=70.= And, first of all, there is an ambiguity in the very question: What is good? to which it seems some influence must be attributed. The question may mean either: Which among existing things are good? or else: What _sort of_ things are good, what are the things which, whether they _are_ real or not, ought to be real? And of these two questions it is plain that to answer the first, we must know both the answer to the second and also the answer to the question: What is real? It asks us for a catalogue of all the good things in the Universe; and to answer it we must know both what things there are in the Universe and also which of them are good. Upon this question then our Metaphysics would have a bearing, if it can tell us what is real. It would help us to complete the list of things which are both real and good. But to make such a list is not the business of Ethics. So far as it enquires What is good? its business is finished when it has completed the list of things which ought to exist, whether they do exist or not. And if our Metaphysics is to have any bearing upon this part of the ethical problem, it must be because the fact that something is real gives a reason for thinking that it or something else is good, whether it be real or not. That any such fact can give any such reason is impossible; but it may be suspected that the contrary supposition has been encouraged by the failure to distinguish between the assertion ‘This is good,’ when it means ‘_This sort of thing_ is good,’ or ‘This would be good, if it existed,’ and the assertion ‘This existing thing is good.’ The latter proposition obviously cannot be true, unless the thing exists; and hence the proof of the thing’s existence is a necessary step to its proof. Both propositions, however, in spite of this immense difference between them, are commonly expressed in the same terms. We use the same words, when we assert an ethical proposition about a subject that is actually real, and when we assert it about a subject considered as merely possible.