How We Reason

Good reasoning can lead to success; bad reasoning can lead to catastrophe. Yet, its not obvious how we reason, and why we make mistakes - so much of our mental life goes on outside our awareness. In recent years huge strides have been made into developing a scientific understanding of reasoning. This new book by one of the pioneers of the field, Philip Johnson-Laird, looks at the mental processes that underlie our reasoning. It provides the most accessible account yet of thescience of reasoning. We can all reason from our childhood onwards - but how? How we reason outlines a bold approach to understanding reasoning. According to this approach, we dont rely on the laws of logic or probability - we reason by thinking about whats possible, we reason by seeing what is common to the possibilities. As the book shows, this approach can answer many of the questions about how we reason, and what causes mistakes in our reasoning that can lead to disasters such as Chernobyl. It shows why ourirrational fears may become psychological illnesses, why terrorists develop crazy ideologies, and how we can act in order to improve our reasoning. The book ends by looking at the role of reasoning in three extraordinary case histories:: the Wright brothers use of analogies in inventing theirflyer, the cryptanalysts deductions in breaking the Germans Enigma code in World War II, and Dr. John Snows inductive reasoning in discovering how cholera spread from one person to another. Accessible, stimulating, and controversial, How we Reason presents a bold new approach to understanding one of the most intriguing facets of being human.