What Made the Rabbanites Rabbinic?

The purpose of this essay is to open up a fundamental conversation about the concept of rabbinization, together with the adjective rabbinic, principally as a qualifier of Judaism. I shall follow these terms and concepts through the first millennium CE, from rabbis of the Roman period to early medieval Rabbanites. The title I have chosen refers to the Rabbanites, but the essay covers equally the earlier period, and it could equally have been entitled: What made the rabbis rabbinic? My purpose is not to answer these questions, but rather, to discuss and explain why they need to be asked.