I have further supposed that no two worlds are alike in their developments of vitality, just as no two are alike as seen in the telescope, nor in their apparent physical characteristics. Yet, as in all the solar system there is an underlying unity of design, so I have supposed that "unity in diversity" is the law of vitality as well as of matter, and thus that the life in each of our sister-worlds is like some form or other of life to be found on Earth, just as the fact has been revealed to us by the spectroscope that the same metallic and gaseous elements as we find about us on Earth exist even in distant stars. Thus I have supposed that the life in other worlds is like what we find on earth, but that in each world there is a distinct development. In the apportionment of each such development to divers worlds, I have supposed that the physical constitution of each world, as far as we know it, affects the form of life upon it.
As to the theological question of God's dealings with the inhabitants of other worlds, I have hardly presumed to touch the subject. These things we can only know when we see no more as "in a glass darkly, but face to face"; and it seems to me that those who have ventured to speculate on it, as Kircher or Swedenborg, have exceeded propriety.
