The closer the approach to the central force behind any course of development, the fewer in number are the elements involved.  The rootage of literature in the spiritual nature and experience of the race is the fundamental fact not only in the history of this rich and splendid art, but in its relation to culture.  From this rootage flows the vitality which imparts immortality to its noblest products, and which supplies an educational element unrivalled in its enriching and enlarging quality.