The arrangement of transcendental philosophy itself is determined by those original convictions, whose validity it asserts. Those convictions must, in the first place, be sought in the common understanding. If, therefore, we fall back upon the standpoint of the ordinary view, we find the following convictions deeply engraven in the human understanding: A. That there not only exists outside of us a world of things independent of us, but also that our representations agree with them in such a manner that there is nothing else in the things beyond what they present to us. The necessity which prevails in our objective representations is explained by saying that the things are unalterably determined, and that, by this determination of the things, our ideas are also indirectly determined. By this first and most original conviction, the first problem of the philosophy is determined, _viz._: to explain how representations can absolutely agree with objects existing altogether independently of them. Since it is upon the assumption that things are exactly as we represent them—that we certainly, therefore, know things as they are in themselves—that the possibility of all experience rests, (for what would experience be, and where would physics, for example, wander to, but for the supposition of the absolute identity of being and seeming?) the solution of this problem is identical with theoretical philosophy, which has to examine the possibility of experience. B. The second equally original conviction is, that ideas which spring up in us freely and without necessity are capable of passing from the world of thought into the real world, and of arriving at objective reality. This conviction stands in opposition to the first. According to the first, it is assumed that objects are unalterably determined, and our ideas by them; according to the other, that objects are alterable, and that, too, by the causality of ideas in us. According to the first, there takes place a transition from the real world into the world of ideas, or a determining of ideas by something objective; according to the second, a transition from the world of ideas into the real world, or a determining of the objective by a (freely produced) idea in us. By this second conviction, a second problem is determined, _viz._: how, by something merely thought, an objective is alterable, so as completely to correspond with that something thought. Since upon this assumption the possibility of all free action rests, the solution of this problem is practical philosophy.