Human societies have ever what is called in theatres "un troisième dessous," and the social soil is everywhere undermined, here for good and there for evil. These works are upon one another; there are upper mines and lower mines, and there is a top and bottom in this obscure sub-soil, which at times gives way beneath the weight of civilization, and which our indifference and carelessness trample under foot. The Encyclopædia was in the last century an almost open mine, and the darkness, that gloomy brooder of primitive Christianity, only awaited an occasion to explode beneath the Cæsars and inundate the human race with light. For in the sacred darkness there is latent light, and the volcanoes are full of a shadow which is capable of flashing, and all lava begins by being night. The catacombs in which the first Mass was read were not merely the cellar of Rome but also the vault of the world. There are all sorts of excavations beneath the social building, that marvel complicated by a hovel; there is the religious mine, the philosophic mine, the political mine, the social economic mine, and the revolutionary mine. One man picks with the idea, another with figure, another with auger, and they call to and answer each other from the catacombs. Utopias move in subterranean passages and ramify in all directions; they meet there at times and fraternize. Jean Jacques lends his pick to Diogenes, who lends him his lantern in turn; at times, though, they fight, and Calvin clutches Socinus by the hair. But nothing arrests or interrupts the tension of all their energies toward the object, and the vast simultaneous energy, which comes and goes, ascends, descends, and reascends, in the obscurity, and which slowly substitutes top for bottom and inside for out; it is an immense and unknown ant-heap. Society hardly suspects this excavation, which leaves no traces on its surface and yet changes its insides; and there are as many different works and varying extractions as there are subterranean tiers. What issues from all these deep excavations? The future.