As all material creation consists of out-births of things spiritual, the spiritual world being the world of causes, and the natural world that of effects, and as effects are the repositories of their causes, the natural world is the reflection of the spiritual. For this reason, from the beginning of things, the sun has stood out as a pre-eminent symbol of the things of God. Of all inanimate things it bears the closest correspondence to the Supreme Being, for what it is in the natural world the Supreme Being is in the Spiritual. Its central fire is the correspondence of the essence of the Divine Nature--DIVINE LOVE; its heat the correspondence of the heat flowing from Divine Love, which is Divine Goodness and all that that comprises; its light the correspondence of Divine Truth which is the light proceeding from Divine Wisdom; and the union of heat and light in its central essence forever symbolizes the union of the Divine Love and Wisdom resulting from that of the Divine Will and Understanding.God is the SUN from whose heat and light--His Love and Wisdom--proceed all that is spiritual, and through the spiritual, by the medium of the natural sun, all that is natural. The sun is supreme in all natural things, and its operations run through all in its own world, but the Divine SUN from which it derives its origin is supreme in all and operates through all, above and below. And as the natural sun is everywhere present in its own realm, and all things derive their life and grow in more or less perfect measure according to their forms and distances, so is the Supreme One omnipresent, filling both the spiritual and the natural world.
From a philosophical point of view, Leibniz's most interesting argument was that absolute space conflicted with what he called the principle of the identity of indiscernibles (PII). PII says that if two objects are indiscernible, then they are identical, i.e. they are really one and the same object. What does it mean to call two objects indiscernible? It means that no difference at all can be found between them--they have exactly the same attributes. So if PII is true, then any two genuinely distinct objects must differ in at least one of their attributes--otherwise they would be one, not two. PII is intuitively quite compelling. It certainly is not easy to find an example of two distinct objects that share all their attributes. Even two mass-produced factory goods will normally differ in innumerable ways, even if the differences cannot be detected with the naked eye.Leibniz asks us to imagine two different universes, both containing exactly the same objects. In Universe One, each object occupies a particular location in absolute space.In Universe Two, each object has been shifted to a different location in absolute space, two miles to the east (for example). There would be no way of telling these two universes apart. For we cannot observe the position of an object in absolute space, as Newton himself admitted. All we can observe are the positions of objects relative to each other, and these would remain unchanged--for all objects are shifted by the same amount. No observations or experiments could ever reveal whether we lived in universe One or Two.