There are two specific forms of literature being satirized in "The Nun's Priest's Tale," the epic and the beast fable. On the human level, Chaucer creates a mock epic, making a roster its hero. The story shows the superstition of dream interpretation, the danger of listening to women, and the problem of pride. Obviously, the problem with pride is the actual moral being displayed, with the others serving as humorous satire. These ideas themselves are very human and quite relatable, especially in the time period Chaucer wrote in.
The tale also constitutes a beast fable, personifying animals and giving them human problems to work out. The animals allow for the themes to be accomplished. The animals also allow for the satirie to achieve its purpose, as beast fables are generally considered children's stories and normally communicate some sort of universal moral. The moral shown here is the problem of pride and the problem of speaking when you should be silent.