The spontaneous tendency of the human mind is to place confidence in the indications of authorship, when there are any. On the cover and in the preface of the _Châtiments_, Victor Hugo is named as the author; therefore Victor Hugo is the author of the _Châtiments_. In such and such a picture gallery we see an unsigned picture whose frame has been furnished by the management with a tablet bearing the name of Leonardo da Vinci; therefore Leonardo da Vinci painted this picture. A poem with the title _Philomena_ is found under the name of Saint Bonaventura in M. Clément's _Extraits des poètes chrétiens_, in most editions of Saint Bonaventura's "works," and in a great number of mediæval manuscripts; therefore _Philomena_ was written by Saint Bonaventura, and "we may gather thence much precious knowledge of the very soul" of this holy man.[79] Vrain-Lucas offered to M. Chasles autographs of Vercingetorix, Cleopatra, and Saint Mary Magdalene, duly signed, and with the flourishes complete:[80] here, thought M. Chasles, are autographs of Vercingetorix, Cleopatra, and Saint Mary Magdalene. This is one of the most universal, and at the same time indestructible, forms of public credulity. Experience and reflection have shown the necessity of methodically checking these instinctive impulses of confiding trust. The autographs of Vercingetorix, Cleopatra, and Mary Magdalene had been manufactured by Vrain-Lucas. The _Philomena_, attributed by mediæval scribes now to Saint Bonaventura, now to Louis of Granada, now to John Hoveden, now to John Peckham, is perhaps by none of these authors, and certainly not by the first-named. Paintings in which there is not the least gleam of talent have, in the most celebrated galleries of Italy, been tricked out, without the least shadow of proof, with the glorious name of Leonardo. On the other hand, it is perfectly true that Victor Hugo is the author of the _Châtiments_. The conclusion is, that the most precise indications of authorship are never sufficient _by themselves_. They only afford a presumption, strong or weak--very strong, in general, where modern documents are concerned, often very weak in the case of ancient documents. False indications of authorship exist, some foisted upon insignificant works in order to enhance their value, some appended to works of merit in order to serve the reputation of a particular person, or to mystify posterity; and there are a hundred other motives which may easily be imagined, and of which a list has been drawn up:[81] the "pseudepigraphic" literature of antiquity and the middle ages is enormous. There are, in addition, documents which are forged from beginning to end; the forgers have naturally furnished them with very precise indications of their alleged authorship. Verification is therefore necessary. But how is it to be had? When the apparent authorship of a document is suspected, we use for its verification the same method which serves to fix, as far as possible, the origin of