C. D. Broad, Five Types of Ethical Theory, 1930
(E) CLASSIFICATION OF THE METHODS OF ETHICS. As we have seen in the Synopsis, Sidgwick reduces the fundamental types of ethical theory to three, viz., Intuitionism, Egoistic Hedonism and Utilitarianism. The only criticism that I wish to make at this point is that his division does not seem to rest on any very clear principle. The name "Intuitionism" seems to suggest an epistemic principle of classification, and the opposite of it would seem to be "Empiricism". On the other hand, the opposition of Egoistic and Universalistic Hedonism to Intuitionism rests on a quite different basis, viz., on whether some types of action are intrinsically right or wrong or whether the rightness or wrongness of actions always depends on their conduciveness to certain ends. This of course is not an epistemic question at all. And this cross-division leads to needless complications in Sidgwick's exposition. He has to recognise that, from an epistemic point of view, all three types of theory involve ethical intuitions. For the two types of Hedonism involve at least the intuition that pleasure, and nothing else, is intrinsically desirable. He thus has to distinguish between a wider and a narrower sense of "Intuitionism". All this seems rather untidy and unsatisfactory. I would therefore propose the following amendments. I would first divide ethical theories into two classes, which I will call respectively deontological and teleological.
Deontological theories hold that there are ethical propositions of the form: "Such and such a kind of action would always be right (or wrong) in such and such circumstances, no matter what its consequences might be." This division corresponds with Sidgwick's Intuitionism in the narrower sense. Teleological theories hold that the rightness or wrongness of an action is always determined by its  tendency to produce certain consequences which are intrinsically good or bad. Hedonism is a form of teleological theory. It is plain that teleological theories can be subdivided into monistic and pluralistic varieties. A monistic theory would hold that there is one and only one characteristic which makes a state of affairs good or bad intrinsically. A pluralistic theory would hold that there are several independent characteristics of this kind. Hedonism is a monistic teleological theory. I think that a similar subdivision could be made among deontological theories. It might be held that all the various moral rules recognised by a deontological theory are determinate forms of a single rule, or at any rate that they all answer to a single necessary and sufficient criterion. This seems to have been Kant's view. Such a theory is monistic. A deontological theory which held that there is a number of independent moral rules would be pluralistic.
Both kinds of teleological theory can now be divided on a new principle. The end to be aimed at is of course never a characteristic in the abstract; it is always a concrete state of affairs in which a certain characteristic, or characteristics, is manifested. And the question arises whether it is the agent's duty to aim at the manifestation of this desirable characteristic in himself only or in a larger circle. We thus get a subdivision into egoistic and non-egoistic types of teleological theory. Utilitarianism, e.g., may be described as a non-egoistic form of monistic teleological theory.
The principles of division which I have suggested are clear in outline, and they have the advantage of not introducing epistemological considerations. We must remember, however, that purely deontological and purely teleological theories are rather ideal limits than real existents. Most  actual theories are mixed, some being predominantly deontological and others predominantly teleological. Sidgwick, e.g., is definitely a Hedonist, and so far a monistic teleologist, though he cannot make up his mind as between the egoistic and the non-egoistic forms of hedonism. But this is not the whole truth about his position. He also accepts as self-evident certain abstract principles about the right way of distributing a given amount of happiness. These modes of distribution ought to be followed, on his view, because they are intrinsically right, and not merely because they are likely to increase the amount of happiness to be distributed in future. To this extent Sidgwick's theory must be counted as deontological. When, as with Sidgwick, the only deontological principles which the moralist accepts are about the right distribution of something which is held to be intrinsically desirable, his system must be regarded as almost purely › teleological.
DETAILED DISCUSSION OF EACH OF THE THREE METHODS.