According to the view of things above adverted to, the different stages in the history of our race are not successive only, but are also co-existent and co-extensive with each other. Just as in a block of marble, there is contained, not one only, but every possible statue, though, of the whole number, only one at a time can be made evident to our senses; so, in a given region of space, any number of worlds can co-exist, each with its own population conscious of only that world, or set of phenomena, to which their ego is attuned.