Informal Logic is an introductory guidebook to the basic principles of constructing sound arguments and criticizing bad ones. Non-technical in approach, it is based on 186 examples, which Douglas Walton, a leading authority in the field of informal logic, discusses and evaluates in clear, illustrative detail. Walton explains how errors, fallacies, and other key failures of argument occur. He shows how correct uses of argument are based on sound strategies for reasoned persuasion and critical responses. Among the many subjects covered are: forms of valid argument, defeasible arguments, relevance, appeals to emotion, personal attack, straw man argument, jumping to a conclusion, uses and abuses of expert opinion, problems in drawing conclusions from polls and statistics, loaded terms, equivocation, arguments from analogy, and techniques of posing, replying to, and criticizing questions. This new edition takes into account many new developments in the field of argumentation study that have occurred since 1989, many created by the author. Drawing on these developments, Walton includes and analyzes 36 new topical examples and also brings in recent work on argumentation schemes. Ideally suited for use in courses in informal logic and introduction to philosophy, this book will also be valuable to students of pragmatics, rhetoric, and speech communication.