Behave is over 700 pages long. Its size may lead to some potential readers being intimidated, but I found it an engaging, often entertaining review of neuroscience, from the lens of someone who has good experience and understanding not just of brain chemistry, but of social, historical, and psychological influences upon behaviour.
One of Sapolsky's big messages, in a nutshell, is that very few single factors (such as hormone or neurotransmitter effects, genes, or environmental incidents) have a simple, obvious, consistent impact. These factors have different effects depending on the circumstances. For example, androgens may only exacerbate aggressive behaviour in someone who is already having difficulties containing aggression in the first place. This immediately makes me question the generic finding (recently published) that violent video games have no negative impact...perhaps there is a negative impact, but only in those who have violent behavioural tendencies in the first place.
On the one hand, this is a refreshing antidote to the simplistic reductionism that is often presented in discussions of neuroscience or psychiatry. On the other hand, it does not negate the importance of studying these factors with good scientific depth, so as to work with them therapeutically, on a neurobiologic or societal level.
A criticism I do have about the book is his references to areas of the psychological literature (such as about priming, for example) which are now being questioned: a lot of findings about priming seem to have failed replication tests, and so I'm not sure what to think about this whole area anymore. I suspect influences such as priming do exist, but may be more transient or erratic than what the original literature suggested.
I appreciate his balanced analysis of the work of other thinkers, such as Steven Pinker, and other historical figures in psychology such as Zimbardo.
I most appreciate his message of hope, about the things we can all work on to live more peacefully, in light of the influences (positive and negative) upon our behaviour that we are born into, through our genes, family, and culture.
This is another type of book that I wish students could be exposed to as part of their university education about psychology, medicine, or other areas of the humanities.