Good reasoning can lead to success; bad reasoning can lead to catastrophe. Yet, it is not obvious how humans reason, and why humans make mistakes. In recent years huge strides have been made into developing a scientific understanding of reasoning. This book looks at the mental processes that underlie a human's reasoning. We can all reason from childhood onwards — but how? The book outlines an approach to understanding reasoning, according to which, humans don't rely on the laws of logic or probability — they reason by thinking about what's possible, by seeing what is common to the possibilitie ... More

Good reasoning can lead to success; bad reasoning can lead to catastrophe. Yet, it is not obvious how humans reason, and why humans make mistakes. In recent years huge strides have been made into developing a scientific understanding of reasoning. This book looks at the mental processes that underlie a human's reasoning. We can all reason from childhood onwards — but how? The book outlines an approach to understanding reasoning, according to which, humans don't rely on the laws of logic or probability — they reason by thinking about what's possible, by seeing what is common to the possibilities. As it shows, this approach can answer many of the questions about how humans reason and what causes mistakes in reasoning that can lead to disasters such as Chernobyl. It shows why irrational fears may become psychological illnesses, why terrorists develop ‘crazy’ ideologies, and how humans can act in order to improve reasoning. The book ends by looking at the role of reasoning in three case histories: the Wright brothers' use of analogies in inventing their flyer, the cryptanalysts' deductions in breaking the German's Enigma code in World War II, and Dr. John Snow's inductive reasoning in discovering how cholera spread from one person to another.