Simultaneous Events and the "Once-Only" Effect

Abstract. Some events recur, and some happen only once. Galton refers to the latter as "once-only" events [1]. In a first-order logic of events that makes a type-token distinction, the possibility of concurrent occurrences of the same event renders the characterization of the intuitive once-onliness not very intuitive. In particular, the paradigmatic case of the nth occurrence of a recurring event is shown to be not necessarily once-only. Counter-examples give rise to a classification of events based on the temporal relations among their occurrences. The problematic cases turn out to be those events that involve an indefinite individual; we call these indefinitelyspecified events. We consider two options. The first is to restrict our event ontology, as has been implicitly done in most logics of events, to events that are definitelyspecified. The second is to admit all sorts of events into our ontology and distinguish those that are definitely-specified from those that are not...

• Type: Conference
• Year: 2006
• Where: FOIS
• Authors: Haythem O. Ismail
• Keywords: First-order Logic, FOIS 2006, FOIS 2008, Indefinite Individual, Indefinitelyspecified Events