Reichenbach, Prior and hybrid tense logic (Q516424)

The contributions to tense logic of Hans Reichenbach and Arthur Prior are commonly presented as rivals. \textit{A. Prior} said of Reichenbach's scheme [Past, present and future. Oxford: Clarendon Press (1967; Zbl 0169.29802)] that it is at once too simple (in that each tense has one reference point but there are examples which require two) and too complicated, in that he missed the generalisation that reference points should be iterable indefinitely. The present paper deploys what is known in the study of tenses as a hybrid logic to combine the work of Prior and of Reichenbach elegantly to provide a structure which should be of interest also to students of tense in natural languages.