The Dual

173. The dual is chiefly used (1) of two objects thought of as a distinct pair, and (2) when the numeral δύω is used.

1. Thus we have the natural pairs χεῖρε, πήχεε, τένοντε, ὤμω, μηρώ, ὄσσε, ὀφθαλμώ, and (in the genitive and dative) ποδοῖϊν, βλεφάροιϊν
   

   σταθμώ
   door posts

   ἵππω
   the horses of a chariot

   βόε
   a yoke of oxen

   ἄρνε
   a pair of lambs
   (for sacrifice)

   δοῦρε (in Il. 13.241, 16.139 of the two spears usually carried, but δύο δοῦρε is more common); ποταμώ (Il. 5.773) of the twο rivers of the Troad, and so κρουνώ (Il. 22.147). So of the twο warriors in a chariot (Il. 5.244, 272, 568), two wrestlers (Il. 23.707), twο dancers (Od. 8.378), the Sirens (Od. 12.52, etc.); the Ἀτρείδα and Αἴαντε.

   The numeral is generally added in speaking of two wild animals (θῆρε δύω, λέοντε δύω, etc.); κάπρω (Il. 11.324) and λέοντε (Il. 16.756) are hardly exceptions, since the context shows that two are meant. Also αἰετώ (Od. 2.146) of two eagles sent as an omen, and γῦπε (Od. 11.578) of the vultures that devoured Tityοs.

   The dual in Il. 8.185-191 (where Hector calls to four horses by name) might be defended, because twο is the regular number; but probably v. 185 is spurious. In Il. 23.413, again—αἴ κʼ ἀποκηδήσαντε φερώμεθα χεῖρον ἄεθλον—the dual is used because it is the horses that are chiefly in the driverʼs mind, although he associates himself with them. In Il. 9.182-195 the dual refers to the two envoys, Phoenix being overlooked.

   Again, when two agents have been mentioned together, or are represented as acting together in any way, the dual may be used.

   Il. 1.531 τώ γʼ ὢς βουλεύσαντε
   (of Thetis and Achilles)

   Il. 16.823 (of a lion and boar fighting), Od. 3.128, 13.372, etc. Similarly, of the meeting of twο rivers.

   Il. 4.453 ἐς μισγάγκειαν συμβάλλετον ὄβριμον ὕδωρ (cp. 5.774)

   The dual pronouns νῶϊ and σφῶϊ are used with comparative regularity; see Il. 1.257, 336, 574; 5.34, 287, 718, etc. This usage may be a matter of traditional courtesy. Hence perhaps the scrupulous use where the 1st person dual is meant.

   Il. 4.407 ἀγαγόνθʼ
                ("Diοmede and I")

   Il. 8. 109 θεράποντε
                    or attendants

   Il. 11.313 τί παθόντε λελάσμεθα κτλ.

   Il. 12.323 ὦ πέπον εἰ . . . φυγόντε

   Od. 3. 128 ἕνα θυμὸν ἔχοντε
                     ("Ulysses and I")

   In Od. 2.78 for ἀπαιτίζοντες ἕως should be read ἀπαιτίζονθʼ ἧος, since Telemachus there is speaking of his mother and himself. So with the 2nd person, Il. 1.216 (Athene and Here), 322 (the heralds), 3.279, 7.279.

   In Il. 3.278

   καὶ οἳ ὑπένερθε καμόντας ἀνθρώπους τίνυσθον, ὅτις κʼ ἐπίορκον ὀμόσσῃ

   the two gods indicated by the dual are doubtless Hades and Persephone, as appears from ll. 9.456

   θεοὶ δʼ ἐτέλειον ἐπαράς, Σεύς τε καταχθόνιος καὶ ἐπαινὴ Περσεφόνεια

   and 9.559, where Althaea beats upon the earth κικλήσκουσʼ Ἀΐδην καὶ ἐπαινὴν Περσεφόνειαν. And since these were the gods especially called upon as witnesses and avengers of wrong, it is probable that they are meant in Od. 1.273 θεοὶ δʼ ἐπιμάρτυροι ἕστων. The omission of the names may be a mark of reverence. If this view is correct, it removes the difficulty as to ἔστων (Meyer, G. G. § 577, 1).

2. Of the use with the numeral the most significant examples are Od. 8.35, 48
   

   κούρω δὲ κρινθέντε δύω καὶ πεντήκοντα βήτην

   where the dual is used by a kind of attraction to the sword δύω.

   The dual is never obligatory in Homer, since the plural may always be used instead of it. Hence we often have a dual noun or pronoun with a plural verb or adjective, and νice νersa.

   The neuter dual (like the neuter plural) may go with a singular verb; thus we have ὄσσε with all three numbers.

   Certain of the ancient grammarians—Zenodotus among them—supposed that Homer sometimes used the dual for the plural. But Aristarchus showed that in all the passages on which this belief was founded the dual either had its proper force, or was a false reading.

   The use of the dual in Attic is nearly the same as in Homer, in other dialects it appears to have become obsolete. This was one of the reasons that led some grammarians to maintain that Homer was an Athenian.

   Note— For the use of the dual with a large number which contains the numeral δύο cp. πεντακοσίαις εἴκοσι δυοῖν δραχμαῖν in an Attic inscription of the 5th century (Meisterhans, p. 45, 4). This is a good parallel to

   Od. 8.35 & 48 κούρω δύω καὶ πεντήκοντα