In stark contrast to the animals of fable, comedy and belles-lettres, can range the established canon of monsters which appear throughout Greek and Roman literature. There is a considerable seam of fantasy in the various materials incorporated into Aesopic fable; it is at its richest where animals are credited with human education and particularly rhetorical effusiveness, whether in boastful mock-Epic speeches or sophistic display. The convention of enabling animals to talk defines the genre. Babrius accordingly attributes the animal fable to the Golden Age: In the Golden Age the rest of living creatures could articulate in speech and knew such words as use when speaking to each other. A mythology grows up over fable itself; if Babrius can attribute animal fable to the Golden Age, Philostratus has a typical creation myth, after Plato’s Protagoras, about the origin of fable: Once upon a time Hermes gave out the different kinds of gifts to all the great men.