"My friend, Theodoros appears to have hit the mark  concerning your nature. For wonder is certainly the passion of a philosopher; for there is not another beginning of philosophy than this one, and the one who said that Iris  was born of Thaumas seems not to genealogize badly." -- Plato, Theaetetus
(Θεόδωρος γάρ͵ ὦ φίλε͵ φαίνεται οὐ κακῶς τοπάζειν περὶ τῆς φύσεώς σου. μάλα γὰρ φιλοσόφου τοῦτο τὸ πάθος͵ τὸ θαυμάζειν· οὐ γὰρ ἄλλη ἀρχὴ φιλοσοφίας ἢ αὕτη͵ καὶ ἔοικεν ὁ τὴν Ἶριν Θαύμαντος ἔκγονον φήσας οὐ κακῶς γενεαλογεῖν.) (Greek text from here. Another English translation - Fowler's 1921 translation - here at Perseus.)
 See his Metaphysics, 982b12.
 Literally, "not to aim badly."
 Plato associates Iris with speech or dialectic, or with the kind of conversation that leads to discovery.