Abstract

Donald Davidson proposed an event ontology and considered events as entities to which people can refer and over which people can quantify. Davidson also proposed to interpret actions as events that are intentional under some descriptions. Recent years, some philosophers further developed his theory of action and extended their analysis to collective actions. It is an aim of this paper to contribute to this research program. In this paper, based on a four-dimensional event ontology, I propose an axiomatic theory for actions and agents and analyze collective actions and extended agents. This paper mainly investigates individual and collective actions that involve tools. This investigation also aims to give a metaphysical characterization of the ontological status of tools. In this investigation, it turns out that the four-dimensional ontology is a powerful framework to semantically describe temporally extended actions and collective actions. In two appendixes, I give a precise description of the proposed theories.