μετὰ μαινομένων μαίνεσθαί ϕασι καλόν.

To rage amidst the raging is said to be beautiful?

Sorry about this deluge of questions but there’s no answer key for these extra exercises.

I interpret it as

amidst the raging, they say raging is beautiful.

They say that among crazies, to be crazy is something admirable.

This stands out among your iambic trimeters because it’s not an iambic trimeter. It starts out looking like an anapestic dimeter but then turns to prose. In fact it seems to be a cut-down version of a catalectic anapestic tetrameter, a verse much used by early comic poets but hardly at all in tragedy. The verse in its entirety goes
μετὰ μαινoμένων φασὶν χρῆναι
μαίνεσθαι πάντας ὁμοίως.
(“Among crazies they say everyone should be equally crazy”)

If it were prose you’d. expect μετὰ τῶν μαινομένων, with article.

That’s interesting, it sounds like emperor’s new clothes topos. Everybody has to accept some crazy ideology, so a lucid non-conformist is very dangerous. Speaking of which, Socrates is constantly talking about the gods (at least according to Plato) but he couldn’t possibly have believed in them, could he?