"[From enemies the wise learn many things.] For caution saves everything. You would not learn this, then, from a friend, but the enemy himself compels [sc. you to know it]".[1] And Menander [writes]: "might we not be saved whence we are destroyed?"[2] From our enemies. For when we fear our enemies we are helped by them; and from our enemies we learn about watchfulness and foresight. "After all, cities learned from men [sc. who were] enemies, not friends, to build high walls and to possess long ships. This lesson saves children, home[s], goods".[3]