§8.12Λόγος δ᾿ ἐστὶ δῆλος ἕνα μὲν τρόπον καὶ δημοσιώτατον, ἐὰν ᾖ συμπεπερασμένος οὕτως ὥστε μηδὲν δεῖν ἐπερωτῆσαι· ἕνα δέ, καὶ ὃς μάλιστα λέγεται, ὅταν εἰλημμένα μὲν ᾖ ἐξ ὧν ἀναγκαῖον εἶναι, ᾖ δὲ διὰ συμπερασμάτων συμπεραινόμενα· ἔτι εἰ ἐλλείπει σφόδρα ἐνδόξων.
An argument is clear, in one way and the most common, if it has been concluded in such a way that there is no need to ask anything further; in another way, and the one most commonly spoken of, when premises have been assumed from which it is necessary for the conclusion to follow, and these are concluded through intermediate conclusions; further, if it is lacking in premises that are highly accepted.
Ψευδὴς δὲ λόγος καλεῖται τετραχῶς, ἕνα μὲν τρόπον ὅταν φαίνηται συμπεραίνεσθαι μὴ συμπεραινόμενος, ὃς καλεῖται ἐριστικὸς συλλογισμός· ἄλλον δὲ ὅταν συμπεραίνηται μὲν μὴ μέντοι πρὸς τὸ προκείμενον, ὅπερ συμβαίνει μάλιστα τοῖς εἰς τὸ ἀδύνατον ἄγουσιν· ἢ πρὸς τὸ προκείμενον μὲν συμπεραίνηται, μὴ μέντοι κατὰ τὴν οἰκείαν μέθοδον.
An argument is called false in four ways: in one way, when it seems to be concluded but is not concluded, which is called an eristic deduction; in another way, when it is concluded but not to the proposed issue, which happens most of all to those who lead to the impossible; or if it is concluded to the proposed issue, but not according to the appropriate method.
Τοῦτο δ᾿ ἐστίν, ὅταν μὴ ὢν ἰατρικὸς δοκῇ ἰατρικὸς εἶναι ἢ γεωμετρικὸς μὴ ὢν γεωμετρικὸς ἢ διαλεκτικὸς μὴ ὢν διαλεκτικός, ἄν τε ψεῦδος ἄν τ᾿ ἀληθὲς ᾖ τὸ συμβαῖνον.
This is when, not being medical, it seems to be medical, or not being geometrical, it seems to be geometrical, or not being dialectical, it seems to be dialectical, whether the resulting conclusion is false or true.
Ἄλλον δὲ τρόπον ἐὰν διὰ ψευδῶν συμπεραίνηται.
In another way, if it is concluded through false premises.
Τούτου δ᾿ ἔσται ποτὲ μὲν τὸ συμπέρασμα ψεῦδος, ποτὲ δ᾿ ἀληθές· τὸ μὲν γὰρ ψεῦδος ἀεὶ διὰ ψευδῶν περαίνεται, τὸ δ᾿ ἀληθὲς ἐγχωρεῖ καὶ μὴ ἐξ ἀληθῶν, ὥσπερ εἴρηται καὶ πρότερον.
Of this, sometimes the conclusion will be false, and sometimes true; for a falsehood is always concluded through false premises, but a truth can be concluded also from premises that are not true, as was said before.
Τὸ μὲν οὖν ψευδῆ τὸν λόγον εἶναι τοῦ λέγοντος ἁμάρτημα μᾶλλον ἢ τοῦ λόγου, καὶ οὐδὲ τοῦ λέγοντος ἀεί, ἀλλ᾿ ὅταν λανθάνῃ αὐτόν, ἐπεὶ καθ᾿ αὐτόν γε πολλῶν ἀληθῶν ἀποδεχόμεθα μᾶλλον, ἂν ἐξ ὅτι μάλιστα δοκούντων ἀναιρῇ τι τῶν ἀληθῶν.
Therefore, for an argument to be false is a fault of the speaker rather than of the argument, and not always of the speaker, but only when it escapes his notice; since in itself we accept it more than many true arguments, if from premises that are as accepted as possible it refutes some truth.
Τοιοῦτος γὰρ ὢν ἑτέρων ἀληθῶν ἀπόδειξίς ἐστιν· δεῖ γὰρ τῶν κειμένων τι μὴ εἶναι παντελῶς, ὥστ᾿ ἔσται τούτου ἀπόδειξις.
For such an argument is a proof of other truths; for one of the laid down premises must not exist at all, so that it will be a proof of this.
Εἰ δ᾿ ἀληθὲς συμπεραίνοιτο διὰ ψευδῶν καὶ λίαν εὐηθῶν, πολλῶν ἂν εἴη χείρων ψεῦδος συλλογιζομένων· εἴη δ᾿ ἂν τοιοῦτος καὶ ψεῦδος συμπεραινόμενος.
But if a truth should be concluded through false and highly foolish premises, it would be worse than many arguments concluding a falsehood; and such an argument might also conclude a falsehood.
Ὥστε δῆλον ὅτι πρώτη μὲν ἐπίσκεψις λόγου καθ᾿ αὑτὸν εἰ συμπεραίνεται, δευτέρα δὲ πότερον ἀληθὲς ἢ ψεῦδος, τρίτη δ᾿ ἐκ ποίων τινῶν.
So it is clear that the first examination of an argument in itself is whether it is concluded, the second is whether it is true or false, and the third is from what kind of premises.
Εἰ μὲν γὰρ ἐκ ψευδῶν ἐνδόξων δέ, λογικός, εἰ δ᾿ ἐξ ὄντων μὲν ἀδόξων δέ, φαῦλος.
For if it is from premises that are false but accepted, it is logical; but if from premises that are true but contrary to accepted opinion, it is poor.
Εἰ δὲ καὶ ψευδῆ καὶ λίαν ἄδοξα, δῆλον ὅτι φαῦλος, ἢ ἁπλῶς ἢ τοῦ πράγματος.
And if they are both false and highly contrary to accepted opinion, it is clear that it is poor, either absolutely or in relation to the matter.
§8.13Τὸ δ᾿ ἐν ἀρχῇ καὶ τὰ ἐναντία πῶς αἰτεῖται ὁ ἐρωτῶν, κατ᾿ ἀλήθειαν μὲν ἐν τοῖς Ἀναλυτικοῖς εἴρηται, κατὰ δόξαν δὲ νῦν λεκτέον.
How the questioner asks for the point at the beginning and for contraries, in truth, has been told in the Analytics, but according to opinion must be told now.
Αἰτεῖσθαι δὲ φαίνονται τὸ ἐν ἀρχῇ πενταχῶς, φανερώτατα μὲν καὶ πρῶτον εἴ τις αὐτὸ τὸ δείκνυσθαι δέον αἰτήσει.
They seem to ask for the point at the beginning in five ways: most clearly and first, if someone should ask for the very thing that needs to be shown.
Τοῦτο δ᾿ ἐπ᾿ αὐτοῦ μὲν οὐ ῥᾴδιον λανθάνειν, ἐν δὲ τοῖς συνωνύμοις, καὶ ἐν ὅσοις τὸ ὄνομα καὶ ὁ λόγος τὸ αὐτὸ σημαίνει, μᾶλλον.
This is not easy to escape notice when it is by itself, but is more likely to do so in synonyms, and in those things where the name and the definition signify the same thing.
Δεύτερον δὲ ὅταν κατὰ μέρος δέον ἀποδεῖξαι καθόλου τις αἰτήσῃ, οἷον ἐπιχειρῶν ὅτι τῶν ἐναντίων μία ἐπιστήμη, ὅλως τῶν ἀντικειμένων ἀξιώσειε μίαν εἶναι· δοκεῖ γὰρ ὃ ἔδει καθ᾿ αὑτὸ δεῖξαι μετ᾿ ἄλλων αἰτεῖσθαι πλειόνων.
Second, when one needs to prove a point in part, but asks for it universally; for example, when attempting to show that there is one science of contraries, he should claim that there is one of opposites in general; for he seems to ask for what he ought to show by itself along with other more numerous things.
Τρίτον εἴ τις καθόλου δεῖξαι προκειμένου κατὰ μέρος αἰτήσειεν, οἷον εἰ πάντων τῶν ἐναντίων προκειμένου τῶνδέ τινων ἀξιώσειε· δοκεῖ γὰρ καὶ οὗτος, ὃ μετὰ πλειόνων ἔδει δεῖξαι, καθ᾿ αὑτὸ χωρὶς αἰτεῖσθαι.
Third, if someone, when it is proposed to show a point universally, should ask for it in part; for example, if, when it is proposed for all contraries, he should claim it for some specific ones; for this person also seems to ask by itself and separately for what he ought to have shown along with more numerous things.
Πάλιν εἴ τις διελὼν αἰτεῖται τὸ προβληθέν, οἷον εἰ δέον δεῖξαι τὴν ἰατρικὴν ὑγιεινοῦ καὶ νοσώδους, χωρὶς ἑκάτερον ἀξιώσειεν.
Again, if someone, having divided the proposed issue, asks for it; for example, if, when needing to show that medicine is of the healthy and of the diseased, he should claim each separately.
Ἢ εἴ τις τῶν ἑπομένων ἀλλήλοις ἐξ ἀνάγκης θάτερον αἰτήσειεν, οἷον τὴν πλευρὰν ἀσύμμετρον τῇ διαμέτρῳ, δέον ἀποδεῖξαι ὅτι ἡ διάμετρος τῇ πλευρᾷ.
Or if someone should ask for one of two things that follow from each other of necessity; for example, that the side is incommensurable with the diagonal, when needing to prove that the diagonal is incommensurable with the side.
Ἰσαχῶς δὲ καὶ τἀναντία αἰτοῦνται τῷ ἐξ ἀρχῆς.
In as many ways they also ask for the contrary of the point at the beginning.
Πρῶτον μὲν γὰρ εἴ τις τὰς ἀντικειμένας αἰτήσαιτο φάσιν καὶ ἀπόφασιν, δεύτερον δὲ τἀναντία κατὰ τὴν ἀντίθεσιν, οἷον ἀγαθὸν καὶ κακὸν ταὐτόν.
First, if someone should ask for the opposite affirmation and negation; second, the contraries according to the opposition, for example, that good and bad are the same.
Τρίτον εἴ τις τὸ καθόλου ἀξιώσας ἐπὶ μέρους αἰτοῖτο τὴν ἀντίφασιν, οἷον εἰ λαβὼν τῶν ἐναντίων μίαν ἐπιστήμην, ὑγιεινοῦ καὶ νοσώδους ἑτέραν ἀξιώσειεν, ἢ τοῦτο αἰτησάμενος ἐπὶ τοῦ καθόλου τὴν ἀντίθεσιν πειρῷτο λαμβάνειν.
Third, if someone, having claimed the universal, should ask for the contradiction in part; for example, if, having assumed that there is one science of contraries, he should claim that there is a different one of the healthy and of the diseased, or having asked for this, he should try to assume the opposition in the universal.
Πάλιν ἐάν τις αἰτήσῃ τὸ ἐναντίον τῷ ἐξ ἀνάγκης συμβαίνοντι διὰ τῶν κειμένων, κἂν εἴ τις αὐτὰ μὲν μὴ λάβοι τἀντικείμενα, τοιαῦτα δ᾿ αἰτήσαιτο δύο ἐξ ὧν ἔσται ἡ ἀντικειμένη ἀντίφασις.
Again, if someone asks for the contrary of what follows of necessity through the premises; or even if someone should not assume the opposites themselves, but should ask for two such premises from which the opposite contradiction will result.
Διαφέρει δὲ τὸ τἀναντία λαμβάνειν τοῦ ἐν ἀρχῇ ὅτι τοῦ μέν ἐστιν ἡ ἁμαρτία πρὸς τὸ συμπέρασμα (πρὸς γὰρ ἐκεῖνο βλέποντες τὸ ἐν ἀρχῇ λέγομεν αἰτεῖσθαι), τὰ δ᾿ ἐναντία ἐστὶν ἐν ταῖς προτάσεσι τῷ ἔχειν πως ταύτας πρὸς ἀλλήλας.
And asking for contraries differs from begging the question in that for the latter the error is in relation to the conclusion (for looking at that, we say that the point at the beginning is asked), but contraries are in the premises by those premises having a certain relation to each other.