The paper presents a logical framework for the representation of interactions between institutional agents, human agents and software agents. A case study is used to analyze how obligations on institutional agents are “propagated” to human and software agents, and how actions performed by these agents count as actions that satisfy the obligations imposed to institutional agents. It is shown that the relationship between the different kinds of obligations and actions can be represented in terms of the concept of “count as” (...) proposed by Searle, of role and of causality. The logical framework focus on those three concepts. (shrink)

This paper contains an analysis of performatives with special attention to performatives in the law. It deals with the possibility to recognise performativity by means of a grammatical-syntactic criterion, the self-verifying and norm-promulgating character of legal performatives, an analysis of the effects of performatives by means of causal logic, the different forms of performativity and a theory of promise-performatives.

This article proposes the use of temporal logic for an analysis of instrumentality inspired by the work of G.H. von Wright. The first part of the article contains the philosophical foundations. We discuss von Wright’s general theory of agency and his account of instrumentality. Moreover, we propose several refinements to this framework via rigorous definitions of the core notions involved. In the second part, we develop a logical system called Temporal Logic of Action and Expectations (TLAE). The logic is inspired (...) by a fragment of propositional dynamic logic based on indeterministic time. The system is proven to be weakly complete relative to its given semantics. We then employ TLAE to formalise and analyse the instrumentality relations defined in the first part of the paper. Last, we point out philosophical implications and possible extensions of our work. (shrink)

We present a logic of agency called LAE whose language includes propositional constants for actions and expectations. The logic is based on Von Wright’s theory of agency in general and his analysis of instrumentality in particular. An axiomatization of the logic, including an independence of agents axiom, is provided and soundness and completeness are shown with respect to its intended class of frames. The framework of LAE will allow us to formally define a manifold of concepts involved in agency theories, (...) including Von Wright’s four elementary forms of action, the notion of forbearance and notions of instrumentality that make reference to an agent’s expectations. (shrink)