Verb – Accusative subject infinitives

Δεῖ itself may also be past in the Eluon form, as in ἔδει where the necessity of doing the event occurred before the time of speaking:

The obligation to sacrifice is in the past relative to the narrator’s time. This also serves as an example where there is no explicit subject given for δεῖ. When used without a subject, δεῖ refers to a general obligation for a group rather than a particular individual.

The second syntactic environment where we find accusative subjects is in infinitive clauses after some verbs. For example, the verb ἐρωτᾷ can take an infinitive complement, and this infinitive complement takes an accusative subject:

The pronoun αὐτόν serves as the subject of the subordinate infinitive μεῖναι. However, αὐτόν also serves as the object of ἠρώτων, so it seems to be playing a syntactic role in both the main clause and the infinitive clause simultaneously, though those roles are different.

We can harmonize these two syntactic environments in which we find accusative subjects of infinitives. The word δεῖ literally means to bind, and the verb still has that meaning at times. Although it looks like the subject of δεῖ is the accusative, we could also analyze it as the object of δεῖ and as the subject of the infinitive just like ἐρωτᾷ. The true subject of δεῖ would then be an impersonal subject that has bound or obligated someone to do something else. This allows us to make a very simple statement: infinitives take accusative subjects, and some verbs that select for an infinitive complement, like ἐρωτᾷ, may also have an accusative object that has a dual function of both subject of the infinitive and object of the main verb.