Many years ago my husband and I realized that when we traveled, we did much better listening to our "gut" than to our rational mind. Whenever something went astray, one or both of us would say, "I had a feeling we should have done..." Giving precedence to our intuition was hard, because we both pride ourselves on our rationality and thinking things out. But we made a pact and have had more pleasant traveling experiences since. 
 Now I know why. Rational humans do not exist. The rational mind exists only to justify the judgements of the unconscious mind. The unconscious mind evolved over millennia to help us survive in a harsh environment but in the modern world can trip us up. From hiring people to choosing a car to estimating time for projects, we're usually rationalizing the conclusions of our unconscious--not always to our advantage. 
 Mlodinow--a theoretical physicist by training--collects an impressive amount of cutting edge neuroscience on the functions of the brain, and it's impact on behavior, in this book. He draws some startling conclusions. Some of the research, such as an unconscious bias against "others" (of whatever outgroup) and the tendency to disregard any evidence that contradicts closely held beliefs; I've been aware of for years. Other research into the malleability of memories was completely new (to me)--and horrifying! Mlodinow gives us some insight into how personal awareness of the unconscious can help mitigate its effects, but it's an uphill battle. 
 This is an important--and quite readable--book that has implications for social policy and personal insight. It's too bad more policy makers don't read this book. Of course, they may have, and completely dismissed it because it didn't fit their world view of being in complete control of their thoughts and actions.