Thinking, Fast and Slow: Why We Make Foolish Choices Daniel Kahneman created "behavioral economics" by combining psychology and economics. He won the Nobel Prize in Economics for this work. Readers call his masterpiece, Thinking, Fast and Slow , the bible of psychology. It proves human irrationality using science. Traditional economics assumes humans act as rational beings (Homo Economicus) who maximize profit. Kahneman rejects this idea through experiments. Humans lack rationality and make decisions under cognitive illusions and biases. This book investigates how our brain works and why we repeat foolish choices across five parts. Part 1: Two Systems – The Lazy Controller in My Head The core of Part 1 shows that two different systems control human thought. Kahneman named them 'System 1' and 'System 2'. 1. Fast Thinking and Slow Thinking System 1 (Fast Thinking): It feels intuitive, automatic, and emotional. It operates without consciousness and uses little e...