Appeal to Expert Opinion: Arguments from Authority

by Douglas N. Walton

A new pragmatic approach, based on the latest developments in argumentation theory, analyzing appeal to expert opinion as a form of argument.
Reliance on authority has always been a common recourse in argumentation, perhaps never more so than today in our highly technological society when knowledge has become so specialized-as manifested, for instance, in the frequent appearance of "expert witnesses" in courtrooms. When is an appeal to the opinion of an expert a reasonable type of argument to make, and when does it become a fallacy? This book provides a method for the evaluation of these appeals in everyday argumentation.

Specialized domains of knowledge such as science, medicine, law, and government policy have gradually taken over as the basis on which many of our rational decisions are made daily. Consequently, appeal to expert opinion in these areas has become a powerful type of argument. Challenging an argument based on expert scientific opinion, for example, has become as difficult as it once was to question religious authority.

Walton stresses that even in cases where expert opinion is divided, the effect of it can still be so powerful that it overwhelms an individual's ability to make a decision based on personal deliberation of what is right or wrong in a given situation. The book identifies the requirements that make an appeal to expert opinion a reasonable or unreasonable argument. Walton's new pragmatic approach analyzes that appeal as a distinctive form of argument, with an accompanying set of appropriate critical questions matching the form. Throughout the book, a historical survey of the key developments in the evolution of the argument from authority, dating from the time of the ancients, is given, and new light is shed on current problems of "junk science" and battles between experts in legal argumentation.

296 pages, Paperback

First published December 1, 1997

About the author

Douglas Neil Walton (PhD University of Toronto, 1972) is a Canadian academic and author, well known for his many widely published books and papers on argumentation, logical fallacies and informal logic. He is presently Distinguished Research Fellow of the Centre for Research in Reasoning, Argumentation, and Rhetoric (CRRAR) at the University of Windsor, Canada, and before that (2008-2014), he held the Assumption Chair of Argumentation Studies at the University of Windsor. Walton’s work has been used to better prepare legal arguments and to help develop artificial intelligence. His books have been translated worldwide, and he attracts students from many countries to study with him. A special issue of the journal Informal Logic surveyed Walton’s contributions to informal logic and argumentation theory up to 2006 (Informal Logic, 27(3), 2007). A festschrift honoring his contributions, Dialectics, Dialogue and Argumentation: An Examination of Douglas Walton’s Theories of Reasoning and Argument, ed. C. Reed and C. W. Tindale, London: College Publications, 2010, shows how his theories are increasingly finding applications in computer science. A list of titles of many of Walton’s books is given below. Links to preprints of many of his published papers can be found on the website

http://www.dougwalton.ca