I knew from reading The Beginning of Infinity that its precursor would be challenging. This book is Deutsch’s attempt at a grand unifying theory of reality based on his belief in a multiverse. I’m curious who he thought the audience was for this book? The content was intellectually difficult, yet it refrained from going into the specific mathematics of quantum mechanics (thankfully) which seems like a mandatory for the more scientifically-minded. Overall, Deutsch came across as cranky, defensive and exasperated at others that hold contending views. While this didn’t bother me, Deutsch’s propensity to methodically lay out points while rebutting every conceivable objection he could think of was frustrating. I wanted him to focus on communicating his “quantum perspective” with a simple clarity that I could understand—and stop contaminating his thesis with long-winded diatribes and ancillary information that served to insulate his opinions from criticism.This approach was head scratching. The average joe doesn’t have the capacity to poke holes in his work; at the same time, physicists will no doubt remain unconvinced without the presentation of the mathematical underpinnings. Reading the text was like listening to a highly adept lawyer building a technical case, but unfortunately it didn’t congeal at the end with a poignant and comprehensible conclusion for the jury to consider. I’m left with a nascent, but cloudy understanding of the multiverse, quantum mechanics, what constitutes physical reality and science’s role in knowledge creation. So again, I ask, who is the audience for the book? Someone smarter than me, that’s for sure. It is an ambitious text with big ideas and for that I have much to think about.