But a work may happen to want this kind of evidence, and yet, on other grounds, it may possess a valid claim to genuineness. In fact, almost all the existing remains of ancient literature are abundantly authenticated by the numerous and explicit quotations from them, or descriptions of them, that occur in other works. And there are very few books that do not contain some direct or some indirect allusions to other works: so it is that the remains of ancient literature, taken as a mass, contains within itself the proof of the authenticity of each part.
The nature of the case gives to this body of references a pyramidal form. In the most remote age it is, of course, small in amount; in the next age it becomes much more ample and substantial; and in later periods, it spreads itself over the entire surface of literature.
The literature of the Greeks was national and original; they borrowed from their neighbours less in poetry, philosophy, and history, than in religion, or the arts: their early writers were not, in the modern sense of the term, men of learning; their works were composed at the impulse of genius, and of the moving spirit of the times. The habit of literary allusion and quotation had not then been formed, nor indeed was it congruous with this order of intellectual production; and yet the early Greek writers contain mutual references, which, if not numerous, are sufficient to establish and ascertain, in most instances, the genuineness of each.
The second period of Greek literature, dating from the times of Alexander, and reaching down to the overthrow of the Greek national independence by the Romans, was, in the natural order of things, an era of learning, of criticism, and of imitation. The writers of this period, therefore, abound with references of all kinds to their predecessors and contemporaries. A second age of literature holds up a mirror of the first. Erudition, amplitude, comprehension, method, labour, take the place of spontaneous effort, and of intuitive taste. Commentators, compilers, and collectors abound; and the writers of such an age seem to perform the functions of caryatides in the temple of learning; as if their only business was to sustain the pediment which chiefly attracts the admiration of spectators. Among writers of this class, therefore, we are to look for a copious harvest of quotations; and in their pages we shall rarely fail to meet with evidence bearing upon any question of the genuineness of an ancient writer.
The Romans borrowed everything but energy of character and practical good sense, from the Greeks. Their literature, from the first, was of a derived character; their writers added learning to what might be their native genius; and their works reflect the literature of their masters. Sufficiently ample allusions, therefore, to the most celebrated of the Greek authors, as well as to those of their countrymen, are found scattered throughout the Latin classics.
Both the Greek and Latin writers of later ages were well acquainted with the literature of brighter times; and they have left in their works ample means for bringing down the chain of references to the time of the decline of learning in Europe—to that time up to which we have already traced the history of existing manuscripts; so that the two lines of evidence unite about midway between the fifth and the fifteenth centuries.
The nature, extent, and validity of the evidence that may be derived from the mutual references of authors, will be best exhibited by a classification of its several kinds under the following heads:—
1. Literal quotations, whether the author cited is named or not. Such quotations serve the double purpose of proving the existence of the work quoted in the time of the writer who makes the reference, and of identifying, and sometimes even of correcting, the extant text. If, for example, in subsequent writers, we find only a dozen or twenty sentences, taken from different parts of an earlier work, the verbal coincidence is sufficient to prove that the work, such as we now find it, is the same as that quoted. When such quotations are numerous and exact, they afford the best means, either of restoring the genuine reading of authors, or of judging of the comparative purity of different manuscripts. For frequently these quotations seem to have suffered less in the course of transcription than either the other parts of the work in which they are found, or than that from which they are taken. The reason of this difference may readily be imagined:—either the author himself quoted from a copy purer than any that are now extant; or the transcriber, meeting with a passage which he remembered to belong to a well-known work, consulted the original, of which he had a good copy, and the very circumstance of doing so would naturally induce somewhat more of care than in ordinary transcription.
2. Incidental allusions are often met with, either to the words or to the sense of an author, sufficiently obvious to prove that the one writer was known to the other; and yet they are too incidental and remote to be regarded as an interpolation. In questions of apparent difficulty, such accidental references may be conclusive in proof of the existence of a work at a certain time. Among the ancient historians, there are instances in which two writers, who do not mention each other, narrate the same facts with so many coincidences of method, or of details, embellishments, or reflections, as to make it certain either that both narratives were derived from the same source; or that the one was copied from the other. And if the one narrative has altogether the air of originality, and is in accordance with the writer’s style and spirit, the other writer must be held to be the quoting party, and therefore he establishes the prior existence of the work from which he has borrowed.
3. Nearly every one of the principal authors of antiquity has been explicitly mentioned, or criticised, or described, by later writers. Lists of their works have been given, with summaries of their contents; or they have been made the subjects of connected commentaries, by means of which the mass of the original work may be identified, and collated, with existing copies. Books of this secondary class are usually fraught with references to the entire circle of literature that was extant in the writer’s time. There are also extant several works containing the lives of ancient authors, with accurate lists of their works. These biographical pieces, while they have on one hand afforded a security against the production of spurious works, on the other hand have given occasion to such attempts; for if some treatise, known to have been written by a celebrated author, was believed to have perished, an opportunity was presented for composing one which should correspond with the description given of it. But such spurious works must always be deficient in positive evidence, nor will they fail to betray the imposition by some glaring inconsistencies in style, or in matter. The lives of statesmen and warriors often contain such allusions to the writers of the same age, as suffice to prove the time when they flourished. All the information we possess on this head is, in many instances, derived from allusions of this sort.