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The Disunity of Utilitarian Psychology: Runaway Trolleys vs. Distant Strangers

Guy Kahane**, Jim A.C. Everett**,

Brian D. Earp, Lucius Caviola, Nadira Faber, Molly Crockett,

and Julian Savulescu

Last week, we invited people to find out “How Utilitarian Are You?” by filling out our newly published Oxford Utilitarianism Scale. The scale was widely shared – even by Peter Singer (who scored predictably highly). The Oxford Utilitarianism Scale does a pretty good job of measuring how well people’s views match up with “classical” utilitarians (think Bentham and Singer), which is the form of utilitarianism we used to anchor the scale. But that’s not all it does. It also teases apart two different dimensions of utilitarian thinking, tracking two ways in which utilitarianism departs from common-sense morality. Our new research recently published in Psychological Review links these two factors to distinct components of human psychology.

The first peculiar aspect of utilitarianism is that it places no constraints whatsoever on the maximization of aggregate well-being. If torturing an innocent person would lead to more good overall, then utilitarianism, in contrast to commonsense morality, requires that the person be tortured. This is what we call instrumental harm: the idea that we are permitted (and even required) to instrumentally use, severely harm, or even kill innocent people to promote the greater good.

The second way that utilitarianism diverges from common-sense morality is by requiring us to impartially maximize the well-being of all sentient beings on the planet in such a way that “[e]ach is to count for one and none for more than one” (Bentham, 1789/1983), not privileging compatriots, family members, or ourselves over strangers – or even enemies. This can be called the positive dimension of utilitarianism, or impartial beneficence.

What are the psychological roots of utilitarianism? Why does utilitarianism attract some people but strongly repel so many others? Psychologists have tried to answer these questions by using the now famous (or infamous, depending on your perspective) ‘trolley problems’. Many psychologists assume that by studying how people respond to these problems, we can shed light on the psychology of utilitarian decision-making as well as on the sources of resistance to utilitarianism. Because of this research, many people now associate utilitarianism with a cold and calculating response to trolley dilemmas: to be a utilitarian is to be willing to sacrifice an innocent person to save a greater number of lives. But since trolley dilemmas are concerned only with the issue of instrumental harm, they can at best only tell half of the story about the psychology of utilitarianism—and arguably the less important half.

Our goal was to develop an alternative psychological measure that is philosophically precise and accurately captures both dimensions of utilitarianism – not only instrumental harm but also impartial beneficence. Given this goal, we developed the Oxford Utilitarianism Scale based on a thorough analysis of the philosophical literature and external vetting by leading experts in utilitarianism and ethical theory.

To be clear, our aim was not to develop a test of the explicit views of these expert ethicists: their job was just to help us ensure that the scale items captured the right philosophical notions. Instead, our aim was to measure informal moral tendencies in the general population—the views of ordinary people who may have never heard of Bentham or Kant. By answering just nine questions, the scale can tell you where your intuitions fall on the dimensions of impartial beneficence and instrumental harm, as well as providing an overall measure of how utilitarian your intuitions are.

Nevertheless, the scale we developed does happen to work as a pretty good measure of the views of moral philosophers as well: unsurprisingly, they get an overall score that reflects their distance from classical utilitarianism fairly accurately: ‘hardcore’, uncompromising utilitarians score very highly on our scale, while Kantians score pretty low, as you can see in this graph of data from a sample of professional philosophers who filled out our scale after it was developed:

But this is where things get interesting. For moral philosophers, Instrumental Harm and Impartial Beneficence go hand in hand: Kantians largely rejected both, unqualified utilitarians strongly endorsed both, and other views fall somewhere in between. What we found, however, is that this is not the case in the general population. In ordinary people, these two subscales are only very weakly correlated: how you score on one barely predicts how you would score on the other.

In fact, these two theoretical aspects of utilitarianism appear to reflect distinct dimensions of moral cognition in the general population, each exhibiting a different psychological profile. For example, empathic concern, identification with the whole of humanity, and concern for future generations are positively associated with impartial beneficence but negatively associated with instrumental harm; and while instrumental harm is associated with sub-clinical psychopathy, impartial beneficence is associated with higher religiosity.

These findings challenge the widely held assumption that utilitarian decision-making is a unitary psychological phenomenon in the general population, let alone something based in a specific neural system, as some researchers have proposed. Things that go together neatly in the precise theories of moral philosophers may come apart when we turn to the psychology of ordinary people. In other words, ordinary people don’t normally engage in anything that can be usefully called ‘utilitarian decision-making’. But the way they approach moral questions may reflect, to a greater or lesser extent, different aspects of a full-blown philosophy of utilitarianism. This is what the Oxford Utilitarianism Scale measures—and this is why we advise researchers to focus on the distinct scores of each of the sub-scales rather than on the overall score.

A common objection to utilitarianism is that it is fundamentally at odds with human psychology. Our research suggests a more complicated picture. On the one hand, there seems to be a continuum between everyday ways of thinking about morality and the full utilitarian view. ‘Commonsense morality’ is not monolithic, and ordinary people have a range of views about instrumental harm and impartial beneficence—with some having little problem with sacrificing an innocent person for the greater good and others thinking about morality in a highly impartial and global way. Yet these two aspects of utilitarianism rarely go together. Someone who has deep emphatic concern for others may find the idea of Impartial Beneficence very attractive—yet at the same time recoil from the idea of Instrumental Harm. In fact, in our study we found that only a tiny minority of the general population is high on both sub-scales.

So those seeking to promote the philosophical doctrine of utilitarianism, like hard-core utilitarians, need to decide what they want to emphasize. By highlighting a tough-headed response to trolley dilemmas, torture, infanticide, or bestiality they may be putting off precisely those people who are already attracted to the idea that we should care equally about the welfare of all sentient beings on the planet. If utilitarians want to be ‘effective altruists’, perhaps they shouldn’t trumpet their tolerance for infanticide (under certain conditions) and other forms of instrumental harm.

What explains the striking difference between professional philosophers and ordinary folk? At this point we can only speculate. One possibility is that there is a deep theoretical connection between the two dimensions and that once people begin to reflect on morality in a systematic way they are led to either accept or reject both. But it’s not obvious that if you care about everyone’s welfare equally you must also be willing to violently sacrifice the few for the many, or vice versa.  In fact, some ethical theories do seem to accept one but not the other, and in doing so appear to be perfectly coherent (for example, some forms of Christianity and Buddhism tell us to care about the whole of humanity, or even all sentient beings, without condoning instrumental harm).

Perhaps the current landscape of moral philosophy neglects important theoretical options and is therefore unattractive to people who would score high only on one dimension. Another possibility is that people make the journey towards utilitarianism from different starting points. Some people may start out suspicious of various commonsense prohibitions on harm (or for that matter sexuality) and only gradually come to accept the idea that we should treat everyone’s welfare equally. Others may start with deep sympathy for all sentient beings and reluctantly come to accept that we should use any means to promote the greater good. These two groups of people may hold similar moral views but have profoundly different psychological differences.

We still don’t know the answer to these questions. The important lesson, though, is that there is more to utilitarianism than pushing people onto train tracks. Psychologists have spent over 15 years studying what we call Instrumental Harm. It’s time to begin to study the positive core of utilitarianism, the idea of Impartial Beneficence. Or better: to study both, and to begin to clarify their relationship.

If you’re interested in reading more about the scale development and our two-dimensional model, the paper is open access and can be accessed here. If you’re interested in using the Oxford Utilitarianism Scale in your own research, the full items along with detailed scoring instructions, a prepared Qualtrics survey of the scale, and an R script for data analysis can all be found here. And if you are teaching a course on Utilitarianism, the scale itself and the instrumental harm and impartial beneficence subscales can be quickly taken here. They are a great way to start discussion of what Utilitarianism is and students can find out how utilitarian they are.

Kahane, G**., Everett, J.A.C.**, Earp, B.D., Caviola, L., Faber, N.S., Crockett, M.J., & Savulescu, J. (In Press). Beyond Sacrificial Harm: A two-dimensional model of utilitarian psychology. Psychological Review. Doi: 10.1037/rev0000093

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