1 Historical review: Some topics are better understood if a brief historical review of the topic is presented to lead into the discussion of the moment. Such topics might include "a biographical sketch of a war hero," "an upcoming execution of a convicted criminal," or "drugs and the younger generation." Obviously there are many, many more topics that could be introduced by reviewing the history of the topic before the writer gets down to the nitty gritty of his paper. It is important that the historical review be brief so that it does not take over the paper.
A thesis statement makes a claim about the topic and why the writer believes this is true. For instance, the writer in the example thesis statement shows that she believes that stress, depression and anger may lead to eating disorders. It gives an argument about eating disorders and the reader will know exactly what the writer is planning to prove. However, some people may not agree with the writer. Some people may believe that stress is not related to eating disorders. Some people might believe that depression or anger has nothing to do with eating disorders. A good thesis statement allows the reader to disagree with it but it encourages the reader to read to find out more about the topic.