Lectures on Moral Science.  Delivered before the Lowell Institute, Boston.  By MARK HOPKINS, D.D., LL.D.  Boston:  Gould and Lincoln. 12mo.

It is a little curious that there is not a single science in which man is constitutionally, and therefore directly interested, to which Emanuel Kant has not, in one way or another, written a Prolegomena.  Professionally he did so in the case of Metaphysic:  and out of the great original claim which he here established there emanates a separate claim, in each particular science of the order already indicated, to a sublime dictatorship.  And chiefly is this claim valid in Moral Philosophy; for it was his province, the first of all men, clearly to reveal, as a scientific fact certified by demonstration, the divine eminence of the practical above the merely speculative powers of man,—­the fulfilment of which mission justly entitled him to all the privileges incident to the vantage-ground thus gained,—­privileges widely significant in a survey of that field where chiefly these practical powers hold their Olympian supremacy, the field of Moral Philosophy.

Nothing could have afforded us a better excuse for a resume of Kant, in this connection, than the new work of Dr. Hopkins.  Of the many treatises on Moral Science with which the reading world has been flooded and bewildered since the time of Coleridge, there is this one alone found worthy of being ranged along-side of the works of the old Koenigsberg seer,—­the one alone which, like his, deals with the grander features of the science.  It is the best realization objectively of Kant’s subjective principles that has yet been given.  But how, the plain English reader will ask, are we to understand from this the place which the new work takes in literature?  Not readily, indeed, unless one has already taken the trouble to examine such of Kant’s treatises as have found their way out of German into hardly tolerable English, and has, moreover, reflected upon the importance of the principles therein established.  But, of those who will read this notice, not one out of fifty has had even the opportunity for examination, not one out of five thousand has really taken the opportunity, and, of those that have, one half, at least, have done so independently of any philosophic aim, and have therefore reflected to very little purpose on the principles involved.  Therefore, what the reader could not or has not chosen to do for himself we will do for him, at the same time congratulating him that there is now placed in his hands as complete and perfect a structure outwardly, in the work under notice, as the groundwork furnished by the old master was, in its subjective analysis, simple and profound.

Those who approach human nature, or the nature outside of us, with a reverence for reality, will give precedence, after the manner of Nature, to those powers which are predominant and determinative; and in man these are Reason and Will.  These two exist as identical in Personality, which we may denominate as we choose, whether Rational Will, or, as Kant does more frequently, Practical Reason.  Here, in the identity of these two powers in Personality, and still more in their relation to each other as they are differentiated in personal existence, does Morality originate and develop according to principles.