As renowned primatologist and neurobiologist Robert Sapolsky says, if you want to understand human behavior and the nature of a good or bad deed, you have to understand literally everything—from what happened a second before to what happened millions of years ago. In the book, the author examines step by step—one might say, chronologically—and in great detail the vast number of factors that influence our behavior. How does our brain work? What is the amygdala responsible for, and what should we thank the frontal cortex for? What does the insula 'hate'? Why do London taxi drivers have an enlarged hippocampus? What is the connection between the length of the index and ring fingers and the amount of prenatal testosterone? How do teenagers differ from children and adults from a neurobiological perspective? Are there 'pure' altruists? What is the difference between forgiveness and reconciliation? Does free will exist? How do complex social connections influence our behavior and decision-making? And these are just a few of the questions addressed in this renowned scientist's extensive work.