Title: Modelling morality with prospective logic

Authors: Luis Moniz Pereira, Ari Saptawijaya

Addresses: Centro de Inteligencia Artificial – CENTRIA, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal. ' Fakultas Ilmu Komputer, Universitas Indonesia, 16424 Depok, Jawa Barat, Indonesia

Abstract: This paper shows how moral decisions can be drawn computationally by using prospective logic programs. These are employed to model moral dilemmas, as they are able to prospectively look ahead at the consequences of hypothetical moral judgments. With this knowledge of consequences, moral rules are then used to decide the appropriate moral judgments. The whole moral reasoning is achieved via a priori constraints and a posteriori preferences on abductive stable models, two features available in prospective logic programming. In this work, we model various moral dilemmas taken from the classic trolley problem and employ the principle of double effect as the moral rule. Our experiments show that preferred moral decisions, i.e., those following the principle of double effect, are successfully delivered. Additionally, we consider another moral principle, the principle of triple effect, in our implementation. We show that our prospective logic programs allow us to explain computationally different moral judgments that are drawn from these two slightly but distinctively different moral principles.

Keywords: morality modelling; computational morality; moral reasoning; trolley problem; double effect principle; triple effect principle; prospective logic; abductive stable models; ACORDA; intelligent systems; moral decisions; moral judgments; moral dilemmas.

DOI: 10.1504/IJRIS.2009.028020

International Journal of Reasoning-based Intelligent Systems, 2009 Vol.1 No.3/4, pp.209 - 221

Published online: 27 Aug 2009 *

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