The title of this book is a bit misleading. It's not really about the science behind Pratchett's famous, flat world, carried on the back of a giant turtle. Rather, it's how the science that made our universe, so different from that in this fictional realm, baffles the smartest men on Discworld, the magicians. It's about two places at complete odds with each other, one vastly more advanced must come to terms with the chaos of the other (we're the "other.")
Why is our universe so baffling to the learned men of Unseen University? Well, in our universe, planets are round, Discworld is flat. Our universe is governed by rules (aka science), Discworld runs on magic. Change in our universe is propelled by scientific processes like evolution, but on Discworld, narrativium drives the story. To make things even more confusing for our Discworld natives, they encounter our universe at its very start, observing the first blob that forms the basis for our reality. Things move slowly, even with slight interference from Unseen University's best and brightest, leading to the generally accepted opinion that our world isn't a success and should just be done away with immediately.
Chapters swap between the observations of the Discworld professors and Earth-bound science lessons related to the creation of our universe and the development of our planet. Essentially, The Science of Discworld, is a science book with a science fiction wrapper. Discworld chapters infuse the science with humor and philosophical questions to ponder, like what would happen if an Unseen Univ. professor stuck his finger into our universe as it was forming, while the scientific chapters educate you.
Both silly and informative, this is a very unique approach to quite a few basic science lessons. While I had hoped the book would be more about the origins and development of Discworld itself, I didn't mind that I learned a little something about my own planet. Denser than a typical Discworld book, more like a lighter science textbook, it was still a good read that gave me a few things to think about.
A few other books in the Discworld series to check out include: