PlatonisCiceronis

“. . . no speech of admonition can be so fine that it will all at once make those who hear it good men if they are not good already; it would surely not make archers good if they had not had previous practice in shooting; neither would it make lancers good, nor horsemen; it cannot even make men able to endure bodily labour, unless they have been trained to it before.”
― Xenophon, Cyropaedia, Volume 1, books 1-4

“Well, when do we act like sheep: when we act for the sake of the belly, or of our sex-organs, or at random, or in a filthy fashion, or without due consideration, to what level have we degenerated?

To the level of sheep.”
― Epictetus, Epictetus. The Discourses as Reported By Arrian. Vol. I. Books 1 and 2. With an English Translation By W. A. Oldfather

“For moral excellence is concerned with pleasures and pains; it is on account of pleasure that we do bad things, and on account of pain that we abstain from noble ones. Hence we ought to have been brought up in a particular way from our very youth, as Plato says, so as both to delight in and to be pained by the things that we ought; for this is the right education.”
― Aristotle, Nicomachean Ethics

“Happiness, therefore, does not lie in amusement; it would, indeed, be strange if the end were amusement, and one were to take trouble and suffer hardship all one's life in order to amuse oneself. For, in a word, everything that we choose we choose for the sake of something else, except happiness, which is an end. Now to exert oneself and work for the sake of amusement seems silly and utterly childish. But to amuse oneself in order that one may exert oneself, as Anacharsis puts it, seems right; for amusement is a sort of relaxation, and we need relaxation because we cannot work continuously. Relaxation, then, is not an end; for it is taken for the sake of activity.”
― Aristotle, Nicomachean Ethics