All the ethical truth which can possibly be conveyed by such an assertion would be just as well conveyed by saying that the ideal consisted in the realisation of a particular kind of self, which might be either real or purely imaginary. ‘Metaphysical Ethics,’ then, involve the supposition that Ethics can be _based_ on Metaphysics; and our first concern with them is to make clear that this supposition must be false. [21] Prof. J. S. Mackenzie, _A Manual of Ethics_, 4th ed., p. 431. The italics are mine. =68.= In what way can the nature of supersensible reality possibly have a bearing upon Ethics? I have distinguished two kinds of ethical questions, which are far too commonly confused with one another. Ethics, as commonly understood, has to answer both the question ‘What ought to be?’ and the question ‘What ought we to do?’ The second of these questions can only be answered by considering what effects our actions will have. A complete answer to it would give us that department of Ethics which may be called the doctrine of _means_ or practical Ethics. And upon this department of ethical enquiry it is plain that the nature of a supersensible reality may have a bearing. If, for instance, Metaphysics could tell us not only that we are immortal, but also, in any degree, what effects our actions in this life will have upon our condition in a future one, such information would have an undoubted bearing upon the question what we ought to do. The Christian doctrines of heaven and hell are in this way highly relevant to practical Ethics. But it is worthy of notice that the most characteristic doctrines of Metaphysics are such as either have no such bearing upon practical Ethics or have a purely negative bearing--involving the conclusion that there is nothing which we ought to do at all. They profess to tell us the nature not of a future reality, but of one that is eternal and which therefore no actions of ours can have power to alter. Such information _may_ indeed have relevance to practical Ethics, but it must be of a purely negative kind. For, if it holds, not only that such an eternal reality exists, but also, as is commonly the case, that nothing else is real--that nothing either has been, is now, or will be real in time--then truly it will follow that nothing we can do will ever bring any good to pass. For it is certain that our actions can only affect the future; and if nothing can be real in the future, we can certainly not hope ever to make any good thing real. It would follow, then, that there can be nothing which we ought to do. We cannot possibly do any good; for neither our efforts, nor any result which they may seem to effect, have any real existence. But this consequence, though it follows strictly from many metaphysical doctrines, is rarely drawn. Although a metaphysician may say that nothing is real but that which is eternal, he will generally allow that there is some reality also in