In two previous papers on the prospects for intelligent legal information systems 122, 271, I advocated the development of “deep conceptual models” of particular legal domains. My motivation was both… (More)

D Clausal intuitionistic logic is an extension of Horn-clause logic which permits the appearance of negations and embedded implications on the right-hand side of a rule, and interprets these new… (More)

Intuitionistic logic programming is an extension of Horn-clause logic programming in which implications may appear “embedded” on the right-hand side of a rule. Thus, rules of the form A(x) ← [B(x) ←… (More)

D Since the advent of Horn-clause logic programming in the mid 1970’s, there have been numerous attempts to extend the expressive power of Horn-clause logic while preserving some of its attractive… (More)

This paper combines a system of deontic logic with a system for default reasoning to analyze a notorious philosophical problem: Chisholm’s Paradox. The basic approach is to write deontic rules with… (More)

Everyone knows that lawyers are trained in the art of argument. But what exactly does this mean? Is a legal argument a chain of valid inferences, grounded in authoritative rules? Or is it merely a… (More)

Eisner v. Macomber , 252 U.S. 189 (1920), a corporate tax case, was the principal illustration of a theory of legal reasoning and legal argumentation proposed more than ten years ago. Although the… (More)

One of tha principal goals of tha TAXMAN project is to develop a theory about the structure and dynamics of legal concapts, using corporate tax law as an experimental problem domain In this paper we… (More)

This article describes a formal semantics fo r the deontic concepts the concepts of permiss ion and ob l iga t ion — which arises naturally f r o m the representations used in artif icial… (More)