Formalizing the Moral Evaluation of Speech Acts: Truthfulness, Lies and Ethical Dilemmas

2026-10-03

AI Summary

This study addresses the challenge of balancing intentions and consequences in the moral evaluation of speech acts, such as lying, within life-and-death scenarios. To this end, it proposes a belief-based, generalized parameterized logical framework that leverages Answer Set Programming (ASP) to integrate deontological and consequentialist principles for multi-criteria ethical reasoning, enabling adaptation to novel moral contexts without modifying underlying rules. As a key contribution, this work successfully reproduces the classic ethical dilemma depicted in Sartre’s *The Wall*, thereby validating the framework’s applicability and interpretability in complex scenarios. Ultimately, this research establishes a new paradigm for flexible yet rigorous machine ethics computation.

Abstract

In life-or-death situations, a benevolent lie may appear more moral than telling the truth. Yet such lies can backfire, producing unintended and sometimes fatal consequences. This tension, famously disputed by Kant and Constant in 1797, applies not only to lying but to assertive speech acts in general, raising the question of which utterance should be chosen when moral stakes are high. We present a logical framework for the ethical evaluation of speech-act utterances based on agents'beliefs. Implemented in Answer Set Programming (ASP), the framework assesses utterances under deontologism, consequentialism, and principialism, and is illustrated on Sartre's The Wall (1939), a reworking of that controversy in which lying leads alternately to rescue and to death. Our setting is general by design: as two variants show, accommodating a new moral situation amounts to adjusting parameters, not rules.

Problem

• moral evaluation
• speech acts
• ethical dilemmas
• truthfulness
• lies

Innovation

• Answer Set Programming
• Moral Evaluation
• Speech Acts
• Logical Framework
• Ethical Dilemmas