It is with much diffidence that I send into the world this essay on two of the most important conceptions that occupy the attention of moral philosophers. I am conscious of the great difficulty of most of the main problems of ethics, and of the fact that almost all the assumptions that it seems most natural to make raise problems that for their proper treatment would demand long and careful discussion. I fancy that in some places, in my anxiety to take account of the complications and opposing considerations that demand to be taken account of, I may have made the main outlines of my view difficult to follow; and that in others, in my wish to avoid undue complexity, I may have made general statements without qualifications which will suggest themselves as necessary. I have tried to strike a mean between undue simplicity and undue complexity; but I cannot flatter myself that I have always, or even usually, been successful. Some of the conclusions I have reached seem to me almost certainly true, and others seem to me very doubtful; and I have tried to indicate which I think the more and which the less doubtful.

My main obligation is to Professor H. A. Prichard. I believe I owe the main lines of the view expressed in my first two chapters to his article 'Does Moral Philosophy rest on a Mistake?' (Mind, 1912, 21-37). In addition to this, I have repeatedly discussed many of the main ethical problems with him, and have learnt something from every discussion; I have also had the advantage of reading a good deal that he has written but not published. And finally, he has read in manuscript most of what I have written, and has helped me greatly by exhaustive comments and criticisms. These have been very profitable to me both where (as in the treatment of rightness) he is (I believe) in general agreement with my point of view, and where (as in the treatment of the question what things are good) he to a large extent disagrees.

I wish also to say how much I owe to Professor G. E. Moore's writings. A glance at the index will show how much I have referred to him; and I will add that where I venture to disagree, no less than where I agree, I have always profited immensely from his discussions of ethical problems.

October 1930.

W. D. R.