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Is Driving Fossil-Fuelled Cars Immoral?

Rufus Duits asks when we can justify driving our carbon contributors.

In this article I want to suggest that much of the use we make of fossil-fuelled cars might be morally wrong, or at the very least ought to be subject to serious moral assessment. Rather than adopting just one kind of ethical framework, though, I will try to show that the non-essential driving of fossil-fuelled cars is morally questionable according to reasonable interpretations of four major contemporary approaches in moral philosophy: the doctrine of double effect, utilitarianism, contractualism, and virtue ethics.

Double Effect Driving

Driving a fossil-fuelled car (or even just turning on the engine) causes harms of many different kinds. It pollutes the air, exacerbating symptoms of cardiovascular diseases and releasing carcinogens; it intensifies greenhouse effects, such as climate change; it increases the risk of killing, injuring, and maiming people; it reduces the public space available for other uses; it generates noise pollution and stress; it maintains sedentary lifestyles; and so on.

I take it that, all other things being equal, causing harm is morally wrong. There is no plausible ethical framework that suggests that we ought to cause harm without further justification. But causing harm can nevertheless be justified within different ethical frameworks in different ways. We will look at four ways in which the harm-caused by driving fossil-fuelled cars might be justified.

Consider, for a baseline moral assessment, idling, where a car has its engine running without the car moving. It is illegal in the UK and elsewhere to idle your engine unnecessarily.

Few would deny that idling outside a primary (young childrens’) school is morally wrong, because of the harm the vehicle pollution causes the developing lungs of children, and any idling-released greenhouse gases exacerbate the speed and effects of climate change too. Of course, some idling occurs by accident – drivers are sometimes oblivious that their engine is still running while they are stationary. But it is incumbent on all of us to discern when we are in breach of a moral requirement, so that doesn’t count as an excuse.

But why is it wrong at all? Because it causes harm, albeit incrementally. But then, so does having the engine running when the car is moving. Clearly, if we sense a moral difference between idling outside a school and driving a child to school, we think these are different sorts of actions. Perhaps, for example, we think there is no overriding reason for idling, whereas we think there could be an overriding reason for driving a child to school. How, then, do we justify the harms caused by making journeys?

One way might be through the principle of double effect. Accredited to St Thomas Aquinas (1225-74), this principle states that although it is always morally impermissible to bring about a harm intentionally, it may be morally permissible to bring about harm as a foreseen but unintended consequence of a good action, if the harm of the double effect is proportionally less than the good intended. Morally neutral actions – actions with no moral value – cannot figure in weighing justifications for causing foreseen, unintended, but harmful effects. If the action itself is morally neutral, the unintended harm will always be an overriding reason not to carry out the action.

Idling can help reveal the workings of this principle. Suppose I claim that my intention in idling is to keep the heating on. The harm of pollution is a double effect, but it is not intended: even if fossil-fuelled engines did not produce air pollution, I would still run mine to keep warm.

Here, the harm is proportional (and so, justifiable) only if a greater harm will come about if the heating is switched off. We can easily envisage such cases: perhaps my elderly passenger will become hypothermic unless I keep the heating on. But usually in countries with largely clement weather, the proportionality will be off. Wanting to avoid being a bit chilly is understandable, but as a desire it has no moral value. In general, mere comfort and convenience are not morally valuable goals. In and of themselves, they are morally neutral. If they constitute my only justification, then they are morally outweighed by the harm I cause by idling. So it is not permissible for me to idle merely to avoid feeling a bit chilly.

This reveals a helpful distinction between two different kinds of reason-giving factors. It would be comfortable to keep the heating on. But no amount of mere comfort to me can outweigh any harm I do to others and the environment. It’s not the right kind of reason. To outweigh the harm I do to others by idling, I would have to point to a greater evil befalling me if I didn’t and merely being a bit chilly isn’t such a harm.

What about making a journey in a fossil-fuelled car?

First, are the harms the same or different? Some of them are the same: pollution, greenhouse gas emissions, etc. But there are additional harms to consider, too. Increasing the risk of harm to others without justification is morally impermissible even if no actual harm results. Driving a car around obviously increases risks of injury and death to pedestrians, other road users, and animals, than not driving a car around, especially in certain kinds of urban environments. And the greater the risk, the greater the good required to outweigh this harmful double effect.

In the driving case, just as in the idling case, certain factors might bring the harm well into proportion: driving someone to hospital due to a medical emergency, for example. On the other hand, again, it’s not obvious that considerations of convenience or comfort can straightforwardly bring the harm into proportion. Feeling a little lazy or lethargic isn’t the kind of moral reason that could justify driving a fossil-fuelled car a distance that I could easily walk.

Is it possible to draw a principled line between considerations that will and considerations that will not justify the harms of driving? Perhaps in theory; but in practice it is very difficult, because of the number of factors involved in our individual decisions about travel. For example: Weather – harm to my clothes? Distance – how far is ‘walking distance’? Do we have good reason for travelling? What alternative transport is available? Is it reliable? It might be easier, however, to apply some general rules of thumb to keep ourselves in the moral green zone. One such rule could be to choose the mode of transport that causes least harm as well as poses the least risk of harm. Another rule of thumb might be not to allow considerations of convenience and comfort to override factors that concern wellbeing and harm. Yet another rule of thumb might be to attempt to minimize the number of fossil-fuelled car miles.

It’s clear then that the principle of double effect can be used in some cases to justify driving a fossil-fuelled car despite the harm doing so causes. But it also seems clear that driving a fossil-fuelled car is not a morally neutral act: it requires adequate justification to be morally permissible. As far as the principle of double effect is concerned, this justification can be based only on certain kinds of reasons: the kinds that can bring the harms caused into proportion.

Basically, immorality is the point here
Ferrari 480 © Carlos Valenzuela 2019 Creatuve Commons 4.0

Problematic Car Calculations

Thinkers influenced by St Thomas Aquinas are known as ‘Thomists’. The doctrine of double effect is a Thomist doctrine, and, clearly it focuses on the foreseeable consequences of our actions. However, there are other ethical approaches that also assess the consequences of actions, including utilitarianism. Unlike the Thomist, utilitarian consequentialists believe it can be permissible to bring about harms intentionally if this will result in greater overall levels of happiness (or pleasure, or preference, or satisfaction, depending on the exact version of utilitarianism.) In this sense, the ends can justify the means. Note though that for both the Thomist and the utilitarian, the resulting harm has to be proportional to the good intended. For the utilitarian the end only justifies the means if the good of the end outweighs the harm of the means and if the harm of the means is necessary for the good of the end. But, according to the utilitarian, this can mean that my ends can justify me doing harms to you.

However, there are notorious difficulties for the utilitarian in calculating the relative moral weights to be assigned to different kinds of outcome. In the idling engine outside the school gates scenario, for instance, it is unlikely that the aim of a little extra comfort can outweigh the harm done by the pollution; but how do you work out the exact value of the comfort, and the exact cost of the pollution caused, in leaving your engine running? This problem doesn’t arise for the Thomist because they already have an idea of what counts as a moral good (which is traditionally determined by the precepts of natural law theory). But the utilitarian doesn’t. For them, anything that’s desired or even preferred counts on the moral scales. This can make utilitarianism very difficult to make sense of in practice. Suppose I just love the sound made by the engine of my new Ferrari. Suppose I just really want to impress the other parents and their children with its throaty growl. Is it now okay to idle outside the school gates, to rev my engine loudly?

No doubt some people reason that it is. But it seems clear to me that, contrary to what the utilitarian might be committed to thinking, this is not moral reasoning. I doubt that loving the sound my Ferrari makes would be a morally significant reason of any kind – and especially one that could potentially outweigh the harm I do to pupils’ lungs. And it is certainly not the case that I am morally obliged to rev my engine, even if I really, really love the sound it makes.

To make a consequentialist approach to these issues plausible, then, we require a prior specification of what counts as a moral reason. One suggestion that appears more plausible than counting any old preferences and pleasures, would be counting only objectively determinable physical or mental benefits and harms. The physical harm done to children’s lungs by vehicle emissions is objectively specifiable, regardless of any preferences of the people involved. The harm to one’s mental health of noise pollution is objectively determinable, too; and so on.

How do the objectively specifiable benefits and harms of driving fossil-fuelled cars in fact stack up? Again, the complexity of the factors involved make determining relative moral summations very difficult in practice, even if they’re possible in principle. In any case, given that the harms of driving are rarely (if ever) intended, the utilitarian’s rules of thumb in weighing up the moral pros and cons would be practically identical to those of the Thomist, by and large.

There is an additional implication of the consequentialist approach to moral decision-making that needs some attention. When small harms – such as many emissions of small amounts of greenhouse gases – are multiplied, the consequence can be a catastrophic harm – the aggregated harm to sentient creatures of a rapidly warming climate. This is the problem of cumulative harms. Suppose that, by utilitarian reasoning, my emission of a small amount of greenhouse gas is justified by the benefit accrued – getting my child to school on time. Then it is also justified like-for-like for the millions of other parents who do the same. But the cumulative potential catastrophic harm for everyone, and indeed for the entire planetary system, is neither intended by anyone, nor is it justified even by the cumulative benefit of millions of children arriving at school on time. So utilitarian decision-making appears unable to forbid some actions that can result in catastrophic cumulative harms.

Utilitarianism certainly isn’t the only kind of moral approach that struggles with the problem of cumulative harms. Even the most benign actions can have disastrous consequences given sufficient numbers of people doing them. Utilitarianism is, however, the only kind of theory for which the problem appears paradoxical: it appears paradoxical for a theory that evaluates actions based on consequences to be unable to rule out actions that cumulatively cause a disastrous consequence that no one would have wanted.

Regardless of the interesting theoretical problem this poses, anthropogenic climate change and air pollution are real-world cumulative harms, and these cumulative harms really are catastrophic. They are strong reasons for consequentialists to be vociferously opposed to fossil-fuelled driving. John Broome argues in Climate Matters (2012) that the butterfly effect applied to the changes to the Earth’s systems wrought by greenhouse gas emissions implies that even a short drive powered by fossil fuels could potentially cause very significant harm. There may, on this approach, be contexts in which fossil-fuelled driving is morally permissible, but the bar for the harms caused being justified is going to be high – much higher than we typically think. It is unlikely that, for example, driving a fossil-fuelled car to visit an elderly relative instead of staying at home would be justified if it can reasonably be expected that the emissions arising would cause a destructive weather event some time in the future. So, although the harms of driving appear initially to lend themselves to utilitarian justification, it might be the utilitarians who offer the most severe proscription of the burning of fossil fuels.

Driving Principles

Contractualism offers a different model of moral decision-making. Instead of weighing up costs and benefits, intentional or otherwise, contractualism – as proposed by, for example, T. M. Scanlon in What We Owe to Each Other (2000) – attempts to determine what actions are licensed by principles that no one could reasonably reject.

Take the idling case. I might be happy to sit in my car outside a school with the heating on and the engine running. But what principle would this action accord with? Perhaps something like: ‘Keep your fossil-fuelled engine running to stay comfortable even if there are children nearby’. Now, such a principle would be reasonably rejected by the parents of those children. What, they may ask, entitles you to put your comfort above the health of our children? Since this rejection of my principle is reasonable (at least it seems so to me), the idling action is proscribed.

Contractualism takes inspiration from Immanuel Kant’s injunction not to treat other rational creatures merely as means, but always also as ends in themselves. It interprets this injunction to mean that we should behave only in ways we can justify to other rational creatures – or in other words, in ways that they would be willing to license. What kinds of principles concerning fossil-fuelled driving could be reasonably justified to all, then?

It might be thought that any principle that licensed harm or that licensed behaviour that substantially increased the risk of harm could reasonably be rejected – in particular by those harmed or put at increased risk of harm. Any parent of a child who dies by being hit even by a car that’s being driven responsibly and legally has sound justification for rejecting any principle that permits driving at all. This could straightforwardly outlaw driving altogether.

Contractualists have responded to this kind of issue by considering the time at which agreement is sought. Take John Rawls’ famous ‘veil of ignorance’ thought experiment (A Theory of Justice, 1974). In this thought experiment, to ensure fairness, we must agree on a set of principles for a proposed society in advance of knowing what our own position in that society will be. In this specific case, we don’t know whether we will be the unlucky victims of a traffic incident. However, many people would be happy to face a low level of risk to themselves for the convenience of driving. So they might well endorse a principle that puts them in harm’s way to a certain limited extent, if at the same time it conveniences them.

But it’s difficult to imagine consensus around this. Thomas Nagel argued in his article ‘One-to-One’ (London Review of Books, 1999) that it may be impossible to formulate any set of principles that no one could reasonably reject, because of the different weights people place on aspects of their wellbeing. One person’s greatest joy in life might be driving through the city at night in an SUV; another person would well be prepared to sacrifice driving to clear the streets of traffic. Their reasons may be incommensurable – indeed, their respective accounts of the good life might be mutually unintelligible – so there may be no principle that both of them could reasonably accept.

I think considering the ethics of fossil-fuelled driving exposes some of the weaknesses of the contractualist approach, but my purpose here is not to offer a critique of contractualism. Yet I also think the twin threats of climate catastrophe and air pollution could engender unforced general agreement amongst rational, informed individuals, as it would not be possible for anyone to reasonably accept any principle that guided behaviour that potentially resulted in the collapse of Earth’s ecosystems and people suffering en masse. However, our current effectively unrestricted fossil-fuelled driving is exactly that kind of behaviour. Surely, every reasonable person would reject any principle which licensed such destruction.

Death Eruption
Death Eruption by Paul Gregory

Aristotle Takes The Wheel

In the Aristotelian tradition, moral decision-making is conceived quite differently. One general characterisation of Aristotle’s approach is that moral agents use practical wisdom to practise, develop, and embed as habits those character traits necessary for living a good, flourishing life. Here, the extent to which any given action is virtuous can be judged in terms of the extent to which it manifests virtues. So when it comes to transport choices, what would an ideally virtuous person choose?

Aristotle claims that virtuous action is acting “to the right extent, at the right time, with the right motive, and in the right way” (Nicomachean Ethics, Bk II, Ch.9, c.330 BCE). One way of simplifying this formula might be to express virtuous action in terms of appropriateness. In light of some conception of a life well lived, the ethical question is, ‘What is the most appropriate action in the given circumstances?’

Certainly, on such an account, many fossil-fuelled car journeys would turn out inappropriate. The car is often not ‘the right tool for the job’, given the extravagant energy investment it requires compared to public transport, say – and the total energy required to complete a journey is a relevant consideration when deciding what is the most appropriate way to travel.

According to Philippa Foot, a necessary property of a disposition being a virtue is that it combats temptation (Virtues and Vices and Other Essays in Moral Philosophy, 1978). In other words, virtues correct those human psychological tendencies that make it difficult for us to act well. If this is right, then mere convenience or comfort, appealing as they do to our dispositions to be lazy or selfish, don’t count as virtuous reasons for action. But there’s no doubt that these are often the kinds of explanations on offer for choosing fossil-fuelled motoring over other forms of travel.

Finally, it is worth briefly drawing attention to Rosalind Hursthouse’s attempt to formulate a virtue-based environmental ethic (‘Environmental Virtue Ethics’, Virtue and Action: Selected Papers, ed. Julia Annas & Jeremy Reid, 2023). She proposes wonder and respect as appropriate kinds of response to the natural world. On this view, to be virtuous requires living in such a way as to do minimum harm to the natural world. This would involve cutting one’s carbon footprint and reducing the pollution one generates, and thus is unlikely to license much of our fossil-fuelled car use. What are we to make of this approach, from our fossil-fuelled Western perspective? ‘Living or faring well’ (Nicomachean Ethics) seems today to be equated with critically damaging our planet’s life-support systems.

Travelling is embedded within human life across all cultures. As I hope to have shown, however, the means by which we travel are not morally neutral. It’s high time philosophers working in applied ethics began to systematically analyse them.

© Rufus Duits 2024

Rufus Duits teaches philosophy at St Paul’s School, London.

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