Canadian academic and author (1942–2020)
Douglas Neil Walton (2 June 1942 – 3 January 2020) was a Canadian academic and author, known for his books and papers on argumentation, logical fallacies and informal logic. He was a Distinguished Research Fellow of the Centre for Research in Reasoning, Argumentation, and Rhetoric (CRRAR) at the University of Windsor, Ontario, 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.
A special issue of the journal "Informal Logic" surveyed Walton's contributions to informal logic and argumentation theory up to 2006.
Education.
Walton earned his PhD from the University of Toronto in 1972.
Work.
Walton's work represents a distinctive approach built around a set of practical methods to help a user identify, analyze, and evaluate arguments in specialized areas such as law and science, as well as arguments of the kind used in everyday conversational discourse. Walton has called this approach logical argumentation, and as a method it has twelve defining characteristics, shown below in a simplified list. 
In the method, schemes work as heuristic devices that only offer presumptive support of a claim that may have to be withdrawn as new evidence comes in. The schemes connect arguments together into sequences, often called chaining, by taking the conclusion of one argument as a premise in a subsequent argument. Some common schemes are argument from goal-based reasoning, argument from negative consequences, argument from positive consequences, inference to the best explanation (abductive reasoning), argument from sign, argument from analogy, argument from precedent, argument from an established rule, argument from evidence to a hypothesis, argument from cause to effect, argument from correlation to cause, argument from sunk costs, argument from threat, argument from perception, argument from witness testimony, argument from expert opinion, argument from ignorance, argument from commitment, direct ad hominem argument, argument from inconsistency of commitments, slippery slope argument.
References.
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