I was attracted to the premise of this book because I wondered why we reason the way we do. A sentence on the last page sums it up for me. “Group discussion is typically beneficial when participants have different ideas and a common goal.” In our times of polarization where we haven’t agreed upon the common goal of survival of the environment or humanity itself it is no wonder why we struggle. Hopefully insight into the ways we do and do not reason will help us discover a common goal. It only takes a serious illness to impress upon a person that individualism is an illusion. We will move forward together or not at all. Hugo Mercier and Dan Sperber have dug deep and given us the benefit of their exhaustive examination of the enigma of reason.