Judging Actions on the Basis of Prima Facie Duties. The case of self-driving cars

Piotr Kulicki, Robert Trypuz

DOI: http://dx.doi.org/10.12775/LLP.2019.006


The need for a logic that allows us to reason about conflicting and non-conflicting norms has recently emerged in the domain of self-driving cars. In this paper we propose a formal model that supports moral decisions making by autonomous agents such as for example autonomous vehicles. Such a model – which we call a “Deontic Machine” – helps resolve both typical and atypical moral and legal situations that agents may encounter. The Deontic Machine has two sources of inspiration. The first one is W.D. Ross’s theory of prima facie norms and the other one is a deontic multi-valued logic. The main contribution of this paper is bringing together conceptual and technical tools of deontic logic to show how they can be used to control or assess the behaviour of a self-driving car.


autonomous agents; self-driving cars; conflict of norms; multi-valued deontic logic; practical reasoning; prima facie norms; Prolog

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