Value-based Practical Reasoning

CRRAR Surely one of the most important contributions of Trevor Bench-Capon to computer science, and especially to artificial intelligence and law, and for that matter to argumentation theory and cognitive science generally, is the model of value-based practical reasoning he has given us. He introduced value-based argumentation frameworks (VAF's) in (Bench-Capon, 2002; Bench-Capon, 2002a; Bench-Capon, 2003). He then applied this framework to practical reasoning, yielding the argumentation scheme for value-based practical reasoning, in a series of papers with his colleagues Katie Atkinson and Peter McBurney. Greenwood was the unmarried name of Katie Atkinson.The first one appears to be (Greenwood, Bench-Capon and McBurney, 2003). Before 2003 there had been several books and numerous articles written on the subject of practical reasoning, and of course the notion originally derived from Aristotle. The literature in philosophy was almost exclusively concentrated on what could be called instrumental practical reasoning, a notion that did not take values explicitly into account, even though some philosophers recognized the importance of values in practical reasoning. But the only argumentation model of practical reasoning previously put forward (Walton, 1992) concentrated exclusively on instrumental practical reasoning, the assumption being that the values-laden variant contained so many complexities of its own that getting a basic notion of practical reasoning without considering the role of values in it was the best place to start. Previous to 2002, there was simply no idea of how a value-based model of practical reasoning could be added on to the existing argumentation model. Much less was there any idea of how such a notion of value-based practical reasoning could be formally modeled or implemented computationally. So what Trevor and his colleagues have given us is a tool of no small importance for many fields. The significance of the potential applications and philosophical implications of it should not be taken lightly. Having a value-based version of the argumentation scheme for practical reasoning will no doubt prove to be extremely useful, not only in the field of artificial intelligence and law, but in many applications of argumentation theory and methods, including law itself. But there are many questions that arise concerning the relationship between the new value-based version of practical reasoning and the old simpler model of practical reasoning that does not take values into account. Also, there are more critical questions matching the value-based version of the scheme, and therefore questions are raised generally about how both …