Our first conclusion as to the subject-matter of Ethics is, then, that there is a simple, indefinable, unanalysable object of thought by reference to which it must be defined. By what name we call this unique object is a matter of indifference, so long as we clearly recognise what it is and that it does differ from other objects. The words which are commonly taken as the signs of ethical judgments all do refer to it; and they are expressions of ethical judgments solely because they do so refer. But they may refer to it in two different ways, which it is very important to distinguish, if we are to have a complete definition of the range of ethical judgments. Before I proceeded to argue that there was such an indefinable notion involved in ethical notions, I stated (§ 4) that it was necessary for Ethics to enumerate all true universal judgments, asserting that such and such a thing was good, whenever it occurred. But, although all such judgments do refer to that unique notion which I have called good, they do not all refer to it in the same way. They may either assert that this unique property does always attach to the thing in question, or else they may assert only that the thing in question is a cause or necessary condition for the existence of other things to which this unique property does attach. The nature of these two species of universal ethical judgments is extremely different; and a great part of the difficulties, which are met with in ordinary ethical speculation, are due to the failure to distinguish them clearly. Their difference has, indeed, received expression in ordinary language by the contrast between the terms good as means and good in itself, value as a means and intrinsic value. But those terms are apt to be applied correctly only in the more obvious instances; and this seems to be due to the fact that the distinction between the conceptions which they denote has not been made a separate object of investigation. This distinction may be briefly pointed out as follows. (§ 15 ¶ 1)