by Daniel Kahneman

This book is helps give a fundamental understand of the important differences between the conscious and the subconsious mind, which are both always active and play critical roles in every one of your thought processes.

The central thesis is that there exist two modes of thought: 

1. "System 1" is fast, instinctive and emotional. You can think of it as "subconscious thought" and this part of the brain is effectively shared with all other mammals.
2. "System 2" is slower, more deliberative, and more logical. It's the only part of our thinking we're really aware of, because it's the part that has language. As a part of our thinking, the thoughts that enter our consciousness are entirely based on the information captured processed (outside of our awareness) by System 1.

Each system is specific strengths and weaknesses, including cognitive biases, that need to be understood in order to think usefully.

The book highlights several decades of academic research to suggest that people place too much confidence in human judgment, specific to System 2's conscious, rational thinking. In simple terms, be believe our thoughts too much, even though there is no evidence they are true. This fundamental attachment to those beliefs ("my thoughts are true") is one of the key underlying mechanims of depression, psychological addiction, the not good enough story (impostor syndrome), social anxiety, suicidal thoughts, and many many more unhepful areas of mistaken belief.

System 1 v System 2