A Contractualist Argumentation Framework for Moral Decision-Making

2026-08-03

AI Summary

This work addresses the challenge of moral decision-making for autonomous agents operating in shared environments where conflicting interests arise, necessitating a systematic reasoning mechanism grounded in defensible ethical principles. It presents the first formalization of Scanlonian contractualist ethics into a computable argumentation framework by extending the ASPIC+ structured argumentation system. The proposed approach incorporates a value-driven belief-filtering mechanism and an argument semantics that enables agents to generate, compare, and evaluate moral reasons according to the principle that no one could reasonably reject them. Empirical validation in domestic scenarios demonstrates the framework’s practical efficacy, while theoretical analysis reveals its advantages over existing value-based argumentation methods and delineates its precise scope of applicability.

Abstract

Autonomous agents operating in shared environments must make decisions that affect multiple individuals with potentially conflicting interests. We propose a formal framework for moral decision-making grounded in Scanlon's contractualism, an ethical theory that evaluates the permissibility of actions in terms of principles that no one could reasonably reject. To operationalise contractualist reasoning, we use ASPIC+, a structured argumentation framework, extended with value-based filtering to model how each agent's values determine which reasons are morally relevant in the first place. The result is a Contractualist Argumentation Framework in which agents' reasons are formally represented, compared, and evaluated through argumentation semantics. We illustrate the approach through a worked example in a domestic setting and discuss its relation to existing value-based argumentation approaches.

Problem

• moral decision-making
• contractualism
• autonomous agents
• value-based argumentation
• conflicting interests

Innovation

• contractualism
• argumentation framework
• value-based filtering
• moral decision-making
• ASPIC+