A thesis statement defines the scope and purpose of the paper. It needs to meet three criteria:
1. It must be arguable rather than a statement of fact. It should also say something original about the topic.
  Bad thesis: Lily Bart experiences the constraints of many social conventions in The House of Mirth. [Of course she does. What does she do with these social conventions, and how does she respond to them? What's your argument about this idea?]
  Better thesis: Lily Bart seeks to escape from the social conventions of her class in The House of Mirth, but her competing desires for a place in Selden's "republic of the spirit" and in the social world of New York cause her to gamble away her chances for a place in either world. [You could then mention the specific scenes that you will discuss.]
2. It must be limited enough so that the paper develops in some depth.
  Bad thesis: Lily Bart and Clare Kendry are alike in some ways, but different in many others. [What ways?]
  Better thesis: Lily Bart and Clare Kendry share a desire to "pass" in their respective social worlds, but their need to take risks and to reject those worlds leads to their destruction.
3. It must be unified so that the paper does not stray from the topic.
  Bad thesis: Lily Bart gambles with her future, and Lawrence Selden is only a spectator rather than a hero of The House of Mirth. [Note: This is really the beginning of two different thesis statements.]
  Better thesis: In The House of Mirth, Lawrence Selden is a spectator who prefers to watch and judge Lily than to help her. By failing to assist her on three separate occasions, he is revealed as less a hero of the novel than as the man responsible for Lily's downfall. [Note: Sometimes thesis statements are more than one sentence long.]
4. Statements such as "In this essay I will discuss " or "I will compare two stories in this paper" or "I was interested in Marji's relationship with God, so I thought I would talk about it in this essay" are not thesis statements and are unnecessary, since mentioning the stories in the introduction already tells the reader this.
Explanation:
