I loved this provocative, intriguing book, even when I disagreed with Eagleman's points. Much of the book explores how the brain works with some freakonomics-style experiments (for example, men rate women as more attractive when their pupils are dilated, a sign of sexual arousal that men read subconsciously) and some curious instances where normal brain function is disrupted (like the inability to see motion). These studies are fascinating and thought-provoking.

A major section of the book offends my sensibilities as a criminal defense lawyer, even though I still rate the book five stars. This is the part, near the end, where Eagleman proposes a criminal justice system that looks to preventing future misconduct instead of just punishing past misconduct. I like that Eagleman recognizes the difficulties of his proposal, and that he wants a justice system that looks at individuals as more than just faceless numbers to place into some sentencing grid. However, punishing someone for crimes not yet committed offends many fundamental notions of justice. In Massachusetts (and some other states), someone convicted of certain sex crimes can be civilly committed for a day to life on the basis of an opinion (often made using demonstrably flawed actuarial tools) that he or she is a sexually dangerous person likely to reoffend. This seems like a simple scientific procedure, but it depends so much on subjective guesswork and personal biases that it is far from fair. I start to get angry when I think of such a horrible process being expanded from simply convicted sex offenders (who are certainly entitled to justice and fair treatment, but at least they are a small population so the catastrophic harm at least has a limited number of potential victims) to anyone caught up in the criminal justice system. Eagleman's proposal is logical, founded on thorough research, and completely inhumane.

Also, I find it curious that Eagleman's work has so many subtle jabs at religion and spirituality. He posits natural selection reasons for each neurological characteristic that he is able to describe at any length and doesn't leave any room for a theory of, "Or maybe some kind of higher power designed that piece that way," which requires just as much faith, I think. I am also fascinated by the way he finds proof for a subconscious in people responding to spontaneous ideas that many religious traditions would describe as divinely inspired. Plus, he explores the idea that there is no basis in neurology for the idea of the soul, when I don't know that many people concerned with the existence of a soul particularly care whether or not neuroscience supports their belief. Certainly, I am not offended by Eagleman's attitude toward spirituality in this book - I just find it curious, especially for someone associated with the Baylor University system, an institution with strong ties to the Baptist Church.

In the end, I loved this book. I learned a great deal about the role of the subconscious and the workings of the brain, and it was presented in a style that was not too academic and not too casual. I hope that this becomes a textbook in college freshmen psych classes, at least to get some good conversations started about what we know and what we think we know about how we function.