We show a property of strings is expressible in the two-variable fragment of rst-order logic if and only if it is expressible by both a 2 and a 2 sentence. We thereby establish: where UTL stands for the string properties expressible in the temporal logic withèventually in the future' andèventually in the past' as the only temporal operators and UL stands for the class of unambiguous languages. ...

Abstract Processes produce changes: rivers erode their banks and thunderstorms cause floods. If I am right that organisms are a kind of process, then the causally efficacious behaviours also examples processes producing change. In this paper shall try to articulate view how we should think causation within broadly processual ontology living world. Specifically, argue causation, at least in cent...