A topic is not a thesis. The topic is designed to be general; it allows you to develop your own ideas and understanding of the text into your own point of view on the topic (but you must support it with evidence from the poem). One way to know if you have a strong thesis is to ask yourself, "Could anyone disagree?" If not (or if the disagreement could only be slight or weak), you probably have little or no thesis.
You will realize from this that a literary analysis (whether it contains research or not) is very different from a report. A report might be about the way women were treated in ancient Greece. It would contain a lot of information, but it would have no point--except, of course, to summarize other people's work on women in ancient Greece. Reports are uncreative. They do not tax your brain--only your ability to shuffle paper and present information correctly. They are a pain to do but not very useful for gauging a person's insight into a subject or work of literature.
For example:
N.B.: A thesis cannot be either a question or a fact.
Consider the following weak theses:
(N.B.: A thesis may never begin "The purpose of this paper is . . ." or "In this paper I intend to . . .")
It is entirely cricket to decide on or to change your thesis after you have written a draft.
NOTE: A thesis generally (in 99% of papers) belongs at the end of your introduction (the length of which will vary with the length of the entire analysis), and each and every paragraph should carry out the idea in your thesis.
A word to the wise: the narrower (more specific, more focussed) your thesis is, the more likely it is that you will write a good, sound, meaningful analysis. Choosing the largest possible subject = writing the most superficial essay. If your thesis does not force you to get into the poem up to your armpits, i.e., force you to quote specific passages and explain them, you are in trouble.
And another: if you find yourself retelling the story in your essay, something is wrong with your thesis--or you are not sticking to it. If you find yourself stuck in the storytelling mode, try reorganizing your paper so that you do not deal with your ideas in the order the story goes. By forcing yourself to begin with something that happens in the middle and then taking examples from the early part of the work, you will break up the "pull" the story has on you.
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