6697. I have talked to spirits several times on this subject, when it was stated that anyone gifted with understanding may know from many considerations that a large number of planets exist and with people on them. For on rational grounds one may conclude that such large masses as the known planets, some of which are larger than Earth, are not empty masses, created merely to drift around the sun and shine for the benefit of one terrestrial world, but that they must have a function more note-worthy than any such as that. The person who believes, as everyone ought to believe, that the Divine created the universe with no other end in view than that the human race may come into being, and consequently heaven since the inhabitants of heaven come from among the human race, inevitably believes that there are people wherever any planet exists. The fact that the planets visible to our eyes because they are within the bounds of our solar system are other terrestrial worlds may be plainly recognized from the consideration that they are bodies consisting of earth-like material, since they reflect the light of the sun. Also those planets, just like ours, are propelled around the sun, producing - as they go - years and seasons of the year, which are spring, summer, autumn, and winter, together with variations created by climatic differences. Each, just like our world, also rotates on its axis, producing - as it spins round - days and times of day, which are morning, midday, evening, and night. In addition some of them have moons, which are called satellites and make regular circuits around their own globes, just as the moon does around ours. And because the planet Saturn is a very long way from the sun it also has a large lunar belt which provides that world with much light, even though it is reflected light. How can anyone who knows these things and thinks rationally ever speak of the planets as vacant masses?