The excerpt that best supports the theme that there was a sense of hope that the city would rebuild after the fire is:
“Alfred Sewell ended his discussion of Chicago with a stirring prediction: ‘The city will nevertheless rise again, nay, is already rising, like the Phoenix, from her ashes. And she will, we believe, be a better city as well as a greater one, than she was before her disaster.’”
This passage expresses a clear optimism about the future of the city, suggesting not only a rebuild but also an improvement over the past.