This has seemed to many thinkers a philosophy too abstract and too remote from the world of experience. Hence the question arose whether it might not be possible to interpret nature in terms of mind without being compelled to take refuge in the abstractions of "absolutism." And pluralism is an attempt to solve the problem. LEIBNIZ REVIVED.--Leibniz' system of "monads," the nature of which will hardly have been forgotten, has been the model to which philosophers have looked in constructing their new system. And the "Monadology" may be taken as the type to which all modern attempts to construct a "pluralistic" philosophy more or less conform. The essence of "pluralism"--whether Leibnizian or other--lies in the proposition that there exists an indefinite variety of beings, some higher, some lower than ourselves. The pluralist agrees with the idealist in declaring that the essence of reality is _spirit_, but differs from him in declining to allow independent spirits to be absorbed by an "all-devouring Absolute." PLURALISM AND THEISM.--William James himself, in a work _A Pluralistic Universe_ (1909) outlined a philosophy of spirit radically opposed to "Absolute Idealism," which he subjects to a good deal of criticism. Another important work, written from a similar point of view, is Professor James Ward's _Pluralism and Theism_ (1911).[62] With regard to modern pluralism, the notable features are two. In the first place, it is a philosophy of _personality_, which it regards as the most fundamental form of reality; and also, that it is _theistic_ in a sense peculiar to itself. It believes in a God who may be termed the supreme monad, i.e. the head of a system of monads; but whose power may be said, in certain respects, to be limited. And indeed some such position seems to be the _logical_ conclusion that follows from the premises with which pluralists start, and also (we may add) from the facts of experience.[63] Pluralists unite in affirming that their God is (what they deny the idealistic Absolute to be) the God of the religious consciousness. James elaborates this thesis with his usual resourcefulness and skill. The controversy, however, is one into which it does not seem necessary for us to enter. Pluralism and idealism are or may be both definitely spiritual philosophies, and perhaps they appeal to different types of mind. We, at any rate, shall not undertake to judge between them. Both alike are preferable to dogmatic naturalism. CHAPTER XII SOME RECENT TENDENCIES IN SCIENCE SCIENTIFIC METHOD.--In the last chapter, attention was drawn to some important attempts to supply science with a sound philosophy of method, i.e. to give a critical account of those processes, logical and otherwise, which issue in what is called "scientific knowledge."