μαχανά

κακοὶ μάρτυρες ἀνθρώποισιν ὀφθαλμοὶ καὶ ὦτα βαρβάρους ψυχὰς ἐχόντων → eyes and ears are poor witnesses for men if their souls do not understand the language (Heraclitus Phil.: Fr. B 107; Testimonia: Fragment 16, line 6)