The objection which it is necessary to express concerning Materialism as a complete system is based not on its assertions but on its negations. In so far as it makes positive assertions, embodying the result of scientific discovery and even of scientific speculation based thereupon, there is no fault to find with it; but when, on the strength of that, it sets up to be a philosophy of the universe--all inclusive, therefore, and shutting out a number of truths otherwise perceived, or which appeal to other faculties, or which are equally true and are not really contradictory of legitimately materialistic statements--then it is that its insufficiency and narrowness have to be displayed. As Professor Ritchie said:--"The 'legitimate materialism of the sciences' simply means temporary and convenient abstraction from the cognitive conditions under which there are 'facts' or 'objects' for us at all; it is 'dogmatic materialism' which is metaphysics of the bad sort." It will be probably instructive, and it may be sufficient, if I show that two great leaders in scientific thought (one the greatest of all men of science who have yet lived), though well aware of much that could be said positively on the materialistic side, and very willing to admit or even to extend the province of science or exact knowledge to the uttermost, yet were very far from being philosophic materialists or from imagining that other modes of regarding the universe were thereby excluded. Great leaders of thought, in fact, are not accustomed to take a narrow view of existence, or to suppose that one mode of regarding it, or one set of formulæ expressing it, can possibly be sufficient and complete. Even a sheet of paper has two sides: a terrestrial globe presents different aspects from different points of view; a crystal has a variety of facets; and the totality of existence is not likely to be more simple than any of these--is not likely to be readily expressible in any form of words, or to be thoroughly conceivable by any human mind. It may be well to remember that Sir Isaac Newton was a Theist of the most pronounced and thorough conviction, although he had a great deal to do with the reduction of the major Cosmos to mechanics, _i.e._, with its explanation by the elaborated machinery of simple forces; and he conceived it possible that, in the progress of science, this process of reduction to mechanics would continue till it embraced nearly all the phenomena of nature. (See extract below.) That, indeed, has been the effort of science ever since, and therein lies the legitimate basis for materialistic statements, though not for a materialistic philosophy. The following sound remarks concerning Newton are taken from Huxley's "Hume," p. 246:--