The problem of writing and teaching Church History is being discussed in this journal and elsewhere, and it is obviously related to the more general problem treated by Mr. Harbison in the last number: the “meaning of history” and the writing et history. In the case of Ancient Church History it is especially difficult. “The problem of defining ‘Church’” may seem simpler because of the rigidity of the ecclesiastical organization developed in the early centuries and not broken by the year 800; but, given the fact that it did develop only gradually, how is the historian to treat gnosticism, Montanism, even Arianism? Is he always to say, “the Church was right”? If he says so, how is he to treat the elements of rightness in what came to be regarded as heresies? Or should he make value judgments other than tentative ones? To what extent is his history art and interpretation and to what extent is it science?