Automated Reasoning in Normative Detachment Structures with Ideal Conditions

TL;DR

This paper introduces a simple yet expressive deontic logic that avoids paradoxes and effectively captures contrary-to-duty reasoning, demonstrated through automated reasoning on legal texts.

Contribution

It proposes a new logic for normative reasoning that balances expressiveness and mechanizability, and applies it to analyze legal normative structures.

Findings

The logic avoids common deontic paradoxes.

It effectively models contrary-to-duty reasoning.

Automated reasoning is demonstrated on legal texts.

Abstract

Systems of deontic logic suffer either from being too expressive and therefore hard to mechanize, or from being too simple to capture relevant aspects of normative reasoning. In this article we look for a suitable way in between: the automation of a simple logic of normative ideality and sub-ideality that is not affected by many deontic paradoxes and that is expressive enough to capture contrary-to-duty reason- ing. We show that this logic is very useful to reason on normative scenarios from which one can extract a certain kind of argumentative structure, called a Normative Detachment Structure with Ideal Conditions. The theoretical analysis of the logic is accompanied by examples of automated reasoning on a concrete legal text.