Epicurus, fragment 187 Usener:
I never desired to please the crowd. For the things which pleased them, I did not learn; and the things which I knew, were far from their perception.
οὐδέποτε ὠρέχθην τοῖς πολλοῖς ἀρέσκειν. ἅ μέν γάρ ἐκείνοις ἤρεσκεν, οὐκ ἔμαθον· ἅ δ᾿ ᾔδειν ἐγώ, μακράν ἦν τῆς ἐκείνων αἰσθήσεως.
Seneca, Letters to Lucilius
29.10, renders this as follows:
I never wanted to please the crowd; for the things which I know, the crowd does not approve, and the things which the crowd approves, I do not know.
numquam volui populo placere; nam quae ego scio non probat populus, quae probat populus ego nescio.