Trial translation:
For I have this thought; for the purpose of helping this man, even with another man to talk about him I consider gross impiety, but for inflicting punishment [discussing this] with himself [is] a hallowed and sacred [act].
I am guessing that the reader is meant to fill out this phrase “καὶ πρὸς αὐτὸν τοῦτον”.
“πρὸς αὐτὸν” = “with Eratosthenes, the accused, himself”
“touton” = “to talk with”
Or more loosely, something like this: although I would be defiled if I talked with anybody else to help Eratosthenes, to interrogate him in order to punish him is holy work.
I read καί as just an “and” between that ἐπί and πρός, not “even”. It also gets repeated in the second bit
I don’t think διαλέγεσθαι takes interrogate as a primary meaning, though it could be the implication.
ὠφελείᾳ/βλάβῃ contrast is more like advantage/disadvantage or gain/injury
For me anyway, it comes out this:
I hold this sort of opinion: I consider it to be irreligious to discuss him with another for his advantage, but with him, and for his harm, pious and religious.
The odd bit to me is that I’d like to read ἐπὶ τῇ τούτου ὠφελείᾳ as what he would consider the result of such a discussion, not its purpose. But as written, it goes with διαλέγεσθαι. Still, maybe its only real purpose is to balance the ἐπὶ τῇ τούτου βλάβῃ, which does have clear meaning.
It’s a typically clear-cut twofold opposition, first between ἐπὶ μὲν τῇ τούτου ὠφελείᾳ and ἐπὶ δὲ τῇ τούτου βλάβῃ, then between πρὸς ἕτερον περὶ τούτου and πρὸς αὐτὸν τοῦτον. “I consider that if it’s to his benefit even to talk to some else about him is ἀσεβές but if it’s to his harm even to talk directly to him is ὅσιον καὶ εὐσεβές.” (Each καί is “even.”)
I was looking for the antecedents of “πρὸς αὐτὸν τοῦτον” and even more basically for a good meaning of “πρὸς” in context, and had not yet confronted most of the issues raised in the comments of Joel and Michael. But at least I’ve reached a point where, to my advantage, I can understand their comments.
I remember years ago struggling with antecedents of French relative pronouns in the long sentences of Proust. Thanks to going through the work twice, with the aid of Scott Moncrieff, the antecedents began to seem intuitive. “It takes a heap” of practice to make pronouns more clear.
Yes here we have τουτου three times and τουτον once—all meaning Eratosthenes, whose presence we are to imagine. To say “this man” would be too heavy in English but the repetition is effective in Lysias’ Greek. πρὸς αὐτὸν τοῦτον is literally “to this man himself” or “in person” (my “directly to him”), and διαλέγεσθαι introduces the Q&A form of the prosecutorial interrogation.
