Nevertheless, the potential and actual importance of fantastic literature lies in such psychic links: what appears to be the result of an overweening imagination, boldly and arbitrarily defying the laws of time, space and ordered causality, is closely connected with, and structured by, the categories of the subconscious, the inner impulses of man's nature. At first glance the scope of fantastic literature, free as it is from the restrictions of natural law, appears to be unlimited. A closer look, however, will show that a few dominant themes and motifs constantly recur: deals with the Devil; returns from the grave for revenge or atonement; invisible creatures; vampires; werewolves; golems; animated puppets or automatons; witchcraft and sorcery; human organs operating as separate entities, and so on. Fantastic literature is a kind of fiction that always leads us back to ourselves, however exotic the presentation; and the objects and events, however bizarre they seem, are simply externalizations of inner psychic states. This may often be mere mummery, but on occasion it seems to touch the heart in its inmost depths and become great literature.