[17] Man is a limited being. First of all, he is a being among other beings. His existence belongs to space and time. Thus, only a limited part of the total universe that can be given him at any one time. This limited part, however, is linked up with other parts in all directions both in time and in space. If our existence were so linked up with the things that every occurrence in the world were at the same time also an occurrence in us, the distinction between ourselves and the things would not exist. But then there would be no separate things at all for us. All occurrences would pass continuously one into the other. The cosmos would be a unity and a whole, complete in itself. The stream of events would nowhere be interrupted. It is owing to our limitations that a thing appears to us as single and separate when in truth it is not a separate thing at all. Nowhere, for example, is the single quality "red" to be found by itself in isolation. It is surrounded on all sides by other qualities to which it belongs, and without which it could not subsist. For us, however, it is necessary to isolate certain sections of the world and to consider them by themselves. Our eye can grasp only single colors one after another out of a manifold totality of color, and our understanding, can grasp only single concepts out of a connected conceptual system. This separating off is a subjective act, which is due to the fact that we are not identical with the world process, but are a single being among other beings.