This brick of a book purports to be an interdisciplinary explanation of human behavior, drawing from biology, psychology, and sociology, and everything from primate studies to well-known works in various fields. It’s big, at 717 pages of actual text followed by references; it’s broad; and as such it’s a little bit simplistic. Even at this size, there’s not quite room to develop all of the material. The first half or so of the book is more focused on the “hard” science, beginning with how neurons communicate with each other, and working its way up through hormones, genes, brain development through childhood and adulthood and how this is affected by trauma, and the evolution of species. The second half is more focused on psychology: us vs. them dichotomies, moral decisionmaking, the causes of violence, and whether the criminal justice system really makes sense when all human behavior is ultimately driven by biology. (Sapolsky argues no, but I’m not so sure. Where would we be as a species, or as individuals, if we all just shrugged our shoulders and gave in to ideas of biological determinism?)
I certainly learned a lot from this book, which contains a ton of information presented in a way that is understandable to a non-scientist – though I struggled a bit with some of the early chapters. It provides a strong synthesis and framework for understanding information from biology and social sciences. That said, on the subjects that I did know something about, it seemed a little simplified. Fair enough; entire books have been written on subjects that comprise a single chapter here. As other reviewers have suggested, Sapolsky perhaps accepts too many psychological studies uncritically, without discussing psychology’s replication crisis, in which dozens of famous studies, when run again using the exact same methods and parameters, failed to produce the same headline-worthy results. That said, in general Sapolsky seems to take a fair approach to his material, presenting and evaluating multiple viewpoints in areas that have generated controversy. His writing is readable given the subject matter, and there’s a goofy-professor personality behind it that occasionally shines through. I wouldn’t take everything here as gospel – and I suppose we never should, since new scientific discoveries regularly require us to reevaluate what we thought was true – but the book did leave me a little more educated than I was before.