to see how breaks in the continuity of being can be established, when every living plant confutes the absolute difference between the organic and inorganic, and, by the very fact of living, turns the latter into the former; and it is difficult to deny the continuity of “mind and matter,” when every human being is relating himself to the outer world in all his thoughts and actions.  And religion is the very last form of thought which could profit from such a proof of absolute distinctions, were it possible.  In fact, as we have seen, religion, in so far as it demands a perfect and absolute being as the object of worship, is vitally concerned in maintaining the unity of the world.  It must assume that matter, in its degree, reveals the same principle which, in a higher form, manifests itself in spirit.

But closer investigation will show that the real ground for such apprehension does not lie in the continuity of existence, which evolution implies; for religion itself postulates the same thing.  The apprehension springs, rather, from the idea that the continuity asserted by evolution, is obtained by resolving the higher forms of existence into the lower.  It is believed that, if the application of development to facts were successfully carried out, the organic would be shown to be nothing but complex inorganic forces, mental life nothing but a physiological process, and religion, morality, and art, nothing but products of the highly complex motion of highly complex aggregates of physical atoms.

It seems to me quite natural that science should be regarded as tending towards such a materialistic conclusion.  This is the view which many scientific investigators have themselves taken of their work; and some of their philosophical exponents, notably Mr. Herbert Spencer, have, with more or less inconsistency, interpreted the idea of evolution in this manner.  But, it may be well to bear in mind that science is generally far more successful in employing its constructive ideas, than it is in rendering an account of them.  In fact, it is not its business to examine its categories:  that task properly belongs to philosophy, and it is not a superfluous one.  But, so long as the employment of the categories in the special province of a particular science yields valid results, scientific explorers and those who attach, and rightly attach, so much value to their discoveries, are very unwilling to believe that these categories are not valid universally.  The warning voice of philosophy is not heeded, when it charges natural science with applying its conceptions to materials to which they are inadequate; and its examination of the categories of thought is regarded as an innocent, but also a useless, activity.  For, it is argued, what good can arise from the analysis of our working ideas?  The world looked for causes, and found them, when it was very young; but, up to the time of David Hume, no one had shown what causality meant, and the explanation which he offered is now rejected by modern science, as definitely as it is rejected by philosophy.  Meantime, while philosophy is still engaged in exposing the fallacies of the theory of association as held by Hume, science has gone beyond this category altogether; it is now establishing a theory of the conservation of energy, which supplants the law of causality by tracing it into a deeper law of nature.