In Jackson's "The Lottery" amidst laughter and gossip, a cheerful well-dressed business-man directs a ritualist act in which an entire town unthinkingly engages. Like stories such as "The Tell-Tale Heart" and "The Black Cat" of Edgar Allan Poe, the horror arises from the skewered perception of what is considered ordinary or normal. It is often this twist of events and point of view which make the stories horrific. In "The Lottery," for instance, the people who have just conversed with Tessie Hutchinson are able to hurl stones at her simply because it is her lot to die; the reasons why she is being stoned have long been forgotten by the people. That people can be so inured to another person's victimization and to the horrible consequences of an act for which they have forgotten the reason, is truly horrific.
Think of other stories that you may have read that fall into the genre of "gothic literature," and isolate what makes them horrifying. Then, base your thesis on a general statement (with three specific points that you can support) formed from this idea. Perception on the part of character(s) often seems to be the key.
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