Rules for psilosis (smoothing) and dasynesis (roughening) of initial α and ε before various consonants in Homeric Greek, with examples and exceptions.
Τὸ 'α' πρὸ τοῦ 'τ' ἑνὸς ἢ διττοῦ ψιλοῦται πλὴν τοῦ ἅτε καὶ ἅτερος. Τὸ 'α' πρὸ δασέος ψιλοῦται. σεσημείωται τὸ ἁφή καὶ τὰ παρ´ αὐτοῦ. Τὸ 'ε' κατὰ τοὺς παρῳχημένους προερχόμενον καὶ ἀποπῖπτον ψιλοῦται, ἔλεγον λέγον, ἔστην στῆν «ἔσταν ἅπαντες» (Α 535), ἐπεὶ γίνεται «στὰν δὲ μεταστοιχεί» (Il. Ψ 328), ἔστησα, ἐπεὶ «στῆσε δ´ ἐν Ἀμνισῷ ποταμῷ» (Od. τ 188), τὸ δὲ «ἕστασαν» (Β 777), δασύνεται, ἐπειδήπερ τὸ αὐτὸ ἐστὶ τῷ ἑστήκεσαν, τὸ δὲ 'ε' τοῦ παρακειμένου καὶ ὑπερσυντελίκου ἐπὶ τούτου τοῦ ῥήματος δασύνεται. τὸ δὲ ἑήνδανε καὶ ἑώρων, ἑέσσατο (Il. Κ 177) οὐκ ἐκ κλίσεως, ἀλλ´ ἐκ πλεονασμοῦ. Τὸ ἐν ἀντωνυμίαις 'ε' πρὸ συμφώνου ψιλοῦται, ἐμοί, ἐκεῖνος, πλὴν τοῦ ἕθεν. Τὸ 'ε' τῶν ἀριθμῶν δασύνεται, ἕν, ἕξ, ἑπτά καὶ τὰ λοιπὰ πλὴν τοῦ ἐννέα καὶ ἐννενήκοντα. καὶ καθόλου εἰπεῖν, πᾶς ἀριθμὸς ἀπὸ φωνήεντος ἀρχόμενος δασύνεται. * Τὸ 'ε' πρὸ τοῦ 'θ' οὐ δασύνεται, ἔθων (Ι 540), καθότι ἐδιδασκόμεθα καὶ ἐκ τῆς συναλοιφῆς «ἥ ἑ μάλιστ´ εἴωθε» (Ε 766), εἰ μὴ εἴη ἀντωνυμικὸν ἐξ ἀποβολῆς τοῦ 'σ', σέθεν ἕθεν. * Τὸ 'ε' πρὸ τοῦ 'κ' δασύνεται μὴ ὂν ἐκ κλίσεως ὡς ἐκάλουν, ἔκρινον, ἢ προθέσεως ὡς ἔκπωμα, ἐκτός ἢ μεμελετηκὸς ἀφαιρεῖσθαι, ὡς ἐκεῖνος, οἷον, ἑκάς, Ἑκάβη, ἕκηλος, ἑκυρός, ἕκαστος. μάχεται τὸ ἐκεχειρία, ὅπερ οὐκ ἔχει γνήσιον τὸ 'κ', ἀπὸ τοῦ ἔχειν γενόμενον. Τὸ 'ε' ἐπιφερομένου τοῦ 'μ' ἢ κατὰ σύλληψιν ἢ κατὰ διάστασιν ψιλοῦσθαι θέλει, ἔμπλην, Ἔμπουσσα. * Τὸ 'ε' πρὸ τοῦ ἑνὸς 'ν' ψιλοῦσθαι θέλει οἷον Ἐνυώ, ἔνδιοι,
The ‘α’ before ‘τ’, single or double, is unaspirated, except in ἅτε and ἅτερος. The ‘α’ before an aspirate is unaspirated; ἁφή and the forms derived from it are noted as exceptions. The ‘ε’, when it comes from the past tenses and drops out, is unaspirated: ἔλεγον (from) λέγον, ἔστην (from) στῆν, “ἔσταν ἅπαντες” (Α 535), since it becomes “στὰν δὲ μεταστοιχεῖ” (Il. Ψ 328); ἔστησα, since “στῆσε δ´ ἐν Ἀμνισῷ ποταμῷ” (Od. τ 188). But “ἕστασαν” (Β 777) is aspirated, since it is the same as ἑστήκεσαν; and the ‘ε’ of the perfect and pluperfect in the case of this verb is aspirated. But ἑήνδανε and ἑώρων, ἑέσσατο (Il. Κ 177) are not from inflection, but from pleonasm. The ‘ε’ in pronouns before a consonant is unaspirated: ἐμοί, ἐκεῖνος, except ἕθεν. The ‘ε’ of the numerals is aspirated: ἕν, ἕξ, ἑπτά, and the rest, except ἐννέα and ἐννενήκοντα; and, generally speaking, every numeral beginning with a vowel is aspirated. The ‘ε’ before ‘θ’ is not aspirated: ἔθων (Ι 540), as we were taught also from the contraction “ἥ ἑ μάλιστ´ εἴωθε” (Ε 766), unless it is pronominal from loss of ‘σ’, σέθεν, ἕθεν. The ‘ε’ before ‘κ’ is aspirated when it is not from inflection, as in ἐκάλουν, ἔκρινον, or from a preposition, as in ἔκπωμα, except where it has been practiced to be taken away, as in ἐκεῖνος; for example, ἑκάς, Ἑκάβη, ἕκηλος, ἑκυρός, ἕκαστος. ἐκεχειρία is at variance, since it does not have a genuine ‘κ’, having arisen from ἔχειν. The ‘ε’ when ‘μ’ follows, whether by combination or by separation, tends to be unaspirated: ἔμπλην, Ἔμπουσσα. The ‘ε’ before a single ‘ν’ tends to be unaspirated, for example Ἐνυώ, ἔνδιοι.