Of course the problem would alter its character if God were conceived as another expression for the total system of Reality. The doctrine of Occasionalism would then become simply a statement of the view that no two things are really independent, and that it is in virtue of their inclusion in a larger systematic whole that what we call separate things can influence each other. But, in spite of numerous passing utterances which point to this view, it is quite certain that Occasionalism was seriously intended by its authors as a solution of the problem of Causality on strictly traditional theistic lines. (2) A second defect of the doctrine lies in the failure of its originators to extend it to _all_ cases of causal relation. It is a mere prejudice when Geulincx and Malebranche allow themselves to assume that the sequence of physical change on preceding physical change, or mental change on preceding mental change, is more self-explanatory than the sequence of a mental change on a physical. In both cases we can ascertain that one state definitely follows a previous one; in neither can we answer the ultimately unmeaning question, by what machinery this sequence is brought about. For any answer must obviously consist in the interpolation of an intermediate link, and with regard to the production of this intermediate link the same question arises, and thus we come to the indefinite regress, the invariable indication that we have been asking an unmeaning question. (_b_) _The Pre-established Harmony._ More philosophical was the attempt of Leibnitz to reconcile Pluralism with the apparent interaction of things. According to Leibnitz, every ultimately real thing or monad is a self-contained whole; it contains, therefore, in itself the ground of the sequence of its own states. Hence there can be no real origination of change in one monad by the occurrence of change in another. The life of every monad must consist purely in the development of its own internal nature. As Leibnitz phrases it, there are no windows in the monads through which states and qualities can fly from one to another. Yet some account must be taken of the apparent fact that, since the world of experience is not a chaos, the changes in one thing seem to be connected by definite law with the changes in others.