The proposed question, how is a being for us possible? abstracts itself from all being; i. e. it must not be understood, as if the question posited a not-being; for in that case the conception of being would only be negated, but not abstracted from. On the contrary, the question does not entertain the conception of being at all, either positively or negatively. The proposed question asks for the ground of the predicate of being, whether it be applied positively or negatively; but all ground lies beyond the grounded, i. e. is opposed to it. The answer must, therefore, if it is to be an answer to this question, also abstract from all being. To maintain, _a priori_, in advance of an attempt, that such an abstraction is impossible in the answer, because it is impossible in itself, would be to maintain likewise, that such an abstraction is impossible in the question; and hence, that the question itself is not possible, and that the problem of a science of metaphysics, as the science which is to solve the problem of the ground of being for us, is not a problem for human reason. That such an abstraction, and hence such a question, is contrary to reason, cannot be proven by objective grounds to those who maintain its possibility; for the latter assert that the possibility and necessity of the question is grounded upon the highest law of reason—that of self-determination, (Practical legislation,) under which all other laws of reason are subsumed, and from which they are all derived, but at the same time determined and limited to the sphere of their validity. They acknowledge the arguments of their opponents willingly enough, but deny their application to the present case; with what justice, their opponents can determine only by placing themselves upon the basis of this highest law, but hence, also, upon the basis of an answer to the disputed question, by which act they would cease to be opponents. Their opposition, indeed, can only arise from a subjective defect—from the consciousness that they never raised this question, and never felt the need of an answer to it. Against this their position, no objective grounds can, on the other hand, be made valid, by those who insist on an answer to the question; for the doubt, which raises that question, is grounded upon previous acts of freedom, which no demonstration can compel from any one. III. Let us now ask: Who is it that undertakes the demanded abstraction from all being? or, in which of the two series does it occur? Evidently, in the series of philosophical argumentation, for another series does not exist.