Metaphysical Elements of Ethics

Now in this philosophy (of ethics) it seems contrary to the idea of it that we should go back to metaphysical elements in order to make the notion of duty purified from everything empirical (from every feeling) a motive of action. For what sort of notion can we form of the mighty power and herculean strength which would be sufficient to overcome the vice-breeding inclinations, if Virtue is to borrow her "arms from the armoury of metaphysics," which is a matter of speculation that only few men can handle?

Hence all ethical teaching in lecture rooms, pulpits, and popular books, when it is decked out with fragments of metaphysics, becomes ridiculous. But it is not, therefore, useless, much less ridiculous, to trace in metaphysics the first principles of ethics; for it is only as a philosopher that anyone can reach the first principles of this conception of duty, otherwise we could not look for either certainty or purity in the ethical teaching.

To rely for this reason on a certain feeling which, on account of the effect expected from it, is called moral, may, perhaps, even satisfy the popular teacher, provided he desires as the criterion of a moral duty to consider the problem: "If everyone in every case made your maxim the universal law, how could this law be consistent with itself?" But if it were merely feeling that made it our duty to take this principle as a criterion, then this would not be dictated by reason, but only adopted instinctively and therefore blindly.