We use a deontic logic of collective agency to study reducibility questions about collective agency and collective obligations. The logic that is at the basis of our study is a multi-modal logic in the tradition of *stit* logics of agency. Our full formal language has constants for collective and individual deontic admissibility, modalities for collective and individual agency, and modalities for collective and individual obligations. We classify its twenty-seven sublanguages in terms of their expressive power. This classification enables us to (...) investigate reducibility relations between collective deontic admissibility, collective agency, and collective obligations, on the one hand, and individual deontic admissibility, individual agency, and individual obligations, on the other. (shrink)

In this work we answer a long standing request for temporal embeddings of deontic STIT logics by introducing the multi-agent STIT logic TDS . The logic is based upon atemporal utilitarian STIT logic. Yet, the logic presented here will be neutral: instead of committing ourselves to utilitarian theories, we prove the logic TDS sound and complete with respect to relational frames not employing any utilitarian function. We demonstrate how these neutral frames can be transformed into utilitarian temporal frames, while preserving (...) validity. Last, we discuss problems that arise from employing binary utility functions in a temporal setting. (shrink)

No single moral theory can instruct us as to whether and to what extent we are confronted with legal loopholes, e.g. whether or not new legal rules should be added to the system in the criminal law field. This question on the primary rules of the law appears crucial for today’s debate on roboethics and still, goes beyond the expertise of robo-ethicists. On the other hand, attention should be drawn to the secondary rules of the law: The unpredictability of robotic (...) behaviour and the lack of data on the probability of events, their consequences and costs, make hard to determine the levels of risk and hence, the amount of insurance premiums and other mechanisms on which new forms of accountability for the behaviour of robots may hinge. By following Japanese thinking, the aim is to show why legally de-regulated, or special, zones for robotics, i.e. the secondary rules of the system, pave the way to understand what kind of primary rules we may want for our robots. (shrink)

This paper presents a short survey of recent developments in stit theories, with an emphasis on combinations of stit and deontic logic, and those of stit and epistemic logic.