The author uses the concept of two minds to explain how our brain makes decision, and how we're prone to succumb to bad decision making in situations ranging from being able to see the reality in optical illusions to why we sometimes prefer to repeat situations that are clearly more painful than others.
He explains experiments and dissects various situations where our decision can change 180˚ just because the way it is presented. Like the fact that anyone is more likely to accept treatment if it is presented in terms of percentage of survival instead of death.
It also covers the interesting topic on how we think of losses and gains in different situations, and how we scale them while making a decision.
It is a long, but very pleasant read. Life changing, for sure, and I highly recommend it!