been accurately or approximately localised in space and time, and as much information as possible obtained about the author or authors. Here is a book: we wish to ascertain the origin of the information contained in it, that is, to be in a position to appreciate its value; is it enough to know that it was written in 1890, at Paris, by So-and-so? Perhaps So-and-so copied slavishly, without mentioning the fact, an earlier work, written in 1850. The responsible guarantor of the borrowed parts is not So-and-so, but the author of 1850. Plagiarism, it is true, is now rare, forbidden by the law, and considered dishonourable; formerly it was common, tolerated, and unpunished. Many historical documents, with every appearance of originality, are nothing but unavowed repetitions of earlier documents, and historians occasionally experience, in this connection, remarkable disillusions. Certain passages in Eginhard, a ninth-century chronicler, are borrowed from Suetonius: they have nothing to do with the history of the ninth century; how if the fact had not been discovered? An event is attested three times, by three chroniclers; but these three attestations, which agree so admirably, are really only one if it is ascertained that two of the three chroniclers copied the third, or that the three parallel accounts have been drawn from one and the same source. Pontifical letters and Imperial charters of the middle ages contain eloquent passages which must not be taken seriously; they are part of the official style, and were copied word for word from chancery formularies.
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