Abstract specification of legal contracts

ABSTRACT

The paper presents an action-based formal language called CL for abstract specification of legal contracts. The purpose of the language is to be used to reason about legal contracts (and electronic contracts on the long run). CL combines the legal notions obligation, permission, and prohibition from deontic logic with the action modality of propositional dynamic logic (PDL). The deontic modalities are applied only over actions, thus following the ought-to-do approach. The language includes a synchrony operator to model "actions performed at the same time", and a special complementation operation to encode the violation of obligations. The language has a formal semantics in terms of normative structures, specially defined to capture several natural properties of legal contracts. We focus on the informal presentation of the choices made when designing CL, and its semantics.

REFERENCES

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• 6: Cristian Prisacariu , Gerardo Schneider, $\mathcal{CL}$: An Action-Based Logic for Reasoning about Contracts, Proceedings of the 16th International Workshop on Logic, Language, Information and Computation, June 21-24, 2009, Tokyo, Japan [doi>10.1007/978-3-642-02261-6_27]
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INDEX TERMS

Primary Classification:
  I. Computing Methodologies
  I.2 ARTIFICIAL INTELLIGENCE
      I.2.1 Applications and Expert Systems
          Subjects: Law

Additional Classification:
  D. Software
  D.3 PROGRAMMING LANGUAGES
      D.3.1 Formal Definitions and Theory

  F. Theory of Computation
  F.4 MATHEMATICAL LOGIC AND FORMAL LANGUAGES
      F.4.3 Formal Languages

  I. Computing Methodologies
  I.2 ARTIFICIAL INTELLIGENCE
      I.2.4 Knowledge Representation Formalisms and Methods

General Terms:
Legal Aspects, Theory