The mood of thoughtful men, throughout the whole period, was one of deep unhappiness in regard to the affairs of this world, only rendered endurable by the hope of a better world hereafter. This unhappiness was a reflection of what was happening throughout Western Europe. The third century was a period of disaster, when the general level of well-being was sharply lowered. … In later times, until the Renaissance, men had no such simple happiness in the visible world, but turned their hopes to the unseen. Acragas is replaced in their love by Jerusalem the Golden. When earthly happiness at last returned, the intensity of longing for the other world grew gradually less.

Bertrand Russell, History of Western Philosop…, loc. 1196