The answer, from Kant's own lips, is this: "There is nothing in the world, nor, generally speaking, even out of it, possible to be conceived, which can without limitation be held good, but a _Good Will_." The good is not in the end attained, not even in the volition, but is a principle resident in the will itself. "The volition is between its principle _a priori_, which is formal, and its spring _a posteriori_, which is material; and since it must be determined by something, and being deprived of every material principle, it must be determined by the formal." Now, although President Hopkins considers Moral Philosophy as a philosophy of _ends_, he evidently does not mean ends _a posteriori_ and _material_, but ends _a priori_, using the term as the best objective translation of _principles_. Almost as if with the conscious design of making his work harmonize with the groundwork furnished by Kant, he has developed a graduated series of conditions, according to which we ascend "the great world's altar-stairs," from lower and conditioned good up to that good which is the condition of all, itself unlimited, namely, in the will fulfilling its original design. The "law of limitation," according to which not only the subordinate powers of man, but even the forces of Nature, from those concerned in the highest animal organization down to that of gravitation, are made to take their places in the chain of dependence which hangs from the human will, is the most important part, scientifically, of the whole work. It is in accordance with this law that the science of Morals becomes a structure,--universal in its base and regularly ascending after the order of Nature, harmonious in all its parts, and proceeding upward within hearing of universal harmonies. Hitherto there has been no such structure; but only tabernacles have been built, because there was no Solomon to build a temple. Once having determined the connection which there is between the Will and the principle of Good, there still remains to be determined the place which Reason has in this connection.