Abstract. In 2005, Gordon and Walton presented initial ideas for a computational model of defeasible argument [12, 26], which builds on and elaborates Walton's theory of argumentation [28, 31]. The current paper reports on progress which has been made in the meantime. It presents a formal, mathematical model of argument evaluation which applies proof standards [8] to determine the defensibility of arguments and the acceptability of statements on an issue-by-issue basis. The main original contribution of the Carneades Argumentation Framework is its use of three kinds of premises (ordinary premises, presumptions and exceptions) and information about the dialectical status of statements (undisputed, at issue, accepted or rejected) to model critical questions in such a way as to allow the burden of proof to be allocated to the proponent or the respondent, as appropriate. Both of these elements are required for this purpose: presumptions hold without supporting argument only so long as...
Thomas F. Gordon, Douglas Walton