Argumentation, Rationality and Decision
Imperial College London, 18th-19th September 2014
Argumentation, initially studied in philosophy and law, has in recent years been the subject of extensive formal research in artificial intelligence and computer science. It provides representations and algorithms for reasoning with incomplete and possibly inconsistent information. Formalisms can be used to model decision-making by individual agents performing critical thinking or by multiple entities dialectically engaged to reach mutually acceptable decisions. However, so far there has been little engagement with the rich mathematical theories of decision, studied as part of microeconomic theory.
In turn, formal rational choice theory has paid little attention to the structure and content of arguments brought to bear on decisions. The outcomes of choices are typically assigned values treated as embodying a cardinal or ordinal preference relation, with decision rules identifying good choices according to various decision rules and under differing conditions of circumstantial knowledge (certainty, strict uncertainty, risk). However, when people make decisions, whether that process has been rational or not depends not only on the optimality of outcome, but also on the argumentative structure implicit in the person’s deliberation. The structure of argument is important, and arguments for and against choices are weighed against each other depending on how firm the reasons are from which the argument is formed.