The arts and the inventions, the knowledge and the books, which suddenly became vital at the time of the Renaissance, had long lain neglected on the shores of the Dead Sea which we call the Middle Ages.

It was not their discovery which caused the Renaissance.

But it was the intellectual energy, the spontaneous outburst of intelligence, which enabled mankind at that moment to make use of them.

The force then generated still continues, vital and expansive, in the spirit of the modern world.
How was it, then, that at a certain period, about fourteen centuries after Christ, to speak roughly, the intellect of the Western races awoke as it were from slumber and began once more to be active?
That is a question which we can but imperfectly answer.

The mystery of organic life defeats analysis; whether the subject of our inquiry be a germ-cell, or a phenomenon so complex as the commencement of a new religion, or the origination of a new disease, or a new phase in civilization, it is alike impossible to do more than to state the conditions under which the fresh growth begins, and to point out what are its manifestations.