In fact, the connection between good manners and good citizenship has been a concern to political philosophers at least as far back as the fourth century B.C., when Aristotle argued that a dignified and respectful affection, philia, should naturally prevail among fellow citizens of any virtuous state. Because it’s based on the assumption of a certain degree of common interests and goals, such affection, the philosopher went on to suggest, was more important in democracies than in tyrannies. A few hundred years later, the Roman statesman Cicero wrote a treatise called De Re Publica, “On the Republic,” in which he argued for the importance of humanitas, the communal fellow-feeling that should act as a natural brake on individual selfishness and the impulse to advance only our purely private interests.
Source: Daniel Mendelsohn, Is This the End of Civility As We Know It? – Modern Etiquette