ὑγιείας καὶ νόσου οὐδὲν μεταξύ, κακοῦ δὲ καὶ ἀγαθοῦ.
An objection to this is that there is nothing intermediate between health and disease, but there is between bad and good.
Ἢ εἰ ἔστι μέν τι ἀμφοῖν ἀνὰ μέσον, καὶ τῶν εἰδῶν καὶ τῶν γενῶν, μὴ ὁμοίως δέ, ἀλλὰ τῶν μὲν κατὰ ἀπόφασιν τῶν δ᾿ ὡς ὑποκείμενον.
Or if there is indeed something intermediate between both, i.e. both between the species and between the genera, but not in a similar way, but of the one by negation and of the other as a subject.
Ἔνδοξον γὰρ τὸ ὁμοίως ἀμφοῖν, καθάπερ ἐπ᾿ ἀρετῆς καὶ κακίας καὶ δικαιοσύνης καὶ ἀδικίας· ἀμφοῖν γὰρ κατὰ ἀπόφασιν τὰ ἀνὰ μέσον.
For it is an accepted opinion that it should be similar for both, as in the case of virtue and vice, and justice and injustice; for the intermediates between both are by negation.
Ἔτι ὅταν μὴ ᾖ ἐναντίον τῷ γένει, σκοπεῖν μὴ μόνον εἰ τὸ ἐναντίον ἐν τῷ αὐτῷ γένει, ἀλλὰ καὶ τὸ ἀνὰ μέσον· ἐν ᾧ γὰρ τὰ ἄκρα, καὶ τὰ ἀνὰ μέσον, οἷον ἐπὶ λευκοῦ καὶ μέλανος· τὸ γὰρ χρῶμα γένος τούτων τε καὶ τῶν ἀνὰ μέσον χρωμάτων ἁπάντων.
Moreover, when there is no contrary to the genus, one must see not only if the contrary is in the same genus, but also the intermediate; for in whatever the extremes are, the intermediates also are, as in the case of white and black; for color is the genus of these and of all the intermediate colors.
Ἔνστασις ὅτι ἡ μὲν ἔνδεια καὶ ὑπερβολὴ ἐν τῷ αὐτῷ γένει (ἐν τῷ κακῷ γὰρ ἄμφω), τὸ δὲ μέτριον ἀνὰ μέσον ὂν τούτων οὐκ ἐν τῷ κακῷ ἀλλ᾿ ἐν τῷ ἀγαθῷ.
An objection is that deficiency and excess are in the same genus (for both are in the bad), but the moderate, being intermediate between these, is not in the bad but in the good.
Σκοπεῖν δὲ καὶ εἰ τὸ μὲν γένος ἐναντίον τινί, τὸ δὲ εἶδος μηδενί.
One must also examine whether the genus is contrary to something, but the species to nothing.
Εἰ γὰρ τὸ γένος ἐναντίον τινί, καὶ τὸ εἶδος, καθάπερ ἀρετὴ κακίᾳ καὶ δικαιοσύνη ἀδικίᾳ.
For if the genus is contrary to something, the species also is, as virtue to vice and justice to injustice.
Ὁμοίως δὲ καὶ ἐπὶ τῶν ἄλλων σκοποῦντι φανερὸν ἂν δόξειεν εἶναι τὸ τοιοῦτον.
Similarly also in other cases, such a thing would seem to be clear to one who examines.
Ἔνστασις ἐπὶ τῆς ὑγιείας καὶ νόσου· ἁπλῶς μὲν γὰρ πᾶσα ὑγίεια νόσῳ ἐναντίον, ἡ δέ τις νόσος εἶδος ὂν νόσου οὐδενὶ ἐναντίον, οἷον ὁ πυρετὸς καὶ ἡ ὀφθαλμία καὶ τῶν ἄλλων ἕκαστον.
An objection in the case of health and disease; for simply all health is contrary to disease, but a particular disease, which is a species of disease, is contrary to nothing, as fever and ophthalmia and each of the others.
Ἀναιροῦντι μὲν οὖν τοσαυταχῶς ἐπισκεπτέον· εἰ γὰρ μὴ ὑπάρχει τὰ εἰρημένα, δῆλον ὅτι οὐ γένος τὸ ἀποδοθέν· κατασκευάζοντι δὲ τριχῶς, πρῶτον μὲν εἰ τὸ ἐναντίον τῷ εἴδει ἐν τῷ εἰρημένῳ γένει, μὴ ὄντος ἐναντίου τῷ γένει· εἰ γὰρ τὸ ἐναντίον ἐν τούτῳ, δῆλον ὅτι καὶ τὸ προκείμενον.
Thus, for one who refutes, he must examine in so many ways; for if the mentioned things do not obtain, it is clear that the assigned genus is not a genus; but for one who establishes, in three ways: first, if the contrary to the species is in the mentioned genus, when there is no contrary to the genus; for if the contrary is in this, it is clear that the proposed species also is.
Ἔτι εἰ τὸ ἀνὰ μέσον ἐν τῷ εἰρημένῳ γένει· ἐν ᾧ γὰρ τὸ ἀνὰ μέσον, καὶ τὰ ἄκρα.
Moreover, if the intermediate is in the mentioned genus; for in whatever the intermediate is, the extremes also are.
Πάλιν ἂν ᾖ ἐναντίον τι τῷ γένει, σκοπεῖν εἰ καὶ τὸ ἐναντίον ἐν τῷ ἐναντίῳ· ἂν γὰρ ᾖ, δῆλον ὅτι καὶ τὸ προκείμενον ἐν τῷ προκειμένῳ.
Again, if there is any contrary to the genus, one must see if the contrary is also in the contrary; for if it is, it is clear that the proposed species is also in the proposed genus.
Πάλιν ἐπὶ τῶν πτώσεων καὶ ἐπὶ τῶν συστοίχων, εἰ ὁμοίως ἀκολουθοῦσι, καὶ ἀναιροῦντι καὶ κατασκευάζοντι.
Again, in the case of inflections and coordinates, one must see if they follow similarly, both for one who refutes and for one who establishes.
Ἅμα γὰρ ἑνὶ καὶ πᾶσιν ὑπάρχει ἢ οὐχ ὑπάρχει, οἷον εἰ ἡ δικαιοσύνη ἐπιστήμη τις, καὶ τὸ δικαίως ἐπιστημόνως καὶ ὁ δίκαιος ἐπιστήμων· εἰ δὲ τούτων τι μή, οὐδὲ τῶν λοιπῶν οὐδέν.
For they belong or do not belong to one and to all at the same time, as, for example, if justice is a certain knowledge, "justly" is also "knowingly" and the "just man" is "knowing"; but if any of these is not so, neither is any of the rest.