ἔγνω δὲ φώρ τε φῶρα καὶ λύκος λύκον → the thief knows the thief and the wolf knows the wolf, and thief knows thief and wolf his fellow wolf, set a thief to catch a thief
Δάω only in aor. pass. 1 know δᾰέντι δὲ καὶ σοφία μείζων ἄδολος τελέθει (O. 7.53) εὐθυπορεῖ, σάφα δᾰεὶς ἅ τε οἱ πατέρων ὀρθαὶ φρένες ἐξ ἀγαθῶν ἔχρεον (O. 7.91) ἀνδροδάμαντα δἐπεὶ Φῆρες δᾰεν ῥιπὰν μελιαδέος οἴνου fr. 166. 1.