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Ethical Truth in Light of Quantum Mechanics

Iain King and Myles King contend that physics helps us understand ethics.

Criticising one of history’s most important-ever scientists can sound like a sketch from Monty Python: “OK, but apart from breakthroughs in optics, mathematics, mechanics, explaining gravity, inventing calculus, something about trigonometry, predicting how planets move, and other stuff that we don’t understand, what has Isaac Newton ever done for us?”

Newton’s work transformed science, and eventually, society. But Newton’s legacy comes with an ugly side: he inspired ‘physics envy’, which, in turn, led humanity to some truly dark places. ‘Physics envy’ is the desire to find Newtonian-type mathematical formulas or algebraic laws in other disciplines. Sometimes the endeavour is absurd, as when economists try to explain their economic opinions in algebraic equations. But when applied to psychology, history, class warfare, or evolution, thinkers with physics envy usually end up describing humans in dangerously oversimplified terms. Their theories would only work for model people – humans who have been stripped of their nuance and complexity. Moreover, as too many twentieth century tragedies have shown, when people become just elements in an equation, they can be treated as if they have no value at all.

Physics envy infected philosophy, too; in particular, ethics. Mirroring Newton’s Second Law that force equals acceleration multiplied by mass (F=ma), the Scottish philosopher Francis Hutcheson proposed that good equals the greatest happiness of the greatest number (G=gHgN). Jeremy Bentham adapted Hutcheson’s idea into what he called his ‘hedonic calculus’ – a phrase which draws deliberately on Newtonian mathematics. The Prussian philosopher Immanuel Kant plumped for a different type of formula to define what we should do: we should “Act only in accordance with that maxim through which you can at the same time will that it become a universal law.” So Kant was using the Newtonian idea of a universal law to tell people what to do. Both Kant and Bentham believed they had unlocked the secrets of moral philosophy as surely as the Cambridge professor had demystified the cosmos.

But are moral laws really like this – something as real as planetary motion, waiting to be discovered and defined?

It would certainly be helpful if they were, and if those discoveries were subsequently made, and the foundations of ethics at last established. All those testing moral dilemmas would melt away. Difficult decisions could be solved as easily as pressing the ‘equals’ sign on a calculator. People would only need to apply the right formula for the answer to be clear.

Certainly some moral positions do seem like absolutes. Genocide is truly appalling, and anyone who tries to say that it isn’t evil is beyond the pale. ‘Genocide is wrong’ is to us as certain as gravity. But many moral quandaries seem much more like a matter of opinion. Is it okay to wear a yellow shirt to a funeral? Or to crush a beetle underfoot when running for a bus? These sort of questions depend on taste and context. They’re still moral questions, but for each one the balance between convenience and causing offense is open to debate. We can agree to differ on these issues and remain friends.

Ethical Truth in Light
Ethical Truth in Light by Abigail Vettese, 2023
Image © Abigail Vettese 2023 Instagram: @theshapeofsanctum Website: abigailvetteseart.com

Clues to Moral Reality

One problem for those seeking a Newtonian formula for ethics is that it’s hard to see how ethical statements can be like other facts about the world. For instance, society has a huge influence on what is perceived as right and wrong. Even absolute taboos like genocide have been accepted in Ancient Rome, Rwanda, Nazi Germany, and elsewhere. How can we know we’re right about it now? After all, eating meat and burning fossil fuels – widely acceptable behaviours for most of human history – may well come to be seen as morally reprehensible in just a few years’ time.

Also, how do we detect right and wrong? They’re not like planets to watch in the sky, or apples which hurt when they fall on our heads. We can’t smell, taste, or hear moral values. Instead, we conjure them in our minds – just like things we imagine which don’t really exist. This means right and wrong apparently have more in common with the Tooth Fairy than with the mass, distance, and time with which Newton mapped out the world.

But if we look closer we can find five clues about how right and wrong operate, and they point in a very interesting direction.

First, when you label an action ‘right’, you are forced to label any identical actions ‘right’, too. Only if you can point out a morally significant difference is it okay to describe, say, one killing as an awful murder, and the other as an acceptable homicide. In theory, by saying a particular action is right or wrong, you’re determining how right an identical action is, even if that twin is many miles or centuries away.

Second, the labels of ‘right’ and ‘wrong’ only apply to certain things. An action can be good; as can be a state of mind or an intention; and outcomes can be compared in similar terms, some being fairer than others. But an inanimate object, like a chair, isn’t good or bad in quite the same (moral) way. When we describe art, engineering, or dental work as ‘good’, we are showing a different sort of admiration or assessment of it. It’s not usually a moral judgement.

Third, it’s only possible to develop a coherent form of ethics when we apply labels of good or bad to just a single type at a time – intentions, or actions, or outcomes. Many moral dilemmas arise when we mix these ways of judging. Bentham’s ethics, for example, offers a judgement for every decision, based solely on how happy people end up: for him, more happiness is always better. But his ethics seem odd when judged from the point of view of actions or intentions: would it really be right to force two innocent people to duel to the death if it made forty thousand spectators ecstatically happy? Twice as right with an audience of eighty thousand? It seems as if ethics can operate clearly in a single realm or dimension, but problems come when we shift from one dimension to another.

Fourth, how we think about right and wrong affects how we think about and behave towards people or things. You could pass a homeless person without a second thought; but when you ask yourself, ‘What’s the right thing to do here?’, you may well think and behave differently. You might first wonder whether the person deserves charity, or at least whether they should be shown some. Just thinking about the situation changes your attitude. To study a moral quandary is to affect it.

Finally, it’s not clear that right and wrong have any real place in the world at all anyway, because we might not have free will. Some argue that all our decisions are shaped by our evolution and the environment, for instance, or by previous physical events, and so it’s an illusion to think that we’re really making choices. If this view is correct, then we can’t really describe our decisions as ‘right’ or ‘wrong’: that would be like blaming the ocean for making the beach wet. Like the sea, if people are fully controlled by nature, it would be out-of-place to praise or blame us for our behaviour, because we didn’t really make a free decision to do it. The world made our decision for us, we might say.

Quantum Ethics

These five clues indicate that right and wrong are very odd things. Indeed, the Australian philosopher JL Mackie called moral values ‘queer’, and suggested they were so unusual it would be impossible to think of them as like anything else at all. But let’s look again at this list of how right and wrong operate in the world. We’ll see that, actually, they are much like something physicists have studied in thousands of experiments, two centuries after Newton.

All these five clues about ethics come straight from the quantum world. ‘Spooky action at a distance’ is what Albert Einstein called a phenomenon more dryly referred to as ‘quantum entanglement’. Investigations have shown that, when a pair of already-related quantum entities, say, photons, are separated, the characteristics of one are determined (and not just known) when observations discover the matching characteristic of its partner, irrespective of the distance between them. This ‘non-locality’ effect goes against all our intuitions – much as it went against Einstein’s, who remained sceptical about it until his death. But repeated tests have proven that this is how sub-atomic particles actually do work. Indeed, the 2022 Nobel Prize for Physics was awarded jointly to Alain Aspect, John F Clauser, and Anton Zeilinger, for finally proving this very thing.

‘Spooky action at a distance’ works for moral judgements, too: as we saw, judging something as ‘bad’ instantly applies that same label to identical situations or behaviours, however far away they may be. So a judgement in one place has an instant impact on a twin situation even if it is a great distance away, and there is no direct connection between the two.

Another similarity between quantum physics and ethics is the limit to the things we can label. Just as ethics only applies to certain things, there is a finite number of different sub-atomic particles to study. The exact number is debated (seventeen, or more?); but quarks, leptons, photons, and gluons would qualify, recently joined by the newly discovered Higgs boson. Ethicists disagree as vehemently as scientists; but most would accept right and wrong can be assigned to intentions, actions, and some specific qualities in outcomes, but not to most other things.

Quantum physics also shows that quantum-scale entities can behave like waves in some situations and like particles in others. Light, for example, can impact your retina as individual photons, like particles; but it can also come in waves which form interference patterns, leading to ‘wavy’ light and dark areas on screens after the light has been passed through narrow slits (just like the peaks and troughs of a sound wave which allow noise-cancelling headphones to work). The situation is similar in ethics, in which right and wrong seem to apply to actions in some circumstances (which Kant focussed upon), and elsewhere to a quality of outcomes (Bentham’s approach). In this way the ‘action-outcome’ duality (or in jargon terms, the ‘deontological-consequentialist’ duality) of right and wrong mirrors what is called ‘wave-particle duality’ in quantum physics. Then there’s Heisenberg’s Uncertainty Principle. The German physicist Werner Heisenberg proved that we can know the velocity of a subatomic wave-particle, or its location, but never both; and similarly with other pairs of quantum properties. Just so, in moral philosophy, we can often be sure that something is right according to its consequences, or by judging the actions, but not by considering both at the same time. We criticise someone for stealing (a bad action), or we praise them for giving money to the poor (a good outcome); but combine the two and our moral verdict is complicated.

Also, we have the observer effect. In quantum physics, as has been proven repeatedly, what and how the observer choses to observe will profoundly affect what is observed. Thinking about or observing an ethical decision will also affect our ethical choice profoundly. Accurate observer-unaffecting observation-based discovery, as practiced by Newton, is impossible for both.

Finally, quantum physics may help answer the conundrum of free will. Only at the human level might everything be predetermined by the environment, by genes; generally, by what has gone before. At the quantum scale, subatomic particles can spontaneously appear from nowhere. If choices in our minds spontaneously appear too, this might help solve the riddle of free will.

Right and wrong are very ‘queer’, just as Mackie said; but their share their queerness with subatomic particles in surprisingly similar ways.

Additional Weirdness

There are some other weird quantum effects which could have parallels in moral philosophy. Quantum tunnelling, for example, shows how subatomic particles can penetrate barriers in ways we wouldn’t expect (by passing through solid walls, for example). Does this offer lessons for how we should judge impossible-to-predict moral consequences?

So does quantum mechanics help prove that genocide is really wrong, or even help you decide what colour shirt to wear to a funeral, or whether it’s okay to tread on a beetle? Not directly. But it does tell us several things about the norms which prohibit mass killing, the fashion codes for solemn events, and the rules for trampling on insects. It tells us for instance that where a norm exists or a moral judgement is made, like a sub-atomic particle it will entangle identical situations elsewhere. Just to observe the norm is to be affected by it, and to affect the application of the norm in turn (even if we reject it). Some norms may only apply when we judge either actions or their outcomes, but not both. And scale matters: the norms which apply to our individual affairs may mutate into very different norms when many more people are involved.

Does all that take us towards the answer to the most fundamental question in moral philosophy, ‘What should we do?’

Perhaps if we understood quantum physics better, we might find the answer. The solution to the largest problems faced by humanity could be discovered in the secrets of the smallest things we know. The atom-smashers at CERN, or some other large hadron collider, might actually help us make the world a better place.

It seems that moral philosophers were right to have physics envy after all. But it shouldn’t be for Newtonian physics. Although his fancy formulas for gravity and calculus guided mankind very precisely to the Moon, they sent philosophers on Earth, including Kant and Bentham, in the wrong direction. If you want to know the secrets of right and wrong, quantum mechanics is the place to look.

© Iain King and Myles King 2023

Iain King is the author of the satirically-titled philosophy book, How to Make Good Decisions and Be Right All the Time. Myles King is a student at Sidwell Friends School in Washington DC.

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