  The text of Prior’s Wellington address was not published until 1958 (in the journal Franciscan Studies, under the title ‘The Syntax of Time-Distinctions’). It was Prior’s 1956 John Locke lectures at Oxford and the ensuing book Time and Modality (published in 1957) that brought Prior’s discoveries in tense and modal logic before a wider audience. A number of logicians—notably Thomas, Geach, Lemmon, Meredith and Kripke—took an immediate interest in Priorean modal logic, in particular his Diodoran system and his system \(Q\), a multivalued logic admitting the existence of contingent beings. Less immediate attention was paid to his tense logic. The bibliography of the subject in Prior’s 1968 volume Papers on Time and Tense reveals that up until 1965 the only publications in the field were either by Prior himself or were reviews of his work (chiefly of Time and Modality). Yet a momentum was slowly gathering.