In the previous chapter, we pointed out that the term “event structure” is now widely used to refer to the lexical semantic representation which determines argument realization. This term reflects a consensus that such representations encode properties of events. Nonetheless, there are fundamental differences among the representations that have been proposed. Many of these stem from alternative hypotheses about which semantic properties of events influence argument realization and, thus, are central to the organization of event structure. Our goal in this chapter is to delineate theories concerning these semantic properties. Semantic properties of events are shown to be relevant for the organization of event structure to the extent that the subclasses of events which they define share identifiable grammatical properties. We present a discussion of these properties under the rubric of theories of event conceptualization since a hypothesis about what facets of an event are grammatically relevant is a hypothesis about how language users conceptualize happenings in the world for linguistic encoding. It is reasonable to assume that those properties of events that are grammatically relevant are also cognitively salient in some pretheoretically intuitive way (B. Levin and Pinker 1991) and that such properties should find their way into semantic representations.

As we review in this chapter, broadly speaking, three ways of conceptualizing events have been proposed to be grammatically relevant; each focuses on a distinct cognitively salient facet of events. The first, the localist approach, highlights the notions of motion and location. The second, the aspectual approach, suggests that the temporal properties of events, including their mereological (part–whole) structure, are central.