In this wide range of human expression the ballad follows the epic as a kind of aftermath; a second and scattered harvest, springing without regularity or nurture out of a rich and unexhausted soil. The epic fastens upon some event of such commanding importance that it marks a main current of history; some story, historic, or mythologic; some incident susceptible of extended narrative treatment. It is always, in its popular form, a matter of growth it is direct, simple, free from didacticism; representing, as Aristotle says, "a single action, entire and complete." It subordinates character to action; it delights in episode and dialogue; it is content to tell the story as a story, and leave the moralization to hearers or readers. The popular ballad is so closely related to the popular epic that it may be said to reproduce its qualities and characteristics within a narrower compass, and on a smaller scale. It also is a piece of the memory of the people, or a creation of the imagination of the people; but the tradition or fact which it preserves is of local, rather than national importance. It is indifferent to nice distinctions and delicate gradations or shadings; its power springs from its directness, vigour, and simplicity. It is often entirely occupied with the narration or description of a single episode; it has no room for dialogue, but it often secures the effect of the dialogue by its unconventional freedom of phrase, and sometimes by the introduction of brief and compact charge and denial, question and reply. Sometimes the incidents upon which the ballad makers fastened, have a unity or connection with each other which hints at a complete story. The ballads which deal with Robin Hood are so numerous and so closely related that they constantly suggest, not only the possibility, but the probability of epic treatment. It is surprising that the richness of the material, and its notable illustrative quality, did not inspire some earlier Chaucer to combine the incidents in a sustained narrative. But the epic poet did not appear, and the most representative of English popular heroes remains the central figure in a series of detached episodes and adventures, preserved in a long line of disconnected ballads.