‘The world is my representation’: – this holds true for every living, cognitive being, although only a human being can bring it to abstract, reflective consciousness: and if he actually does so he has become philosophically sound. It immediately becomes clear and certain to him that he is not acquainted with either the sun or the earth, but rather only with an eye that sees a sun, with a hand that feels an earth, and that the surrounding world exists only as representation, that is, exclusively in relation to something else, the representing being that he himself is. – If any a priori truth can be asserted, then this is it; for this truth expresses the form of all possible and conceivable experience. This form is more universal than any other form, more universal than time, space and causality, which, in fact, presuppose it. If each of these forms (which we have recognized as so many particular forms of the principle of sufficient reason) applies only to a particular class of representations, then by contrast, subject/object dichotomy is the general form of all these classes. It is the only form under which any representation – whatever kind it may be, abstract or intuitive, pure or empirical – is possible or even conceivable.