Henry Sidgwick is great philosopher. But his masterpiece, The Methods of Ethics, is long and difficult. In this transcribed interview, Mariko Nakano-Okuno tells us who Sidgwick was, what he believed in, and why he’s so significant. She wrote a book entitled Sidgwick and Contemporary Utilitarianism.

Who was Henry Sidgwick?

Henry Sidgwick, a 19th century British moral philosopher, was born in 1838 — a year after Victoria became queen — and died in 1900 — a year before Queen Victoria passed away.

He studied mathematics and classics at Trinity College, Cambridge, and then became interested in John Stuart Mill’s moral philosophy while reading it during his vacation. But he seems to have somewhat vacillated between the study of religious history and the study of moral philosophy when he was in his twenties. He was also not quite convinced by Mill’s proof of utilitarianism, despite its initial appeal, so he decided to scrutinize the relationship of utilitarian ethics to its alternatives. After these early intellectual struggles, in 1874, at age 36, he wrote the first edition of The Methods of Ethics, which he continuously revised through its 7th edition. It is now known as a masterpiece in ethics. Many 20th and 21st century utilitarian philosophers, including G. E. Moore, R. B. Brandt, J. J. C. Smart, R. M. Hare, Derek Parfit, and Peter Singer, refer to Sidgwick when constructing their moral philosophy.  Even opponents of utilitarian ethics, such as John Rawls, often refer to Sidgwick in developing their own arguments.

There are good reasons why Sidgwick’s Methods of Ethics is called a masterpiece in ethics. Sidgwick lived over a century ago, but was decades ahead of his time in presenting analyses and arguments that are still valid in the context of contemporary ethics. His Methods of Ethics contains a brilliant variety of topics that are still discussed today.  For example, you can find act-utilitarian, rule-utilitarian and even two level utilitarian thinking in Book 4, Chapters 4 and 5 of The Methods of Ethics. He anticipates population issues, including Derek Parfit’s repugnant conclusion, in his discussion in Bk. 4 Ch. 1 of the Methods. He extensively analyzes our common notion of justice in Bk. 3, Ch. 5. Discussions of evolutionary theory and its relation to ethics appear in several places in the same volume.

Also remarkable are his meta-ethical analyses of basic moral concepts, such as good, right, pleasure and desire, and of ought-judgments. In fact, if you seek accurate definitions of any key moral concepts, most likely you can find them in his Methods of Ethics. You’ll find a very clear definition of ethics that can hardly be found elsewhere; you can learn about a distinction between volition or will on the one hand, and desire or motives on the other; you’ll see differences between intentions and motives; and you’ll see precise differences between consequentialism and deontology, just to name a few.  

But the greatest contribution Sidgwick made to the field of ethics was his attempt to elucidate the philosophical foundation of the utilitarian principle, or the philosophical foundation of morality in general.

Sidgwick was influential during his life and still has some influence today, but he’s far less widely read than the other fathers of utilitarianism, Bentham and Mill. Why?

In my opinion, Bentham and Mill are to Sidgwick what the Pythagorean theorem is to Euclid’s proof of it. The Pythagorean theorem states that a^2 + b^2 = c^2, or that the squares of the longest side of a right triangle is equal to the sum of the squares of the triangle’s other two sides. This is very simple, and easy to remember; we all know it, and it’s useful. But many of us may just vaguely remember Euclid’s proof of the Pythagorean theorem. Euclid started with a set of simple definitions and several self-evident axioms, and step-by-step, he proved a number of theorems, including the Pythagorean theorem. His proof is clear and logical once it’s stated, but it may be too elaborate to remember.  Many ordinary people can use the Pythagorean theorem without knowing Euclid’s proof.  The Pythagorean theorem is popular, while Euclid’s proof of it is not that popular, but it does not mean that Euclid’s proof of the Pythagorean theorem is unimportant. It’s actually more philosophically profound than the Pythagorean theorem itself.

I see something similar in the relationship between Sidgwick and Bentham or Mill.  Bentham and Mill’s utilitarian principle, and their motto, is very easy to remember: The greatest happiness for the greatest number, or the maximization of the happiness of all parties concerned. Bentham and Mill were great in their lucid formulation of a secular utilitarian principle, and in delineating how to use it in certain kinds of situations. The principle they proposed has been quite useful in dealing with many practical issues.  This is part of the reason why Bentham and Mill are so popular. By contrast, Sidgwick attempted to examine, and hopefully to prove, whether and why we should adopt the utilitarian principle instead of other lines of ethical reasoning. Many ordinary people can use the utilitarian principle without ever questioning its philosophical basis, and that is probably why Bentham and Mill are more popular than Sidgwick. That does not, however, mean that Sidgwick is unimportant.  In fact, his argument is more philosophically profound, and is worth exploring if you are interested in the philosophical foundation of morality, just as Euclid’s proofs and his axiomatic reasoning are worth exploring if you are interested in the philosophical foundation of mathematics.

This mathematical analogy is not my random idea; Sidgwick studied mathematics at Trinity College, and he frequently compares his fundamental moral axioms, and other seemingly self-evident claims, to Euclidian axioms and theorems. He attempted to base utilitarianism on a solid philosophical foundation that consists of a limited number of self-evident axioms, just as Euclid attempted to base geometry on a solid rational foundation that consisted of a limited number of seemingly self-evident axioms. It is clear that Sidgwick’s Methods is a reconstruction of moral philosophy along the same line as Euclid’s systematization of geometry based on his axiomatic reasoning.

You mentioned act utilitarianism and rule utilitarianism. There’s also hedonistic utilitarianism, and there’s preference utilitarianism… what kind of utilitarianism did Sidgwick defend?

Hedonistic utilitarians attempt to maximize people’s happiness, or the surplus of pleasure over pain, while preference utilitarians attempt to maximize people’s preference-satisfactions. Sidgwick clearly defended the hedonistic version of utilitarianism, for he thought the only valuable thing that we can meaningfully seek to attain is the desirable or agreeable feelings in our hearts.

Act utilitarianism is the method of moral thinking in which utilitarian consideration is used to choose a particular course of action: among alternative courses of possible actions, the one that is expected to bring about the maximum happiness of all parties concerned is what one ought to do in that situation. In rule utilitarianism, utilitarian consideration is used to choose a certain general rule that determines what one ought to do. A rule which, when widely and generally accepted, is expected to bring about the best possible happiness of all parties, is the rule you ought to adopt and act according to. There was a controversy during the 1950s and 60s over whether act-utilitarianism or rule-utilitarianism was the proper interpretation of utilitarianism. But I see Sidgwick as a two-level utilitarian who utilizes both act-utilitarian critical thinking and rule-utilitarian morality at two different levels. Some contemporary thinkers regard him solely as an act-utilitarian, but in Book 4 Chapter 4 and 5 of The Methods Sidgwick suggests that utilitarians must respect, and try not to rebel against, the established rules of common-sense morality (p. 475), and that utilitarians should see the rules of our common sense morality as “unconsciously utilitarian” middle axioms, which are useful in making decisions in our daily lives, but which should be modified or revised by referring to utilitarian considerations when the verdict of common sense is obscure and conflicting (p.460). I think Sidgwick is better seen as a two-level utilitarian, as is explained in R.M. Hare’s Moral Thinking.

Let’s go back to the axioms. Mill supported his utilitarianism by appealing to observation. He thought that what is ethical – what is desirable – depended upon what people actually desire. But Sidgwick does not support utilitarianism in this empirical way; rather, he appeals to moral intuitions. What do these moral intuitions amount to?

Sidgwick supported utilitarianism on a different ground than Mill. Sidgwick thought that Mill’s account was contrary to the fact, for ordinary people do not always desire happiness or pleasure. They often desire to achieve non-hedonistic goals, or they act out of their sense of duty or other non-moral motives, without having any felt desires. Even if we assume that people always desire pleasure, it does not follow that they ought to promote it. For Sidgwick, theoretical support for utilitarianism has to come from our fundamental moral intuitions about what we should value as the ultimate good, and how we should pursue the ultimate good on the whole.

According to Sidgwick, the philosophical foundations of ethics consist of at least three self-evident axioms, namely, the Axiom of Justice, the Axiom of Prudence and the Axiom of Rational Benevolence — plus an intuitively plausible claim of Ethical Hedonism. Sidgwick states that these three axioms, and this hedonistic claim, are what any rational individual would accept as self-evident and significant — or at least as highly plausible — after consideration and reflection.

The Axiom of Justice is the philosophical restatement of the Golden Rule, or what is now called the universalizability requirement of moral judgment. It requires consistency in making ought-judgments in the same kinds of situations.  One should not judge an action to be right for A and wrong for B, unless there is some difference between the two individuals, or their circumstances, that provides a reasonable ground for treating them differently.  

The Axiom of Prudence concerns the impartial measurement of the good over time. It requires that, when we look at one’s good on the whole over time, the same amount of goods at two different points in time be weighed equally. So it requires time-indifference in weighing goods, in the assessment of an individual’s lifetime good.

The Axiom of Rational Benevolence requires the impartial measurement of the good of individuals in the assessment of people’s overall good. When one takes an impartial viewpoint that goes beyond one’s self-interest to see a greater whole, or the Point of View of the Universe to use Sidgwick’s metaphor, a rational person will obviously see that the good of one individual has no greater or lesser importance than the good of another individual. So the Axiom of Benevolence requires that, seen from such a broader viewpoint, the same amount of goods of different individuals be weighed equally. It requires personal indifference in weighing people’s goods on the whole.

Ethical Hedonism is the claim that the ultimate good we should seek to attain is happiness, or the surplus of pleasure over pain. As we saw, Sidgwick denied that we always actually desire pleasure, but after a long thought process he carefully reaches the conclusion that happiness, or pleasure, is the only thing we can meaningfully say that this is what we should ultimately seek to attain.

When the axioms of time-indifference and personal indifference are combined with ethical hedonism, we can obtain the claim that the same amount of pleasure ought to have equal weight regardless of who feels it and when it is felt. This last claim amounts to Bentham’s dictum, “everybody to count for one, nobody for more than one,” which provides the theoretical basis for the utilitarian principle. This is how Sidgwick attains utilitarian ethics by appealing to what he claims are our self-evident moral intuitions, briefly speaking.  

Questions may arise as to how to interpret these fundamental axioms; whether, and in what sense, they are truly self-evident; whether these axioms state objective normative truths or our subjective commitments, etc.  There is room for criticizing Sidgwick’s moral philosophy in this regard, but I believe these are questions not only about Sidgwick’s ethics, but also about utilitarian ethics and moral philosophy in general.

When I read Sidgwick, I was struck by how masochistically he makes objections to himself. What are some of Sidgwick’s main self-criticisms?

His most serious self-criticism was probably his concession of the unresolvable conflict between rational self-love and rational benevolence, which he called “the Dualism of Practical Reason.” As I said, the combination of the Axioms of Prudence, Benevolence and Ethical Hedonism yields the utilitarian principle, which he sees as a rational principle of conduct.  However, if we combine ethical hedonism with the Axiom of Prudence alone, that would yield rational egoism, which claims that one should aim to maximize one’s self-interest over time. The Axiom of Prudence is considered a rational principle, and ethical hedonism is also considered a reasonable answer to the question of what constitutes one’s good, so the combination of these two claims must bring about the conclusion that it is rational to pursue one’s self-interest over time. Thus, Sidgwick claimed that, as a matter of theory, egoism can be as firmly endorsed as utilitarianism. The phrase “dualism of practical reason” means that both egoism and utilitarianism seem to have an equally firm rational basis. Neither of them looks irrational. Still, egoism and utilitarianism often require us to do two different, mutually incompatible, things.
Some contemporary theorists have attempted to resolve this problem. For example, Katarzyna de Lazari-Radek and Peter Singer have recently developed an intriguing re-interpretation of Sidgwick’s axioms in their Point of View of the Universe (Oxford U. P., 2014), claiming that the Axiom of Benevolence should always be adopted as rational and authoritative, and that therefore the utilitarian reasoning, which is based on the Axiom of Benevolence, is considered “more rational” than pursuit of one’s self-interest, which lacks the Axiom of Benevolence. Their approach is worth exploring because, even today, the conflict between self-interest and benevolence is one of the profoundest problems in theoretical and practical ethics. Nonetheless, I think Sidgwick was honest, and right, in confessing that this conflict between rational egoism and rational benevolence would remain unresolved. In fact, the Axiom of Benevolence has no persuasive power for those who are not interested in becoming rational at all, or for those who refuse to take the viewpoint of the universe. As I understand it, Sidgwick was bitterly accurate in recognizing that his Axiom of Benevolence is only valid for those who are already committed to rationality and to taking a broader, disinterested viewpoint. So, although some may regard the dualism of practical reason as demonstrating Sidgwick’s failure to fully rationalize ethics, I would rather regard it as representing his uncompromising precision.

Another potential weakness of Sidgwick’s ethics is his proof of hedonism, which may not be convincing enough to turn all of us into hedonistic utilitarians. In order to “prove” that the sole, ultimate good we should seek is pleasure, or “desirable feelings,” Sidgwick proceeds by asking what we, upon reflection, would regard as ultimately desirable. During this process, a person with an egoistic tendency may naturally regard his or her own pleasure as the only thing that is ultimately desirable, whereas a more altruistic person would regard all the positive internal feelings of all sentient beings as the ultimate good; some of us may, perhaps, end up somewhere between the two, believing, for example, that we should care about our loved ones’ happiness or our community’s happiness first and foremost. Still others may possibly regard other things, such as aesthetic ideals and virtues, as the ultimate goal of actions. If this is the case, Sidgwick’s argument may not lead us to a typical utilitarian claim, which is that we should consider any conscious beings’ pleasurable feelings to be the ultimate good we should seek to maximize. There could be different, yet reasonable, perspectives on our pleasures and pains, on life and death.