The source-criticism2 of Diodorus XVI has been dominated by the principle of argument from detail. Thus, if two details in Diodorus' text are found to conflict, they are assumed to derive from different sources and, if similar, from the same source; and, where a fragment of an ancient historian is found to resemble a passage in Diodorus, that historian is assumed to be the source employed by Diodorus in that passage; finally, when a sufficient mosaic of such details is pieced (...) together, general divisions are drawn to embrace each separate detail. But this principle is of questionable value: for it implies the tacit assumption that Diodorus made no mistake in compressing or transcribing detail, added no colour himself, and could only have derived a given detail, described in a given manner, from the one ancient historian whose description of that detail is preserved. When one remembers that Diodorus is a careless and unintelligent compiler of a compendious narrative, who aimed like Ephorus at lending each book a unity, and that the fragments of the many historians whom Diodorus may have excerpted are very scanty, it is clear that this principle admits of a large margin of error. (shrink)