In judging Diodorus, then, one must judge him as a Roman of the first century B.C., not as a European of the twentieth century A.D. And if we bear this in mind, we shall find, after scanning his pages, that Diodorus was by no means marked among his fellows by simple credulity of the unquestioning type which accepts whatever is told it without subjecting it to criticism. Diodorus, to be sure, tells us fabulous tales as to the origin of the world and the creation of its various peoples; but he explicitly forewarns us that he tells these tales, not as matters of his own belief, but in order to make an historical record of the opinions current among the different nations themselves as to their own origin.
These tales seem to us fabulous, grotesque, absurd; but we have no reason to doubt that many of them seemed equally mythical to Diodorus himself; and modern criticism should not forget that there is one other myth tale of the creation of the world and the origin of a particular race, which, had Diodorus known it, he would doubtless have narrated with the rest, and viewed with the same scepticism which he shows towards the others, as being fabulous, grotesque, and absurd, but which would have been accepted by the critics of all Christendom, in every age prior to our own, as the authentic historical record of the actual creation of the earth, and as the true account of its chosen people.
In a word, modern criticism should bear in mind, when reproaching Diodorus and others like him for their credulity, that the accepted faith of nineteenth-century Europe would have seemed to Diodorus as absurd and fabulous and mythical as any tale which he has to tell us can seem to the twentieth-century critic.
And as to the mistakes of Diodorus in the more strictly historical portions of his narrative, these also must be viewed with a certain toleration by every candid critic when he reflects upon the vast preponderance of those cases in which the records of Diodorus are worthy of the fullest credence. In considering these matters, it is very easy, indeed, to generate myths that befog our view of the true status of an ancient author. Thus, for example, it was once traditional to regard Thucydides as the most candid, just, and impartial historian who has ever lived; but it can hardly be in doubt that the real reason why this estimate has grown up about the name of Thucydides is the fact that, as Professor Mahaffy points out, Thucydides is the sole authority for the history of most of the period of which he treats. It has even been admitted by Müller that in the early portion of the first chapter of Thucydides, where he treats on Grecian history in general, and up to the Peloponnesian War, he does not manifest the same impartiality which distinguishes him in the later portions of his narrative. But it is precisely in this earlier chapter that Thucydides deals with events that are recorded by other historians. It is here, and for the most part here alone, that his story can be checked by data from other authors. Could we similarly check the story of the Peloponnesian War in general, it can hardly be in doubt that we should come across at least some discrepancies which would have tended materially to modify the almost idolatrous estimate of Thucydides that came to be, and long continued to be, unquestionably associated with his name.
Making the application of this thought to Diodorus, it is evident at once that the historian of a limited period of antiquity lays himself open to no such range of comparison as he who undertakes to write the history of the entire world. In the very nature of the case, such a writer pits himself against the whole company of specialists; and, after all, it is hardly surprising, should it be susceptible of proof, that in several, or all, fields there are specialists whose accuracy excels the accuracy of Diodorus in each particular field. Surely the comprehensiveness of his task must count for something in the estimate, and, when all this is taken into consideration, it may fairly be repeated that the general estimate of modern criticism has done but scant justice to the author of the first attempt ever made to write a complete and comprehensive history of the world.
Moreover, it must not be forgotten that in his use of authorities Diodorus sometimes showed a selective judgment that is entitled to the fullest praise. A notable instance is found in his treatment of that period of Grecian history following the Peloponnesian War, when the Spartans and the Thebans were contending for supremacy. It was treated by Xenophon in his Hellenica, and as Xenophon was actual witness of many of the events which he describes, the presumption would be that his authority for the period might be considered incontestable. But in point of fact, Xenophon, philosopher though he was and pupil of Socrates, was not above the influence of personal prejudice. He was a friend of Agesilaus, and his admiration for that hero, as well as his fondness for the Spartans in general, prejudiced his narrative to such an extent that he did very scant justice to the merits of the great Epaminondas. Indeed, were we to trust to Xenophon alone, the world never would have had in later times anything like a just appreciation of the merits of the great Theban, and since Xenophon’s account of this period is the only contemporary one that has been preserved, it was a rare chance, indeed, that preserved to posterity a just appreciation of the greatest of the Thebans, whom some critics are wont to consider the greatest of all the Greeks; and it is Diodorus whom we must thank for doing this historic justice to a great man whose merits might otherwise have been obscured by the personal prejudice of a contemporary historian.
Diodorus, in treating this period, chose as his authority, not Xenophon, but Aphorus. Just how he came to this decision is not known; it suffices that the decision was a good one. None but a prejudiced critic can doubt that in many other cases his judgment was equally perspicuous in selecting among divergent accounts the one of greatest verisimilitude.
A part of the relative neglect which has fallen to the lot of Diodorus may be ascribed to the manner of his handling. He threw his work into the form of annals, in which a chronological idea was predominant. He gives the history of a nation in a given year, and then turns aside to other nations, to follow the fortunes of each in turn over the same period. Necessarily, under such a treatment, the whole plan lacks continuity. One must break from one subject to another, must turn from Assyria to Egypt, from Greece to Rome, in order to follow the story through constantly broken chapters. Naturally, under such treatment, the reader’s interest flags. From a popular standpoint, such a treatment is clearly a mistake.
The plan of Herodotus, which took up the story of each nation, and carried it through a long period uninterruptedly, has many advantages; is infinitely more artistic. It is chiefly due to this treatment, rather than the actual phrasing of his story, that Herodotus has gained so much more universal fame than Diodorus; for in those parts of his history in which he does attempt a continuous narrative, Diodorus shows much skill as a story-teller. In the earlier portion of his work, that portion which, fortunately, has in the main been preserved to us, when dealing with what he regards as the fabulous history of the nations prior to the establishment of a fixed chronology, his narrative runs on continuously, suggesting in many ways that of the Father of History. It was so with his treatment of early Egypt, and with his even more interesting history of ancient Assyria. These parts alone of his work serve to make him one of the most important authors of antiquity whose writings have been preserved to us, and we shall have occasion to draw largely upon him for the history of this period.