Many of my philosophical colleagues around the world will look down their noses at me for saying this, but I enjoy teaching. I always have. This past semester, I taught two sections of Ethics, one with 34 students and the other with 35. It was so enjoyable that there were days when I couldn’t wait to get into the classroom. On the morning of the day in which I was scheduled to lecture on W. D. Ross’s moral theory, I woke up at 4:00, more than two hours before rising time. I was so excited about lecturing on Ross that I couldn’t get back to sleep! You probably think I’m kidding. I’m dead serious.

One reason I enjoyed my Ethics courses so much is that I used a different book. For many years, I used James Rachels’s book The Elements of Moral Philosophy (5th ed., 2007). The book—which I’ve heard is the best-selling ethics textbook in the world—is accessible to students and covers most of what I want to cover, but Rachels is spectacularly unfair to ethical egoism, divine-command theory, and natural-law theory. I finally tired of apologizing to the students for his unsympathetic and shallow discussions. This semester, I went back to a book that I used for the first time 20 years ago, when I was a graduate student: Fred Feldman’s Introductory Ethics (1978). The book is still in print—in its original edition. You might wonder how this can be, but not much changes in ethical theory. There is still a great divide between consequentialism and deontology; there are still absolute and moderate deontologists; there are still utilitarians (albeit of different stripes); and, most importantly, the methods of argumentation, analysis, and criticism that I inculcate in my students haven’t changed in the past three decades. In short, the book is as timely as ever.

When I first used Feldman, in the spring of 1987, I didn’t have a solid grounding in the history of ethics—or even in the contemporary work being done in ethics. As a result, I stayed pretty close to the text in my lectures. But now I have a much firmer grounding. I use the text as a point of departure rather than as the focal point. Students who didn’t come to class on a regular basis (attendance was not part of their grade) probably thought they could do well on the examinations merely by reading the text. Ha! They were in for a rude awakening, for the lectures were at least as important as the text this time around. I intend to continue using Feldman. I know it’s impossible, but the text seemed to get better with the passage of time. What got better, obviously, was my own understanding of the material.

I covered 10 of the book’s 15 chapters (not counting the short concluding chapter). I had hoped to get to the chapters on metaethics, but we didn’t. That was fine. It’s enough to have covered the chapters on normative ethical theory. Let me explain what this is, for those of you who don’t know. A normative ethical theory provides a criterion of rightness. Rightness is a property of actions. A criterion, in general, is a statement of necessary and sufficient conditions for something’s being the case. To put it in ordinary language, a normative ethical theory tells us what it is that makes right acts right and wrong acts wrong. It’s a sorting device. I’m sure you’ve wondered about this. You make moral judgments every day. You say, for example, that it was wrong for so and so to do X, that it would be wrong if you did Y, and so forth. What is it that makes these acts wrong? To answer that question is to begin to theorize.

I covered six normative ethical theories this semester. Here they are:

1. Act utilitarianism. An act is right if and only if it maximizes overall utility. There are different ways to understand “utility.” Some utilitarians understand it as happiness, some as pleasure, some as welfare, and some as the satisfaction of preferences. In calculating utility, everyone affected by the action counts, and counts equally. Even animals count.

2. Rule utilitarianism. An act is right if and only if it is permitted by a rule that maximizes overall utility. This is still a form of utilitarianism, but instead of evaluating actions directly, one is to evaluate rules first (such as “When you have made a promise, keep it”) and then act in accordance with utility-maximizing rules. Rule utilitarianism is sometimes called “indirect” or “restricted” utilitarianism. There is a debate about whether John Stuart Mill (1806-1873) was an act utilitarian or a rule utilitarian. A plausible case can be made for each view.

3. Egoism. An act is right if and only if it maximizes agent utility. This is like act utilitarianism except that only one person’s utility matters: the agent’s. You are to do what’s best for you; I’m to do what’s best for me; and so on for every other agent. This theory does not tell you to do whatever feels good. It is, in fact, an austere theory. It requires that you maximize your long-term rational self-interest. It is no more permissible for you to “short” your future selves than it is for act utilitarians to “short” strangers. Everyone counts, and counts equally. In the case of egoism, this means that every one of your selves, at all life stages, counts, and counts equally.

4. Kantianism. An act is right if and only if it is universalizable (or universally prescribable). If you can’t consistently will that everyone in your circumstances do what you’re proposing to do, then it’s wrong for you to do it. Another way to put this is that you must never treat persons as mere means to your ends. In effect, this means not forcing anyone to do anything, not coercing anyone, and not manipulating anyone. All interactions must be consensual. Since animals lack the capacity to consent, they have no moral status, according to Kant. They are perpetual children.

5. Rawls’s social-contract theory. An act is right if and only if it is permitted by the moral code that would be agreed to by individuals who are deprived of information about their morally irrelevant features, such as race, sex, intelligence, and age. Actually, there are two versions of contractarianism. In one of them, which goes back to Thomas Hobbes (1588-1679), individuals know what their characteristics are. In the other, they are deprived of this knowledge. The idea of the second version is to force individuals to be fair. If I don’t know whether I’m male or female, I can hardly be biased against one or the other.

6. Ross’s formalism. An act is right if and only if it is a prima facie duty and there is no alternative act that is a more stringent prima facie duty. Ross claimed that there are seven prima facie (“presumptive”) duties: fidelity, reparation, gratitude, justice, beneficence, self-improvement, and nonmaleficence. A given act can fall under more than duty. For example, if I make a promise to murder someone (stupid me!), I have a prima facie duty to keep it, since keeping it would be a case of fidelity, but I also have a prima facie duty not to keep it, since doing so would mean harming someone (which is prohibited by the prima facie duty of nonmaleficence). Ross insisted that prima facie duties are irreducible (to utility, for example). All one can do, on any occasion, is bring all relevant duties to bear and, in cases of conflict, resolve the conflict by determining which duty is more stringent. Ross is a moderate deontologist. Kant is an absolute deontologist.

These are just thumbnail sketches, obviously. I could write a whole book about each theory. At the end of the course, I asked my students which theory best systematizes their moral judgments. I was surprised by the result:

Act utilitarianism: 15.
Rule utilitarianism: 6.
Egoism: 5.
Kantianism: 13.
Rawls’s social-contract theory: 12.
Ross’s formalism: 18.

Ross claimed that his prima facie duties are part of “our ordinary moral consciousness.” This may explain why his theory resonated with my students. Then again, maybe they chose it because, having been discussed last, it was still fresh in their minds. Which theory are you attracted to, if any?

Addendum: One shortcoming of Feldman’s book (no book is perfect) is that it doesn’t cover either the divine-command theory of morality or natural-law theory, perhaps because these theories presuppose the existence of God. Curiously, there is no mention of God in the book. This would have made it incomprehensible to most moral philosophers until very recently. In future courses, I will lecture on these theories as well as the others.