"It seems scarcely possible to account for this attitude except by means of the following explanation: because their own civilization hardly goes any further back than the Graeco-Roman period and derives for the most part from it, Westerners are led to believe that it must have been the same in every other case, and they have difficulty in conceiving of the existence of entirely different and far more ancient civilizations. It might be said that they are mentally incapable of crossing the Mediterranean."