Event Semantics (ES) says that clauses in natural languages are descriptions of events. Why believe this? The answer cannot be that we use clauses to talk about events, or that events are important in ontology or psychology. Other sorts of things have the same properties, but no special role in semantics. The answer must be that this view helps to explain the semantics of natural languages. But then, what is it to explain the semantics of natural languages? Here there are many approaches, differing on, among other issues, whether natural languages are social and objective or individual and mental; whether the semantics delivers truth-values at contexts or just constraints on truth-evaluable thoughts; which inferences it should explain as formally provable, if any; and which if any grammatical patterns it should explain directly. The argument for ES will differ accordingly, as will the consequences, for ontology, psychology, or linguistics, of its endorsement.