This classmate told me that Plato drove this idea home in his dialogue Euthydemus, in which Socrates puts down the Sophists, claiming that a man learns more by "playing" with ideas in his leisure time that by sitting in a classroom. And Plato's successor, that world champion of pleasure, Epicurus, believed in a simple yet elegant connection between learning and happiness: the entire purpose of education was to attune the mind and sense to the pleasures of life.
