So far the most complex and complete book on the subject it describes.
This book offers detailed explanation on how our minds work when it comes to thinking, choosing, taking conscious and unconscious decisions, acting and reacting to outside stimulus.
It stands as reference to many marketing campaigns as it explains the pattern of decision making. Kahneman uses the two systems to offer an interesting perspective on how our choices are based on patterns that can be easily interfered with.
It also explains how our brain works in terms energy consumption, our second system, the slow thinking, consuming a lot more energy so the body is programmed to avoid it.As an example, try multiplying two two-digit numbers in your head while you are running. You will inevitably slow down.