[This book is now reprinted without any alteration whatever, except that a few misprints and grammatical mistakes have been corrected. It is reprinted, because I am still in agreement with its main tendency and conclusions; and it is reprinted without alteration, because I found that, if I were to begin correcting what in it seemed to me to need correction, I could not stop short of rewriting the whole book. G. E. M.] CAMBRIDGE, 1922. TABLE OF CONTENTS. CHAPTER I. THE SUBJECT-MATTER OF ETHICS. A. SECTION. PAGE =1.= In order to define Ethics, we must discover what is both common and peculiar to all undoubted ethical judgments; 1 =2.= but this is not that they are concerned with human conduct, but that they are concerned with a certain predicate ‘good,’ and its converse ‘bad,’ which may be applied both to conduct and to other things. 1 =3.= The subjects of the judgments of a scientific Ethics are not, like those of some studies, ‘particular things’; 3 =4.= but it includes all _universal_ judgments which assert the relation of ‘goodness’ to any subject, and hence includes Casuistry. 3 B. =5.= It must, however, enquire not only what things are universally related to goodness, but also, what this predicate, to which they are related, is: 5 =6.= and the answer to this question is that it is indefinable 6 =7.= or simple: for if by definition be meant the analysis of an object of thought, only complex objects can be defined; 7 =8.= and of the three senses in which ‘definition’ can be used, this is the most important. 8 =9.= What is thus indefinable is not ‘the good,’ or the whole of that which always possesses the predicate ‘good,’ but this predicate itself. 8 =10.= ‘Good,’ then, denotes one unique simple object of thought among innumerable others; but this object has very commonly been identified with some other--a fallacy which may be called ‘the naturalistic fallacy’ 9 =11.= and which reduces what is used as a fundamental principle of Ethics either to a tautology or to a statement about the meaning of a word. 10 =12.= The nature of this fallacy is easily recognised; 12 =13.= and if it were avoided, it would be plain that the only alternatives to the admission that ‘good’ is indefinable, are either that it is complex or that there is no notion at all peculiar to Ethics--alternatives which can only be refuted by an appeal to inspection, but which can be so refuted. 15