τὸ κακὸν δοκεῖν ποτ' ἐσθλὸν τῷδ' ἔμμεν' ὅτῳ φρένας θεὸς ἄγει πρὸς ἄταν → evil appears as good to him whose mind the god is leading to destruction (Sophocles, Antigone 622f.)
adj.
Credulous: P. εὐεξαπάτητος.
Simple: P. and V. εὐήθης; see also guileless.