Greetings!
My suggestion would be that you sit down with your
dissertation adviser to discuss how to handle this. It sounds as if you are asking me to specifically define your dissertation thesis for you, and I don't feel that would be an appropriate thing for me to do, as you will be having to spend several months researching and writing your dissertation, and need to be comfortable with the direction you have chosen. Simply writing that the Grapes of Wrath contains the theme of the saving power of the family and friendship is not going to be in-depth enough, but I don't know your background, or why you picked this topic, or what type of degree this is for, or what previous dissertations have been written on the topic before, or any of the myriad other things I would need to know to advise you what, specifically, your dissertation should be about. I think you need to discuss this with someone in your major's department, an adviser, if you have one.
Best of luck in your studies!
Thanks,
Sarah, EssayForum.com
Sarah, EssayForum.com