ὅστις ἀγνοεῖ, “that he really does not see,” admitting the possibility more than would ὥστε ἀγνοεῖν.
εἰ τοῦτο γενήσεται, “if this does happen.” The “monitory” form of future protasis.
ἐπὶ τοῖς μεγάλοις τόκοις. ἐπί of the conditions, after δανειζόμενοι. So ἐπὶ πολλῷ, below. The article is unsatisfactory.
τῶν ἀρχαίων, “their original property.”
ἀπέστησαν, gnomic aorist.
ὧν=τούτων ἅ, partitive gen. after πολλά: but the insertion of καὶ χαλεπὰ is awkward.
εἰς ἀνάγκην ἔλθωμεν. With infin., for ἀναγκασθῶμεν.