The very simplicity and nakedness of man's life in the primitive ages imply this advantage, at least, that they left him still but a sojourner in nature. When he was refreshed with food and sleep, he contemplated his journey again. He dwelt, as it were, in a tent in this world, and was either threading the valleys, or crossing the plains, or climbing the mountain-tops. But lo! men have become the tools of their tools. The man who independently plucked the fruits when he was hungry is become a farmer; and he stood under a tree for shelter, a housekeeper. We no longer camp as for a night, but have settled down on earth and forgotten heaven.... The best works of art are the expression of man's struggle to free himself from this condition, but the effect of our art is merely to make this low state comfortable and that higher state to be forgotten.