ἰσχυριστέον
From LSJ
κράτιστοι δ᾽ ἂν τὴν ψυχὴν δικαίως κριθεῖεν οἱ τά τε δεινὰ καὶ ἡδέα σαφέστατα γιγνώσκοντες καὶ διὰ ταῦτα μὴ ἀποτρεπόμενοι ἐκ τῶν κινδύνων → the bravest are surely those who have the clearest vision of what is before them, glory and danger alike, and yet notwithstanding, go out to meet it | and they are most rightly reputed valiant who, though they perfectly apprehend both what is dangerous and what is easy, are never the more thereby diverted from adventuring
English (LSJ)
one must maintain stoutly, Pl.R.533a.
Greek (Liddell-Scott)
ἰσχῡριστέον: ῥημ. ἐπίθ. τοῦ ἰσχυρίζομαι, δεῖ ἰσχυρίζεσθαι, Πλάτ. Πολ. 533Α.
Greek Monotonic
ἰσχῡριστέον: ρημ. επίθ., αυτό για το οποίο κανείς πρέπει να δείξει επιμονή, σε Πλάτ.