DLW 163. The universe in general is divided into two worlds, the spiritual and the natural. In the spiritual world are angels and spirits, in the natural world men. In external appearance these two worlds are entirely alike, so alike that they cannot be distinguished; but as to internal appearance they are entirely unlike. The men themselves in the spiritual world, who are called angels and spirits, are spiritual, and, being spiritual, they think spiritually and speak spiritually. But the men of the natural world are natural, and therefore think naturally and speak naturally; and spiritual thought and speech have nothing in common with natural thought and speech. From this it is plain that these two worlds, the spiritual and the natural, are entirely distinct from each other, so that they can in no respect be together.

DLW 164. Now as these two worlds are so distinct, it is necessary that there should be two suns, one from which all spiritual things are, and another from which all natural things are. And as all spiritual things in their origin are living, and all natural things from their origin are dead, and these origins are suns, it follows that the one sun is living and the other dead; also, that the dead sun itself was created by the Lord through the living sun.

DLW 165. A dead sun was created to this end, that in outmosts all things may be fixed, settled, and constant, and thus there may be forms of existence which shall be permanent and durable. In this and in no other way is creation founded. The terraqueous globe, in which, upon which, and about which, things exist, is a kind of base and support; for it is the outmost work (ultimum opus), in which all things terminate, and upon which they rest. It is also a kind of matrix, out of which effects, which are ends of creation, are produced, as will be shown in what follows.

DLW 166. That all things were created by the Lord through the living sun, and nothing through the dead sun, can be seen from this, that what is living disposes what is dead in obedience to itself, and forms it for uses, which are its ends; but not the reverse. Only a person bereft of reason and who is ignorant of what life is, can think that all things are from nature, and that life even comes from nature. Nature cannot dispense life to anything, since nature in itself is wholly inert. For what is dead to act upon what is living, or for dead force to act upon living force, or, what is the same, for the natural to act upon the spiritual, is entirely contrary to order, therefore so to think is contrary to the light of sound reason. What is dead, that is, the natural, may indeed in many ways be perverted or changed by external accidents, but it cannot act upon life; on the contrary life acts into it, according to the induced change of form. It is the same with physical influx into the spiritual operations of the soul; this, it is known, does not occur, for it is not possible.