Now a system of this kind seems to exhibit all the defects of Pluralism with certain superadded difficulties of its own. We might reasonably object that experience presents us with no example of a genuine system in which all the elements are actually independent. The nearest approach to such a case seems to be found in the classes of an “artificial classification,” in which things standing in no relation of interaction among themselves are put together by us because it is convenient for some extraneous purpose of our own to comprehend them under a single point of view. But, apart from the impossibility of constructing a classification which shall be more than relatively artificial, such a mere aggregate or collection is not a real system. In a true system, as distinct from a mere collection, the principle of unity has always some sort of significance for the members of the system themselves. It represents, at the least, the way in which the members interact with each other. (Thus, to take an extreme case, the serial arrangement of cutting implements in a museum, from the flaked stone of the Palæolithic age to the latest specimen of Sheffield cutlery, is more than a merely “artificial” classification, precisely because it is more than a mere grouping of separate objects according to their likeness and unlikeness; it represents the stages of a continuous historical evolution.) Now, it is essential to Monadism that the monads, because ultimately independent, shall only seem to interact. They appear to form a single world with a history in which each distinct state of each monad is a stage. But really, while the successive states of the individual monad are, what they seem to be, a connected process of development, the various processes do not make up a single-world history at all. They only seem to do so by an inevitable illusion. Hence the unity of the whole system must after all be not only ideal, but, strictly speaking, imaginary. Similar difficulties arise from the ambiguous position accorded to God in the scheme. If the “pre-established harmony” between the states of the individual monads were simply due to a creative fiat of God, we should be thrown back upon mere arbitrary chance as the reason, if it can be called a reason, why existence is not a chaos. But if God’s choice to create this scheme of things rather than another was due to the superior attraction which a world with at least the appearance of connected system had for the divine intellect, then it is ultimately in the constitution of the divine mind that we have to find the reason why the alternative possibilities before creation were what they were;[58] and again, why just this one was preferred to all the rest. And thus the monads cease to be any longer ultimate and independent, and the nature of God becomes the single determinate ground of all reality.