Eucken maintains that the insufficient attention paid to this priority of the subject is the [p.89] defect of all the systems which have reduced life and all its values to their lowest denominator. A naive realism is a relic of past ancestry; it is a failure to conceive anything as reality unless it lends itself to the senses. Had men not grasped a higher order of reality than that of the external object, none of the mental and moral gains of the world would ever have been realised. Hence, man has to insist that the mental or spiritual life is the possessor of a reality of its own, although much of the material comprising that reality has been drawn from the physical world through the senses. But the spiritual life has proceeded far beyond these initial stages of knowing the world. Material of a kind other than the physical has presented itself to it. Thus, in will-relations we find the material itself belonging to a higher order of existence than the material of the physical world. It is then what might be expected when the spiritual life, within the domain of events of human history, forms a Life-system higher in its nature than the natural process. Eucken then concludes that Nature and History require for their interpretation the presence of a spiritual life. Nature involves the spiritual in the very power of mind in knowing external things. He would not state that the physical course of things is enough in itself to prove the existence of spiritual life. We are uncertain of any working towards [p.90] definite ends in Nature. The whole matter belongs to the region of speculation; and speculation based on something other than observation and experiment has greatly retarded progress in connection with the truest interpretation of the highest things. Eucken would really agree here with the physical scientist pure and simple that, however far back the investigations of the physical world are carried, the scientist does not seem to come to anything at the furthest point which bears more affinity to what is mental than was to be discovered at the point from which he set out.