Kant’s error, an error of very wide bearing which has not even yet been overcome, was first of all in bringing the outer and inner Man into relation with the ideas of space and time by pure scheme, though the meanings of these are numerous and, above all, not unalterable; and secondly in allying arithmetic with the one and geometry with the other in an utterly mistaken way. It is not between arithmetic and geometry—we must here anticipate a little—but between chronological and mathematical number that there is fundamental opposition. Arithmetic and geometry are _both_ spatial mathematics and in their higher regions they are no longer separable. _Time-reckoning_, of which the plain man is capable of a perfectly clear understanding through his senses, answers the question “When,” not “What” or “How Many.” Footnote 2: One cannot but be sensible how little depth and power of abstraction has been associated with the treatment of, say, the Renaissance or the Great Migrations, as compared with what is obviously required for the theory of functions and theoretical optics. Judged by the standards of the physicist and the mathematician, the historian becomes _careless_ as soon as he has assembled and ordered his material and passes on to interpretation. ----- IV Nature is the shape in which the man of higher Cultures synthesizes and interprets the immediate impressions of his senses. History is that from which his imagination seeks comprehension of the living existence of the world in relation to his own life, which he thereby invests with a deeper reality. Whether he is capable of creating these shapes, which of them it is that dominates his waking consciousness, is a primordial problem of all human existence.