This is one of those books that I want to call "simply delightful" and it's simply... not the right phrase to use at all. But not because it's not a delight to read.
What I mean by delightful is the manner in which Whitehead's intent slowly makes itself known to you as you read. I'm fairly certain I did not start to wonder what he was up to until the end of the first major section, after the first trip on the underground railroad. I remember my eyebrows reaching to the ceiling, and putting the book down, and pondering for a long while. If you know me, you know that doesn't happen very often!
After that, it was taking his journey, in which he re-envisions the South, slavery, the resistance movement, and the entire railroad itself. The result of taking that journey is to, quite honestly, be put inside the shoes of blacks both then and now, to get a better feeling for hurdles and troubles that are not always commonly understood.
For instance, what would it feel like to live in Indiana at this time (or a slightly modified time)? Or, what would it have been like to live in a supposedly enlightened Southern state? If anyone is able to create a book that engages the reader and teaches these carefully crafted concepts at the same time (as opposed to the last Pulitzer winner I read...), Whitehead is that man. And, if you've never heard him speak, absolutely go do that as well.