It belongs to the investigation of authorship to discover, as far as possible, the sources utilised by the authors of documents.
The problem thus presented to us has some resemblance to that of the restoration of texts of which we have already spoken. In both cases we proceed on the assumption that identical readings have a common source: a number of different scribes, in transcribing a text, will not make exactly the same mistakes in exactly the same places; a number of different writers, relating the same facts, will not have viewed them from exactly the same standpoint, nor will they say the same things in exactly the same language. The great complexity of historical events makes it extremely improbable that two independent observers should narrate them in the same manner. We endeavour to group the documents into families in the same way as we make families of manuscripts. Similarly, we are enabled in the result to draw up genealogical tables. The examiners who correct the compositions of candidates for the bachelor's degree sometimes notice that the papers of two candidates who sat next each other bear a family likeness. If they have a mind to find out which is derived from the other, they have no difficulty in doing so, in spite of the petty artifices (slight modifications, expansions, abstracts, additions, suppressions, transpositions) which the plagiarist multiplies in order to throw suspicion off the scent The two guilty ones are sufficiently betrayed by their common errors; the more culpable of the two is detected by the slips he will have made, and especially by the errors in his own papers which are due to peculiarities in those of his accommodating friend. Similarly when two ancient documents are in question: when the author of one has copied directly from the other, the filiation is generally easy to establish; the plagiarist, whether he abridges or expands, nearly always betrays himself sooner or later.[86]
When there are three documents in a family their mutual relationships are sometimes harder to specify. Let A, B, and C be the documents. Suppose A is the common source: perhaps B and C copied it independently; perhaps C only knew A through the medium of B, or B knew it only through C. If B and C have abridged the common source in different ways, they are evidently independent. When B depends on C, or vice versâ, we have the simplest case, treated in the preceding paragraph. But suppose the author of C combined A and B, while B had already used A: the genealogy begins to get complicated. It is more complicated still when there are four, five, or more documents in a family, for the number of possible combinations increases with great rapidity. However, if too many intermediate links have not been lost, criticism succeeds in disentangling the relationships by persistent and ingenious applications of the method of repeated comparisons. Modern scholars (Krusch, for example, who has made a speciality of Merovingian hagiography) have recently constructed, by the use of this method, precise genealogies of the utmost solidity.[87] The results of the critical investigation of authorship, as applied to the filiation of documents, are of two kinds. Firstly, lost documents are reconstructed. Suppose two chroniclers, B and C, have used, each in his own way, a common source X, which has now disappeared. We may form an idea of X by piecing together the fragments of it which occur imbedded in B and C, just as we form an idea of a lost manuscript by comparing the partial copies of it which have been preserved. On the other hand, criticism destroys the authority of a host of "authentic" documents—that is, documents which no one suspects of having been falsified—by showing that they are derivative, that they are worth whatever their sources may be worth, and that, when they embellish their sources with imaginary details and rhetorical flourishes, they are worth just nothing at all. In Germany and England editors of documents have introduced the excellent system of printing borrowed passages in small characters, and original passages whose source is unknown in larger characters. Thanks to this system it is possible to see at a glance that celebrated chronicles, which are often (very wrongly) quoted, are mere compilations, of no value in themselves: thus the Flores historiarum of the self-styled Matthew of Westminster, perhaps the most popular of the English mediæval chronicles, are almost entirely taken from original works by Wendover and Matthew of Paris.[88]
IV. The critical investigation of authorship saves historians from huge blunders. Its results are striking. By eliminating spurious documents, by detecting false ascriptions, by determining the conditions of production of documents which had been defaced by time, and by connecting them with their sources,[89] it has rendered services of such magnitude that to-day it is regarded as having a special right to the name of "criticism." It is usual to say of an historian that he "fails in criticism" when he neglects to distinguish between documents, when he never mistrusts traditional ascriptions, and when he accepts, as if afraid to lose a single one, all the pieces of information, ancient or modern, good or bad, which come to him, from whatever quarter.[90]
This view is perfectly just. We must not, however, be satisfied with this form of criticism, and we must not abuse it.
We must not abuse it. The extreme of distrust, in these matters, is almost as mischievous as the extreme of credulity. Père Hardouin, who attributed the works of Vergil and Horace to mediæval monks, was every whit as ridiculous as the victim of Vrain-Lucas. It is an abuse of the methods of this species of criticism to apply them, as has been done, indiscriminately, for the mere pleasure of it. The bunglers who have used this species of criticism to brand as spurious perfectly genuine documents, such as the writings of Hroswitha, the Ligurinus, and the bull Unam Sanctam,[91] or to establish imaginary filiations between certain annals, on the strength of superficial indications, would have discredited criticism before now if that had been possible. It is praiseworthy, certainly, to react against those who never raise a doubt about the authorship of a document; but it is carrying the reaction too far to take an exclusive interest in periods of history which depend on documents of uncertain authorship. The only reason why the documents of modern and contemporary history are found less interesting than those of antiquity and the early middle ages, is that the identity which nearly always obtains between their apparent and their real authorship leaves no room for those knotty problems of attribution in which the virtuosi of criticism are accustomed to display their skill.[92]
Nor must we be content with it. The critical investigation of authorship, like textual criticism, is preparatory, and its results negative. Its final aim and crowning achievement is to get rid of documents which are not documents, and which would have misled us; that is all. "It teaches us not to use bad documents; it does not teach us how to turn good ones to account."[93] It is not the whole of "historical criticism;" it is only one stone in the edifice.[94]
CHAPTER IV
CRITICAL CLASSIFICATION OF SOURCES
By the help of the preceding operations the documents, all the documents, let us suppose, of a given class, or relating to a given subject, have been found. We know where they are; the text of each has been restored, if necessary, and each has been critically examined in respect of authorship. We know where they have come from. It remains to combine and classify the materials thus verified. This is the last of the operations which may be called preparatory to the work of higher (or internal) criticism and construction.