Argument: If Ἐλπίς is understood as “presentiment [of the κακῶν]”, not “hope/Hope” in Hesiod Works and Days 97, the understanding would motivate lines 103-4 and the “σιγῇ”.
Hesiod Works and Days 94-105
ἀλλὰ γυνὴ χείρεσσι πίθου μέγα πῶμ᾽ ἀφελοῦσα
ἐσκέδασ᾽: ἀνθρώποισι δ᾽ ἐμήσατο κήδεα λυγρά.
μούνη δ᾽ αὐτόθι Ἐλπὶς ἐν ἀρρήκτοισι δόμοισιν
ἔνδον ἔμιμνε πίθου ὑπὸ χείλεσιν, οὐδὲ θύραζε
ἐξέπτη: πρόσθεν γὰρ ἐπέλλαβε πῶμα πίθοιο
αἰγιόχου βουλῇσι Διὸς νεφεληγερέταο.
ἄλλα δὲ μυρία λυγρὰ κατ᾽ ἀνθρώπους ἀλάληται:
πλείη μὲν γὰρ γαῖα κακῶν, πλείη δὲ θάλασσα:
νοῦσοι δ᾽ ἀνθρώποισιν ἐφ᾽ ἡμέρῃ, αἳ δ᾽ ἐπὶ νυκτὶ
αὐτόματοι φοιτῶσι κακὰ θνητοῖσι φέρουσαι
σιγῇ, ἐπεὶ φωνὴν ἐξείλετο μητίετα Ζεύς.
οὕτως οὔτι πη ἔστι Διὸς νόον ἐξαλέασθαι.
In West’s commentary to this line, he writes “Ἐλπίς is expectation, usually of good things, though it (and more frequently ἐλπίζω) can also be used of bad. Unqualified, it will naturally have the first sense: (expectant) Hope.”
West goes on to discuss the various problems that exist with the story as told, that hope exists among men, that the jar is apparently one of ills, not mixed, and suggests that the Babrius version of the story (where the jar of good things is opened, only Hope remaining to mankind) was something like the underlying story which Hesiod is here modifying, with inconsistent results.
Opera et dies Schol. vet. 97
ἔνδον ἔμιμνε πίθου: πῶς, φησιν, ἔμεινεν ἐν τῷ πίθῳ; ἐλπὶς γάρ ἐστιν ἐν ἀνθρώποις· τοῦτο δὲ καὶ Κώμανος ὁ ἀρχιοινοχόος τοῦ βασιλέως προὔτεινε. φησὶν οὖν Ἀρίσταρχος (frg. 6 Waeschke) ὅτι ἡ μὲν τῶν κακῶν ἔμεινεν ἡ δὲ τῶν ἀγαθῶν ἐξῆλθεν· ὅθεν ἀκυρολογοῦμεν λέγοντες ὅτι ἐλπίζειν κακά ἐστι λέγειν ἐπὶ ἀγαθῶν. ἡ γὰρ ἐλπὶς οὐχ ὑπὸ κακῶν, ἀλλ’ ὑπ’ ἀγαθῶν ἢ ἀλλ’ ὑπὸ θεῶν. ὁ δὲ Ἡσίοδος ἀκύρως ἐπὶ κακῶν εἶπε· μούνη δ’ αὐτόθι Ἐλπίς.
Aristarchus’ says that this is ἐλπίς τῶν κακῶν. Ignoring the unnecessary “ἡ δὲ τῶν ἀγαθῶν ἐξῆλθεν…” and the fatuous discussion afterwards, notice how ἐλπίς τῶν κακῶν motivates lines 103-4:
αὐτόματοι φοιτῶσι κακὰ θνητοῖσι φέρουσαι
σιγῇ, ἐπεὶ φωνὴν ἐξείλετο μητίετα Ζεύς.
(West reads αὐτόμαται)
In the normal reading of ἐλπίς as hope, these lines come from nowhere, simply adding color. Where has Zeus actually done this in the above? It seems like an extraneous action on his part in regards to the story. A poetical fumble.
And φωνή needs to be explained. West gives the theory that since they would hardly need sound-proofing they therefore need voices in order to be made silent. !!
However, if ἐλπίς is expectation or presentiment of evil, then the motivation of the lines perfectly clear: Zeus has taken away the the announcement of the coming of evil things by taking away the ἐλπίς/expectation of their arrival. φωνή τῶν νουσῶν is an alternation of ἐλπίς τῶν νουσῶν. This alteration also fixes the other problems of the story that West listed: ἐλπὶς τῶν κακῶν is not present among men and is easy to understand as an evil along with other evils.
What about the argument that bare ἐλπίς is difficult to read as anything but hope? I think that this may be anachronistic. Contra-West, unlike the Athenian usage where ἐλπίς parallels ἐλπίζω, for Hesiod ἔλπομαι was the verb closest to ἐλπίς. In Herodotus, who uses both ἔλπομαι and ἐλπίζω, ἔλπεσθαι is always “to think likely, to suppose”, and never “to hope”. Of the noun, there are very few early examples. One or two in Homer (ε84 ἢ Ὀδυσεὺς ἔλθῃ· ἔτι γὰρ καὶ ἐλπίδος αἶσα, actually a threat to Melantho, π101 is bracketed). In Hesiod, the other place that it occurs is lines 498-502:
πολλὰ δ’ ἀεργὸς ἀνήρ, κενεὴν ἐπὶ ἐλπίδα μίμνων,
χρηίζων βιότοιο, κακὰ προσελέξατο θυμῷ.
ἐλπὶς δ’ οὐκ ἀγαθὴ κεχρημένον ἄνδρα κομίζει,
ἥμενον ἐν λέσχῃ, τῷ μὴ βίος ἄρκιος εἴη.
This is closer to “hope”, but there’s nothing that precludes something less relentlessly positive than the English idea of hope – for example “hunch”.
Given the known range of ἔλπoμαι, a tightening of the idea of ἐλπίς over the centuries seems possible.