I really enjoyed this book in the beginning. Some of the concepts were difficult, but Greene knows how to build a good analogy and make physics easier to understand for the reader. Unfortunately, I started to lose interest a little after the halfway mark. Once Greene starts expanding on humans and our minds, it reminded me of Harari's "Sapiens" which I just recently read so it was a little repetitive and I don't feel Greene had anything new to add to the conversation. The ending was okay, with another good metaphor using the Empire State building as a model for our universe, but overall I felt a little unsatisfied.