Neither poem could have been written if there had not been a long antecedent history, rich in every kind and quality of human contact with the world, and of the working out of the forces which are in every human soul.

These two forms of activity represent in a general way what men have learned about themselves and their surroundings; and, taken together, they constitute the material out of which interpretations and explanations of human life have been made.
These explanations vary according to the genius, the environment, and the history of races but in every case they represent the very soul of race life, for they are the spiritual forms in which that life has expressed itself.

Other forms of race activity, however valuable or beautiful, are lost in the passage of time, or are taken up and absorbed, and so part with their separate and individual existence; but the quintessence of experience and thought expressed in great works of art is gathered up and preserved, as Milton said, for "a life beyond life." Now, it is upon this imperishable food which the past has stored up through the genius of great artists that later generations feed and nourish themselves.

It is through intimate contact with these fundamental conceptions, worked out with such infinite pain and patience, that the individual experience is broadened to include the experience of the race.

This contact is the mystery as it is the source of culture.