2. Moral Theories

Introduction

Moral theories are general theories that try to answer the questions ‘what is morally good?’ and ‘how can we distinguish good from bad?’ In applied ethics , we often use principles that we can trace back to these theories. Therefore, it is vital that we know moral theories and what the weak points of these moral theories are. In the following chapter, we discuss four approaches: utilitarianism , deontology , virtue ethics , and care ethics . But before we start, a warning is in order. When confronted with certain ethical questions from a specific field of study, such as biomedicine, we usually do not pick out our favourite theory and apply it. Although some ethicists consider themselves as strictly ‘utilitarian’ or ‘deontologian’—this view is called ethical absolutism or monism—ethical questions are often too complex and too diverse to be solved with one theory. For example, ethical questions can pertain to policymaking, interpersonal relations, or both. Moreover, we can ask ourselves whether there is always one good answer to an ethical dilemma. This does not mean that there cannot be better and worse answers in any case. At the same time, knowing the different aspects of morality through these moral theories, and the challenges that each approach has, helps you look at a specific ethical question through different angles.

Courses on applied ethics , such as bioethics, often start with an overview of moral theories and principles, as does this book. This ubiquity of moral theories might give the impression that they represent opinions about which underlying framework of morality is the best. Indeed, that may be the way they were conceived in the first place. It is more helpful, however, to view them as describing aspects of morality. As such, they are valuable tools: you should try to look at ethical dilemmas using different approaches and theories and know the drawbacks to each approach. Moreover, it is essential to realize that a specific type of reasoning may be utilitarian or deontological, but that does not mean that applying utilitarianism or deontology to a specific ethical dilemma yields straightforward answers. We will see some examples later in this chapter.

Utilitarianism

Imagine that you are standing beside tracks, looking at a trolley approaching. You notice that there are five people tied on the tracks. If the trolley continues its course, it will kill these five people. However, you can ensure that the trolley will get onto another track by pulling a particular lever. There is one person tied to this alternative track. This person will be killed if you pull the lever. What should you do? This thought experiment was initially described in 1967 by British philosopher Philippa Foot (1920–2010). It seems reasonable to answer here that it is better to cause the death of one person than the death of five persons. If you want to find out what the best course of action is, looking at the consequences looks like a good place to start. However, it may be that pulling the lever does not sit well with some of us. Aren’t we actively killing that one person, and is killing not a bad thing no matter what? What if that one person is very young and the five other ones are very old? Or if that one is a loved one, such as a friend or child?

A moral theory that evaluates actions based on the consequences of these actions is consequentialism. The best-known version of consequentialism is utilitarianism. Utilitarianism states that an act is good if it results in ‘the greatest good for the greatest number of people’. Hence, it is a question of cost-benefit analysis: you weigh up what it would cost to do something and the consequences. This idea, although very old, was first systematized in 1789 by Jeremy Bentham (1748–1832). In the spirit of Enlightenment , Bentham states that faith is secondary to reason: moral rules should not come from God, but you should deduce them by thinking properly. He proposed a hedonistic calculus to find out what the good consequences are. Only pleasure matters: what is good is what causes us pleasure, and what is immoral is what causes us pain. Pleasure (or pain) can be measured in intensity, length, certainty, and whether they are followed by opposite emotions.

However, many philosophers question the use of pleasure as a basis for cost-benefit analysis. Robert Nozick (1938–2002) was one of them. In Anarchy, State and Utopia (2013), he describes a thought experiment called the experience machine: imagine that there is a machine that gives you pleasurable experiences. According to the hedonistic approach, the mere experience of pleasure should be equivalent to the proper acts that give you pleasure. Intuitively, however, Nozick states that people would prefer to actually do the acts that give pleasure rather than merely experience the pleasure in itself. Hence, hedonism is based on a wrong assumption.

John Stuart Mill (1806–1873) describes the utility principle as follows: “Actions are right in proportion as they tend to promote happiness, wrong as they tend to produce the reverse of happiness, i.e. pleasure or absence of pain” (Mill, 2001, p. 7). He considered some actions to be qualitatively better than others. For example, pleasures of the mind (intellectual activity) are more important than physical activity (sport). In the twentieth century, people tried to solve problems with the hedonistic interpretation of the utility principle by stating that good has to be defined based on the satisfaction of preferences rather than the provision of pleasure (preference utilitarianism). Preferences are not always purely hedonistic—some prefer, for instance, to spend time caring for people in need over going out and enjoying life.

Another further elaboration of utilitarianism was factoring rules into the calculus. Act utilitarianism demands that each act should be treated separately. Rule utilitarianism demands that an act be judged based on more general rules to maximize happiness. It may be, for example, acceptable to lie to your partner when you have cheated on them because the truth would hurt them and cause them pain. However, rule utilitarianism suggests that breaking the rule ‘do not lie’ would undermine the maximization of happiness in the long run. It may ultimately lead to a breach of confidence. Lying should not be tolerated because it undermines the foundations of society and leads to less well-being.

Utilitarianism has good points. When it started gaining popularity, it was ethically progressive for its time because it counts everyone who can experience happiness as relevant for moral consideration, including women and children. Jeremy Bentham referred explicitly to animals when he stated: “The question is not, ‘Can they reason?’ nor, ‘Can they talk?’ but ‘Can they suffer?’”(Bentham, 1789, p. 311). Peter Singer (born 1946), a contemporary utilitarian philosopher, uses similar arguments to defend non-human animals. According to him, to make a moral distinction between humans and non-human animals is speciesism. Speciesism is analogous to racism and sexism. It means that people attribute different values to different creatures on the basis of their similarity to their own species—in this case, to the human species, which is thus deemed superior.

Utilitarianism appeals to our common sense and is a sound basis for policymaking. When policymakers are confronted with the fact that they have little money available for research, should this money not be spent on diseases that cause the most suffering? Should it not be spent on cancer research rather than Botox treatments for cosmetic purposes? Here, we encounter the weak points of utilitarianism . How can we measure suffering, and who is then suffering the most? How much weight should we give to the suffering of animals ? What about foetuses or the biosphere?

Because utilitarianism is about deciding what is right or wrong based on future results, it remains, to some extent, speculative. We could defend nuclear energy because it produces far less CO² than fossil fuels and could, hence, be part of the solution to climate change . The risk of a nuclear disaster might annihilate this benefit. Utilitarianist thinking can also cause suffering and can, specifically, be detrimental for minorities. Indeed, when an action benefits 51% of the population—meaning that their happiness increases—at the cost of a decrease in the happiness of 49% of the population, is this a morally just act? Let us say you are a doctor with five patients, each needing a different organ to survive. You find a lonely and homeless man who is the perfect match to save all five lives. Should you kill this man?

Another often-quoted example is slavery: if enslaving one person benefits many people, can we condone it? The theme of sacrificing some to keep the wider social order is often described in art and stories, such as the short story The Lottery by Shirley Jackson, and The Hunger Games by Suzanne Collins.

Utilitarianism can also lead to conclusions that some intuitively would consider supererogatory. Supererogatory means that something is beyond doubt good, but at the same time we feel it asks too much of us. For instance, Peter Singer states the following about poverty: “If it is in our power to prevent something bad from happening, without thereby sacrificing anything of comparable moral importance, we ought, morally, to do it” (1972). This seems straightforward, but he illustrates it with a striking example. Let us suppose you walk next to a lake where a child is drowning. You are morally obliged to save the child. However, let us suppose you walk by a shop where they sell shoes and see a pair of expensive shoes you want to buy, which cost 100$. According to Singer, buying this pair of shoes is equivalent to letting the child drown. In fact, with that money, you could have saved a poor child’s life, for example, by investing in mosquito nets. For many, saving on shoes to donate the money would seem supererogatory.

Deontological ethics

The rules in rule utilitarianism (you may not steal, you may not murder, you may not lie, etc.) may look the same as the duties described in this paragraph when discussing deontological ethics. The most crucial difference is the reason why these rules should be followed. The rules in rule utilitarianism have to be followed because they will eventually benefit society. As we shall see in the following paragraphs, deontology asks us to follow the rules because it is our duty to follow them. In utilitarianism, the intention of the person who follows the rules is not essential. They may do good deeds unconsciously or because they enjoy telling the truth or abstaining from murder. However, for the deontologist, the rules must be followed out of a sense of duty—the intention matters.

Deontological ethics is primarily associated with Immanuel Kant (1724–1804). Deontology is about the rights and duties we have as individuals for others. Kant wanted to lay down a way of ethical reasoning based on rational procedures that would apply regardless of human beings’ desires or social relations. These moral principles would be the same for everyone. Briefly, his theory goes as follows: Kant assumes that each person has inherent dignity . Each person is rational and free to make their own law autonomously. This dignity and autonomy must be respected at all times. Hence, human beings should be treated as ends, not merely means.

According to Kant , morality is to act according to the categorical imperative. This means acting according to generalizable maxims or rules of conduct. Such rules bind every rational creature and are grounded in reason. For example, it may be that we would like to lie sometimes, but we cannot wish that ‘you are allowed to lie’ would become a universal law . These ethical laws are valid for everyone. They are universal and not specific to a particular context, in contrast with conditional hypothetical imperatives (‘if you want to be cool, you have to buy fashionable clothes’). (Kant, 1997)

Deontological ethics has good points. Ideas such as respect and autonomy are not obviously present in utilitarian thinking, although many people think they should take a central spot in the theory of morality. Utilitarianism values good consequences; good intentions are less important. Still, the fact that you do something because you feel it is your duty, regardless of the consequences, seems intuitively to be part of morality.

However, the idea of universality in Kantian ethics has been criticized by Charles Mills (1951–2021), who points out that, for Kant , the concept of a rational person did not generalize to women and people of colour. Mills contends that this issue is not just a historical anomaly: abstracting from race (Mills is a proponent of critical race theory ) excludes from morality the genuine consequences that racial oppression has had—and still has—on people of colour. The idea of ‘colourblind’ ethics perpetuates this oppression by abstracting away from the different starting positions based on race. Mills nevertheless still inscribes himself in a Kantian tradition—as the title of his paper, ‘Black Radical Kantianism’, indicates. For him, respect for the other should consider how they, as part of a minority group, were—and are—disadvantaged. Failing to do that creates abstract equality that will perpetuate inequality by entrenching disrespect for minorities and their practices (Mills, 2018).

Strictly adhering to the rules of deontology might also lead to counterintuitive conclusions. Think about the following scenario: your friend is being chased by a murderer with an axe. They are looking for protection at your house. The murderer knocks and asks you whether your friend is in the house. A strict Kantian would have to say that you cannot lie and must respond ‘yes’. It is sometimes also difficult to imagine how a categorical imperative can be used in policymaking. Kant would, for example, oppose euthanasia in all circumstances. Still, euthanasia is allowed in several countries (including Belgium) under certain conditions.

Moreover, we may also feel intuitively that emotions, not a mere sense of duty, are essential to morality. Who you would consider to be the most moral person in the following scenario: person A, who truly loves taking care of people and spends their time as a volunteer in a centre for the homeless; or person B, who would rather spend their free time watching Netflix but still volunteers in a centre for the homeless because they feel morally obliged? A strict Kantian might vote for person B. Still, we feel that emotions are essential. Maybe person A is the most moral because they have an exemplary character. Can duty in itself be a ground for moral action? Do we need something more, like an inclination to care for others?

The American philosopher Christine Korsgaard (born 1952) has added a dimension of sensemaking and personal values to deontological ethics (Korsgaard, 1996). She offers us a modern interpretation of Kant ’s thoughts. Therefore, she distinguishes between the ‘universal law ’ and the ‘moral law ’, whereby the categorical imperative is only a formulation of the universal law. It is not the source of ‘doing one’s duty’. The moral law prescribes content related to your identity, to your being an embodied creature in everyday practice. This does not mean that you are merely guided by desires. In the process of reflective enforcement, you choose to identify yourself with a particular principle or law. This presentation of yourself is your practical identity, a description that makes executing what you want to do worthwhile. You take up a role. What you think you have to do is a conception of what you are. Morality is about ‘being able to live with yourself’. In Korsgaard’s view, deontological and virtue ethics , which we will discuss later, are coming closer together.

We have seen that the central notion of a rational being in Kant ’s ethics could become problematic. For Kant, being a rational person grounds who has rights and who has not. Later deontological approaches have tried to extend that to other entities. Foetuses and people with an intellectual disability , for instance, come to mind. And what about other-than-human animals ? The contemporary philosopher Tom Regan (1938–2017) has applied a deontological approach to animal rights (Regan, 2004). He stated that animals also have interests, are ‘subjects of a life’, and have intrinsic worth. Hence, they are ‘somebody’ rather than ‘something’. Still, this approach can be considered speciesist, to some extent. We can imagine that dolphins, whales, and primates are people as well. But what about, for example, invertebrate animals? Are jellyfish part of our moral communities?

Taylor Swift : hardcore deontologist?

“Taylor Swift has made several statements and taken actions that suggest deontological ethical thinking, particularly around artists’ rights and ownership of their work. Her stance that artists should own their masters and her decision to re-record her albums reflects a categorical view that certain principles (like artistic ownership) should be upheld regardless of consequences. She has framed these positions in terms of absolute rights and duties rather than purely utilitarian outcomes.”

This is a statement generated by the LLM Claude AI in January 2025, in response to our request for an example of a deontologist in pop culture.

In 2021, following a dispute with her record label, Taylor Swift started releasing her old albums as “Taylor’s Versions.” More than remasters, these versions were a statement of the author’s independence in a musical industry where labels own most of the artists’ copyrights. In accordance with deontological trains of thought, Claude stresses that such principles should be upheld regardless of consequences. But is that really possible? Taylor Swift, one of the richest and most powerful artists, had the opportunity to claim this independence and rerecord her albums herself—a freedom most artists do not have. Swift also received higher royalties for her music as a result.

Reflect on this case and discuss:

What do you think of Claude’s stating that Taylor Swift is a deontologist?

From a deontological perspective, do (or should) rich and powerful people have higher duties ?

What would Kant have done (had he abided by his own principles) in Swift’s shoes?

Virtue ethics

Utilitarianism and deontology try to lay down formulas for what is good and evil (respectively, ‘the greatest good for the greatest number’ and ‘what you can want as a universal law ’). As such, they do not fill out specific prescriptions on how to act in concrete circumstances. Virtue ethics tries to do this. Virtue ethics was initially conceived by the Ancient Greek philosopher Aristotle (384–322 BC) in his Ethica Nicomachea. Also, in the Middle Ages, virtue ethics was an important line of thinking. For instance, Thomas van Aquino (1225–1274) reconciled Aristotle’s virtue ethics with Christian doctrine. He laid down seven virtues : belief, hope, love, wisdom, courage, temperance, and justice . In the twentieth century, virtue ethics experienced a revival with philosophers like Elizabeth Anscombe (1919–2001) and Alasdair MacIntyre (born 1929).

Being virtuous is having a specific sensitivity to what is right under specific circumstances. It is choosing the suitable (or golden) mean between two extremes. For example, a virtuous person is courageous—the middle ground between brutal, unthoughtful behaviour and cowardice. A virtuous person is modest, which is the middle ground between shyness and impudence. These virtues are habits rather than duties . They bring eudaimonia (happiness, the good life) to those who have them. You are virtuous by phronesis or practical wisdom. You acquire a virtuous character by being sensitive to a specific situation, by the judgement of character, by living in a society in which one can learn. Virtue ethics then emphasizes a moral character, which can be built through practice and education.

Virtue theory has specific good points compared to utilitarianism and deontology . To begin with, these other theories have been accused of being too legalistic, which means that too much weight is given to following abstract rules or principles while morality is also about building good character. Relatedly, utilitarianism and deontology do not have much to say about the content of moral principles. They claim that what is moral should be what benefits the most people (utilitarianism) or what reasonable people should want to be a universal law (deontology). Hence, they could be considered examples of thin moral theory . Virtue theory is a ‘thicker’ kind of morality, as concepts such as courage, modesty, etc. are not overlooked (Väyrynen, 2025).

Nevertheless, virtue ethics also has some shortcomings. Aristotle believed that leading a virtuous life would ultimately lead to a happy life (eudaimonia). For Aristotle, happiness and the good life were inseparably connected: the good is connected to life’s ultimate goal (telos). In the twenty-first century, this looks naïve. Moreover, virtuousness depends on proper education and training. Can those raised in dire circumstances who have missed the proper education and guidance still lead a virtuous life? Also, what is seen as virtuous can differ from culture to culture. Depending on where one lives, euthanasia can be seen as an act of mercy or as murder. How can virtue ethics deal with such different attitudes? Virtue ethics looks especially suitable for interpersonal relations, but how do you apply specific moral rules to specific circumstances? Virtue ethics tells you how to live, not necessarily what to do when confronted with a specific ethical dilemma.

The concept of virtue and similar concepts have been present in different cultures throughout history. For example, in the text Life on the Slippery Earth, Sebastian Purcell describes a similar concept in Aztec culture (Purcell, 2018). Unlike the individual-focused Western approach, Aztec ethics emphasize managing vices with the help of others and leading a socially rooted life. They saw life as fundamentally slippery, and whether you are happy is equally dependent on luck as it is on your own character. Therefore, the community is important to help you get up when you slip. Aztecs believed that virtue is fostered through community support and continuous moral education rather than individual character alone. They viewed the good life as one that is worthwhile and balanced rather than necessarily happy.

Care ethics

Care ethics is an approach to morality that deals primarily with interpersonal relations. It started as a feminist critique of ethics dominated by abstract principles. Carol Gilligan (born 1936) wrote a critique on the different stages of moral development in children laid down by moral psychologist Lawrence Kohlberg (1927–1987). These six stages begin with morality as mere avoidance of punishment—in accordance with social norms and obedience to the law—through to the sixth stage, when moral reasoning is based on abstract reasoning consistent with universal moral reasoning, reminiscent of the Kantian subject.

Before going into the theory, let us discuss a vignette that Kohlberg used in his experiments. The following dilemma was presented to children to test their reactions:

A woman was near death from a special kind of cancer. There was one drug that the doctors thought might save her. It was a form of radium that a druggist in the same town had recently discovered. The drug was expensive to make, but the druggist was charging ten times what the drug cost him to produce. He paid $200 for the radium and charged $2,000 for a small dose of the drug. The sick woman’s husband, Heinz, went to everyone he knew to borrow the money, but he could only get about $1,000, which is half of what it cost. He told the druggist that his wife was dying and asked him to sell it cheaper or let him pay later. But the druggist said: “No, I discovered the drug and I’m going to make money from it.” So Heinz got desperate and broke into the man’s store to steal the drug for his wife. Should Heinz have broken into the laboratory to steal the drug for his wife? Why or why not? (Gilligan, 1993, p. 25–32)

When eleven-year-old Jake was presented with this dilemma, he stated that Heinz should steal the drug. He used logic to calculate that the wife’s life was more important than the worth of the drugs for the pharmacist. However, when eleven-year-old Amy was presented with the dilemma, she had a different answer. She did not think Heinz should steal the money but should seek other ways to solve the problem, like borrowing the money. If Heinz steals the money, he may have to go to jail, and nobody would be there to take care of the wife. Hence, she did not approach it as a purely logical puzzle but instead as a narrative of relationships. Kohlberg scored her at a lower level of moral development.

However, in her book In a Different Voice: Psychological Theory and Women’s Development (1993), Gilligan questioned this hierarchy of moral development and stated that there are two kinds of moral voices. The masculine voice is more logical and individualistic, and the emphasis is on protecting the rights of people. The feminine voice emphasizes protecting interpersonal relationships and taking care of people. This is the care perspective. Both perspectives are equally good. One is not more moral than the other; they complement each other.

In the last decades, care ethics has become a popular ethical approach. Famous care ethicists include Joan Tronto (born 1952) and Nell Noddings (1929–2022). Critical issues in this approach include respect for the vulnerability of others, the importance of relations, and ethics as responding to a need. Some have considered care ethics a kind of virtue ethics (the caring person as a virtuous person, the interpersonal rather than abstract approach). It is an integral part of bioethics and medical ethics, and looking at ethical issues from a relational perspective is indispensable for good ethical decision-making. For instance, if we want to look at the ethics of prenatal screening and pregnancy termination, we should not only consider utilitarian arguments (who will benefit?) or deontological arguments (at what point in development does a foetus deserve respect because it has become an end in itself rather than a means to satisfy a parental drive?). It is also imperative to investigate the individual experiences of pregnant people. Hence, an approach that considers individual experiences becomes more important with care ethics. Care ethics has also been applied to animal ethics. Other-than-human animals are considered vulnerable beings we should care for and protect.

Some care ethicists have also received criticism as they would present caring as an intrinsic characteristic of women, which overlooks social influences on women’s behaviour. However, this criticism is no longer valid if both the logical approach to morality and the relational approach are disconnected from gender but are still seen as complementary aspects of human morality. Another criticism is that responding to someone’s vulnerability can conflict with respecting someone’s autonomy .

Care ethics , with its emphasis on relationality and personal relations, is popular among feminist bioethicists. It has been compared to other bioethical approaches, such as principlist frameworks that prioritize autonomy and other principles. Consequently, whilst some argue that an ethics of care may conflict with an individual’s right to autonomy in medical encounters, it is possible to view respect for autonomy as an integral aspect of care. Care ethics recognizes the importance of relationality and considers the right to self-determination from that perspective. For example, when it comes to euthanasia, a caring approach to autonomy entails empathetically engaging with the person making the request, making them feel supported in their decision, and understanding the concerns of those around them. This approach, championed by philosopher Eva Kittay , underscores the relationality inherent in life (Kittay, 2019). Care is a reciprocal process, allowing both those receiving and giving care to flourish . Moreover, those receiving care should implicitly or explicitly endorse the care provided for it to be truly caring. An ethics of care extends beyond virtue ethics for healthcare professionals and parents; it also contains a political dimension, as argued by scholars like Joan Tronto . In her book Caring Democracies, Tronto defines caring as follows:

On the most general level, we suggest that caring be viewed as a species activity that includes everything that we do to maintain, continue and repair our ‘world’ so that we can live in it as well as possible. (Tronto, 2013, p. 19)

This emphasis on caring clashes with the prevailing approach to policymaking and economics. For example, during the COVID pandemic, it became clear how important care-related professions are. At the same time, they are often undervalued and associated with low compensation. Care ethicists, including Tronto, advocate for reevaluating this perspective and recognizing the centrality of real people’s lives in politics. An ethic of care relevant to bioethics transcends human interactions and acknowledges the intricate interconnectedness between humans and various entities, encompassing other-than-human animals , microbes, and the environment. Maria Puig de la Bellacasa , in her groundbreaking work Matters of Care (2017), expands on Tronto’s notion of care as a complex, life-sustaining network, describing it as inherently ethical and political. Puig de la Bellacasa proposes a concept of posthuman care that surpasses interpersonal and human realms, perceiving care as a pervasive condition permeating the fabric and surfaces of the world. Therefore, care reflects a fundamental reality of human existence and our intricate entanglement with the larger world—an understanding also present in Indigenous knowledge and ecofeminism .

Conclusion

This chapter has introduced four moral theories—utilitarianism, deontology, virtue ethics, and care ethics. Rather than prescribing a one-size-fits-all approach, we emphasized the importance of understanding these theories as tools that illuminate different aspects of morality. Utilitarianism focuses on outcomes and maximizing well-being, but it struggles to measure suffering and can be used to justify harming minorities. Deontology, grounded in duty and rational principles, values intention and respect for persons but can lead to rigid or counterintuitive conclusions. Virtue ethics centres on character and moral development through habituation and context-sensitive judgement, offering a richer picture of morality but raising questions about cultural differences and applicability to specific dilemmas. Care ethics, emerging from feminist critiques, prioritizes relationality, vulnerability, and responsiveness to others’ needs, expanding ethical reflection beyond abstract rules to include lived experiences and interdependence.

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