And it has an important bearing on the distinction between those moral rules which deal with actions and those which deal with feelings, for the following reason. The philosopher Kant laid down a well-known proposition to the effect that "ought" implies "can": that is to say, that it cannot be true that you "ought" to do a thing, unless it is true that you _could_ do it, _if_ you chose. And as regards one of the senses in which we commonly use the words "ought" and "duty," I think this rule is plainly true. When we say absolutely of ourselves or others, "I ought to do so and so" or "you ought to," we imply, I think, very often that the thing in question is a thing which we _could_ do, _if_ we chose; though of course it may often be a thing which it is very difficult to choose to do. Thus it is clear that I cannot truly say of anyone that he ought to do a certain thing, if it is a thing which it is physically impossible for him to do, however desirable it may be that the thing should be done. And in this sense it is clear that it cannot be truly said of me that I ought not to have a certain feeling, or that I ought not to have had it, if it is a feeling which I could not, by any effort of my will, prevent myself from having. The having or the prevention of a certain feeling is not, of course, strictly ever a _physical_ impossibility, but it is very often impossible, in exactly the same sense, in which actions are physically impossible--that is to say that I could not possibly get it or prevent it, even if I would. But this being so, it is plain that such a moral rule as that I ought not to covet my neighbour's possessions is, if it means to assert that I ought not, in that sense in which "ought" implies "can," a rule which cannot possibly be true. What it appears to assert is, absolutely universally, of _every_ feeling of covetousness, that the feeling in question is one which the person who felt it _ought_ not to have felt. But in fact a very large proportion of such feelings (I am inclined to say the vast majority) are feelings which the person who felt them could not have prevented feeling, if he would: they were beyond the control of his will. And hence it is quite emphatically _not_ true that none of these feelings _ought_ to have been felt, if we are using "ought" in the sense which implies that the person who felt them _could_ have avoided them. So far from its being true that absolutely _none_ of them ought to have been felt, this is only true of those among them, probably a small minority, which the person who felt them _could_ have avoided feeling. If, therefore, moral rules with regard to feelings are to have a chance of being _nearly_ true, we must understand the "ought" which occurs in them in some other sense. But with moral rules that refer to actions the case is very different. Take stealing for example. Here again what the Eighth Commandment appears to imply is that absolutely every theft which has