Theodoret, Letter 62 (tr. Blomfield Jackson):
A saying of one of the men who used to be called wise was, Live unseen. I applaud the sentiment, and have determined to confirm the word by deed, for I see no impropriety in gathering what is good from others, just as bees, it is said, gather their honey and draw forth the sweet dew from bitter herbs as well as from them that are good to eat, and I myself have seen them settling on a barren rock and sucking up its scanty moisture. Far more reasonable is it for them that are credited with reason to harvest what is good from every source; so, as I said, I try to live unseen, and above all men am I a lover of peace and quiet.
The Greek, slightly modified from Patrologia Graeca
vol. 83, col. 1233 A-B:
τὸ 'λάθε βιώσας' εἴρηκε μέν τις τῶν πάλαι καλουμένων σοφῶν, ἐγὼ δὲ τὴν γνώμην ἐπαινέσας ἐβουλήθην ἔργῳ βεβαιῶσαι τὸν λόγον. οὐδὲν γὰρ ἀπεικὸς ᾠήθην ποιεῖν καὶ παρὰ τῶν ἄλλων συλλέγων τὸ χρήσιμον. καὶ γὰρ τὰς μελίττας φασὶν οὐκ ἀπὸ τῶν ἐδωδίμων μόνον, ἀλλὰ καὶ ἀπὸ τῶν πικρῶν βοτανῶν, καὶ τὰ κηρία συλλέγειν καὶ τὴν γλυκεῖαν δρόσον ἀρύεσθαι.
εἶδον δὲ ἔγωγε καὶ πέτραις ἀγόνοις ἐνιζανούσας καὶ τὴν νοτίδα τὴν ὀλίγην ἀνιμωμένας. πολλῷ δὲ δήπουθεν δικαιότερον τοὺς τῷ λόγῳ τετιμημένους πάντοθεν καρποῦσθαι τὴν ὠφέλειαν. ἐγὼ μὲν οὖν, ὡς ἔφην, πειρῶμαι λανθάνειν καὶ πάντων μάλιστα τὴν ἡσυχίαν ἀσπάζομαι.
"One of the men who used to be called wise" — this is of course a reference to Epicurus, and the quotation (λάθε βιώσας
= live unknown) is fragment 551 in Usener's Epicurea