I am writing a research paper on the book Oliver Twist and I need a thesis statement. not city vs. countryside?

I need to write a research paper on Oliver Twist and my original thesis was about comparing and contrasting the city and the countryside but it just isn't working. I've done all my research and I just cant write a paper on it. I am trying to come up with a thesis about how Oliver is not corrupted by his hardships and poverty but I cant put it into words. Any ideas?