Religion, Society, and Nature! these are the three struggles of man. They constitute at the same time his three needs. He has need of a faith; hence the temple. He must create; hence the city. He must live; hence the plough and the ship. But these three solutions comprise three perpetual conflicts. The mysterious difficulty of life results from all three. Man strives with obstacles under the form of superstition, under the form of prejudice, and under the form of the elements.