And be silent for the most part, or else make only the most necessary remarks, and express these in few words. But rarely, and when occasion requires you to talk, talk, indeed, but about no ordinary topics. Do not talk about gladiators, or horseraces, or athletes, or things to eat or drink - topics that arise on all occasions; but above all, do not talk about people, either blaming, or praising, or comparing them.
Epictetus (1925). “The Discourses as reported by Arrian: the Manual, and fragments”