from the scientific side.  It may be that Nature will appear more and more mechanical in many of its manifestations; but even if this should prove to be the case, it can produce no injury whatever to the nature [p.193] and content of spiritual life.  It may be, on the other hand, that the scientific movement now proceeding in the direction of neo-Vitalism will produce results which will modify and even overthrow the mechanical conceptions of life, and thus enable the future to construct a Metaphysic of Nature.[65] The battle between these two schools of science is proceeding to-day.  But even if the final issue should be a decision in favour of mechanism, the destiny of Christianity or of the human soul does not depend upon such a decision.  If the issue should turn in favour of the vitalistic conception, great gains are bound to accrue to religion; for thus a warrant for a belief in a reality higher in nature than what is termed physical will be established and shown to be at work in the origin and constant “becoming” of physical phenomena.  The main point for us to-day is to hold fast to the superiority of spiritual life to all that we know concerning the physical universe.  Unless this is done, we shall lose the deeper inward connections of life, and shall be in danger of sinking back to the level of naturalism—­a level from which the culture and religion of the Western world have partially emerged.  Further, the spiritual nucleus of Christianity [p.194] must be preserved over against the changes of history.  Changes in human society threaten Christianity more directly than even the changes of Nature.  These changes, in so far as they are judged by a spiritual standard to be good, can be accepted by Christianity, but only on the presupposition that Christianity has learned how to differentiate between its Eternal Substance and its temporal form of existence.  The mere flow of the events of Time is insufficient to produce a religion of substance and duration, for here we are dependent upon the content of the moment.  This aspect has been already dealt with in the chapter on Religion and History.[66] A similar necessity for differentiating between the Eternal and the temporary which Eucken enforced in regard to Christianity applies in his view to all the movements of the world.  Whatever form—­scientific, philosophical, social, theological—­these movements may take, they have all to find their meaning in a Standard which is Eternal.  Whenever such a Standard has been recognised, mankind was able to move in an upward direction; whenever it was absent, the complexities of knowledge and life increased and had no light to reflect upon themselves, and no power to [p.195] raise themselves to a higher plane.  When the Eternal and Substantial is present at the governing centre of life, all of reality that can possibly present itself to man is viewed in an entirely different light.  Great spiritual movements cannot possibly arise from any shallower source.  There must be present in