I think it will be generally admitted that if Oxford philosophers have any claim to have added in recent years to the store of our philosophical ideas, it lies in their published works on the theory of conduct. I don’t think it can be claimed that, even in this sphere, they have given us many new and illuminating positive truths. After reading Mr. Ross, Professor Prichard, and Mr. Joseph, we are left, I think, with the impression that the whole subject is much more intricate and puzzling than we should have thought possible. I intend in this paper to try and discover what is true in the theories of these three moralists on one of the most difficult and puzzling of ethical problems, viz., “What Renders a Right Act Right?” Professor Prichard and Mr. Ross, in the main, stand together; it is regrettable that Professor Prichard's published work is so very meagre. And if in quoting from his article in Mind, 1912, on “Does Moral Philosophy Rest on a Mistake,” I am doing him an injustice in attributing to him any views which he no longer holds, I am sorry; but modesty in publishing has its penalties, and anyhow, the article is too guilty an offender to get off free, for its annoying subtleties started the whole trouble, and led indirectly to Some Problems in Ethics and the Right and the Good.