To be sure, like many monuments of ancient literature in general and most of the Old Testament books in particular, Genesis is the result of collective writing. Literary critics have described the composite character of its authorship and the long process of its compilation. They have isolated, analyzed, dated, and characterized as its literary sources, various sequences of narratives and cycles of traditions. They have even recognized that each of these sources was in turn the result of editorial work, either written or oral, done by individuals or schools of storytellers and poets who represented specific and sometimes contradictory points of view concerning history, psychology, sociology, ethics, and religious beliefs or practices. Likewise, more recent students have observed that the materials used by these various authors or editors offer a remarkably wide range of literary forms, such as myths, legends, fragments of individual, tribal, and national biography or lore, excerpts from genealogies, quotations of ancient falk songs, ditties, proverbs, oracles, and local sayings of aetiological interest. This analytical work is most valuable, for it enables the historian to reconstruct with a relative degree of certainty the chronological development of the religion of Israel over a period of a thousand years or more. In many ways, Genesis resembles a mediaeval church which was built on the foundations of a Gallo-Roman temple dedicated to the goddess Isis: the stones of its crypt reveal the signs of Byzantine art, the columns of its apse are in pure Romanesque, the vaulting of its transept and nave show the grace of middle Gothic, its Western rose window displays the wealth of the Flamboyant, and even one of its portals, which fell during the XVIIIth century, has been rebuilt in the Baroque style. In spite of its composite origin, this edifice is not an architectural monstrosity. It possesses a distinctive personality, it offers an esthetic message which is wholly its own, and it must be interpreted and understood as a single work of art. Mutatis mutandis, the book of Genesis as it exists today may represent several schools of widely different or conflicting conceptions of ethics and religion. Nevertheless, its final editor has succeeded in presenting a relatively homogeneous document, with a singleness of purpose, and a dominant message which overshadows the discrepancies of details. Whatever sources may have been incorporated within its frame, whatever traditions may have been preserved in its chapters, whatever historical, psychological, sociological, moral, and religious points of view may still appear in its pages, Genesis exists as a completed masterpiece, polished and rounded, whose unity of theme and plan offers a striking contrast with the loosely connected, ill-digested, and sometimes chaotic agglutination of literary deposits which are found in other sections of the Hexateuch.