διά as a polysemous preposition in Early Byzantine Greek : ‘Dead ends’ and other uses in the Qurrah archive (VIII AD)

In this article, I offer a systematic description of the various uses of the preposition διά in the Early Byzantine archive of Qurrah ibn Sharik (VIII AD), an archive in which the preposition is attested remarkably frequently. Functionally, the use of διά is reminiscent of the Classical period, in that various older uses are attested that no longer occur in Modern Greek (such as PATH, INTERMEDIARY, and INSTRUMENT). However, there are also various innovative uses that are attested neither in the Classical nor in the Modern period (such as AGENT, SOURCE, and OPPONENT). The occurrence of these ‘dead ends’ shows that the functional development of prepositions from Classical to Modern Greek should not be thought of as linear