There is, indeed, no difficulty about the ‘objects’ themselves, in the sense in which I have just used the term. It is easy to say which of them are natural, and which (if any) are not natural. But when we begin to consider the properties of objects, then I fear the problem is more difficult. Which among the properties of natural objects are natural properties and which are not? For I do not deny that good is a property of certain natural objects: certain of them, I think, _are_ good; and yet I have said that ‘good’ itself is not a natural property. Well, my test for these too also concerns their existence in time. Can we imagine ‘good’ as existing _by itself_ in time, and not merely as a property of some natural object? For myself, I cannot so imagine it, whereas with the greater number of properties of objects--those which I call the natural properties--their existence does seem to me to be independent of the existence of those objects. They are, in fact, rather parts of which the object is made up than mere predicates which attach to it. If they were all taken away, no object would be left, not even a bare substance: for they are in themselves substantial and give to the object all the substance that it has. But this is not so with good. If indeed good were a feeling, as some would have us believe, then it would exist in time. But that is why to call it so is to commit the naturalistic fallacy. It will always remain pertinent to ask, whether the feeling itself is good; and if so, then good cannot itself be identical with any feeling. =27.= Those theories of Ethics, then, are ‘naturalistic’ which declare the sole good to consist in some one property of things, which exists in time; and which do so because they suppose that ‘good’ itself can be defined by reference to such a property. And we may now proceed to consider such theories. And, first of all, one of the most famous of ethical maxims is that which recommends a ‘life according to nature.’ That was the principle of the Stoic Ethics; but, since their Ethics has some claim to be called metaphysical, I shall not attempt to deal with it here. But the same phrase reappears in Rousseau; and it is not unfrequently maintained even now that what we ought to do is to live naturally. Now let us examine this contention in its general form. It is obvious, in the first place, that we cannot say that everything natural is good, except perhaps in virtue of some metaphysical theory, such as I shall deal with later. If everything natural is equally good, then certainly Ethics, as it is ordinarily understood, disappears: for nothing is more certain, from an ethical point of view, than that some things are bad and others good; the object of Ethics is, indeed, in chief part, to give you general rules whereby you may avoid the one and secure the other. What, then, does ‘natural’ mean, in this advice to live naturally, since it obviously cannot apply to everything that is natural?