Letters from a Stoic

Are you really surprised, as if it were something unprecedented, that so long a tour and such diversity of scene have not enabled you to throw off this melancholy and this feeling of depression? A change of character, not a change of air, is what you need.
Letter XXVIII

I have been speaking about liberal studies. Yet look at the amount of useless and superfluous matter to be found in the philosophers. Even they have descended to the level of drawing distinctions between the uses of different syllables and discussing the proper meanings of prepositions and conjunctions. They have come to envy the philologist and the mathematician, and they have taken over all the inessential elements in those studies -- with the result that they know more about devoting care and attention to their speech than about devoting such attention to their lives. Letter LXXXVIII