A Glass of Water Has No Final Truth: Quantum Mechanics Forces Us to Give Up the Single Perspective
Physicist Carlo Rovelli says the deepest lesson of quantum mechanics is not new particles, but that the Enlightenment dream of a single objective reality independent of the observer does not hold — reality is many perspectives that enrich one another but never converge.
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A glass of water has no final version
Rovelli opens with a glass of water the BBC provided: you look from one side, I look from the other, you wear glasses, I see a different colour. This glass of water can be a physical object (mass, velocity, position), it can be temperature and pressure, it can be the chemistry of H2O plus floating bits, it can be the global economy of being bottled in Italy and shipped to England, or it can just be ‘we want to drink it’. His argument is: all these perspectives are real, none exhausts another, none contradicts another, and there is no ‘ultimate glass of water’. This is anti-Platonic — he does not accept a distinction between a ‘level of appearances’ and a ‘fundamental level’.
— Carlo RovelliWe have not yet digested quantum mechanics
Rovelli says what he is describing is not borrowed from philosophy but grown from inside physics. Physicists ran into quantum phenomena; quantum mechanics is an enormous revolution, but ‘we have not yet digested quantum mechanics’ — the newspaper stories about experiments that ‘confirm what I learned in a textbook in the 1970s’ show precisely that we do not yet truly believe it. Take quantum mechanics seriously and what it says is this: the Enlightenment dream of ‘describing reality completely, determinately, clearly, independently of the observer’ does not hold. The observer here need not be a human; anything that interacts with something counts.
— Carlo RovelliThe most fundamental reality is not more objective
Rovelli turns it around: the reality at the most basic level physics can reach is in fact not essentially different from the reality Lavinia deals with in poetry, or the characters in James's play deal with in economics — both are realities that allow different views, not a reality that is ‘absolutely objective underneath’. So quantum physics is not that hard; it has simply not been digested. The concrete physical phenomena are of course very complex, but poetry is complex and economics is complex too.
— Carlo RovelliScientists have always used metaphors
Rovelli says the words Lavinia uses could be lifted line by line into his book. What is an electron? ‘It is a grain, a grain of sand, but it is not really a grain of sand.’ Why is an electric field called a field? Because it is ‘a bit like a field in the countryside’. We think through metaphor, by taking old concepts apart and putting a piece of each together into a new concept. The goal is not to arrive at a final, perfect description of reality — a century ago we thought we could, but it does not work — but to gain better understanding, better ways of navigating reality. He adds a crucial qualification: admitting that everything has a perspective does not mean all perspectives are equivalent, nor that there is no better and worse; it is only that the hope of ‘arriving at the final correct story about reality’ is empty — not unreachable, but meaningless.
— Carlo RovelliSeeking the ultimate morality is itself wrong
Rovelli turns from ‘complexity’ to ‘value’: if you ask ‘what is the ultimate definition of good and evil, what is universal ethics’, he thinks this is itself a morally and ethically wrong approach. Our morals and values are powerful, important and indispensable not because they are outside us, but because they are inside us, and therefore equally perspectival. This passage connects directly to James Graham's play — whose first line is ‘what is a good life’.
— Carlo RovelliDo not be afraid to learn a jargon
Lavinia Greenlaw argues for embracing jargon: not everyone has to learn it, but if you are genuinely interested in something, do not be afraid to learn its language — a mechanic has to learn the names of parts, a surgeon has to learn the names of parts, a poet has to learn too. It lets you see more clearly, and it lets you see where something has gone wrong. She admits jargon can be exclusionary, but ‘that depends on the context in which you use it’, and ‘you can perform difficulty, poets and poems are probably very good at that, but that is not what difficulty means’. She gives the example of poems on the underground: before everyone looked at their phones, people would read a poem first and only then realise they were reading a poem — that kind of engagement is far more direct and confident than sitting down and being told ‘now you are going to read a poem’.
— Lavinia GreenlawFriction is treated as a problem to be solved
James Graham says modern culture fetishises ‘efficiency’ and strips out every layer of difficulty as friction. He gives a concrete image: emailing himself a script to save it, a prompt pops up — ‘this is a long document, shall I summarise it for you?’ — and his reaction is ‘how rude, I want you to sit inside it and read’. He connects back to Bloomsbury and Keynes: meaning is discovered precisely in the friction, in the difficulty, in the process. He also says the collapse of reading is despairing, because reading demands personal investment, and today that investment is treated as a problem to be solved rather than something to be celebrated.
— James GrahamWar refuses to acknowledge complexity
Rovelli uses International Peace Day on 21 September, and remarks by the UN Secretary-General and the Pope, to connect the argument about perspectives to war: war is to a large extent driven by greed and power games, but it always wraps itself in hypocritical narratives — there is only one truth, only one good, we are the good ones, they are the bad ones, we tell the truth, they tell lies and propaganda. So war is built on a total refusal to be prepared to accept complexity, perspectives, and worldviews different from our own. The host Adam Rutherford immediately offers a counterexample: we also always need simplicity; if you embraced difficulty and acted scholarly all day, you might get nothing done and enjoy nothing. Lavinia's response pulls the topic back to rhetoric: language therefore matters more than ever, and poetry and poetics can teach people to argue.
— Carlo RovelliBuying paintings for twenty thousand pounds in wartime
James Graham tells the most gripping piece of history in his play: in the First World War, Britain had just gone from being the world's creditor to a debtor; Keynes, as a junior adviser at the Treasury, asked Treasury officials and the Permanent Secretary for £20,000 to go to Paris to buy paintings, because Edgar Degas's collection was coming up for auction. At the time all money was flowing to armaments and the war. No one knows what he said at that meeting, so the playwright gets to write his words for him. Graham says the ‘absurdity’ of the case is precisely its power: if there was money left over, what should be done was to buy a few paintings and put them in the National Gallery, because in the future they would be both an asset on the government's balance sheet and an asset that gave the nation something beautiful to look at after the war — ‘if peace is not about creating things that make people happy in the future, then what is it?’
— James GrahamTwo men on a church roof watching for incendiaries
The opposition between Keynes and Hayek is written by Graham as the core of the play: Hayek represents the Adam Smith tradition of the ‘invisible hand’ — let it be, it will self-correct, and intervening with imperfect human hands is dangerous and reckless; Keynes represents the interventionist mixed economy of the postwar consensus from 1945 to 1979. The two did meet, and one of those occasions was during the Second World War when both were on the roof of the chapel at King's College, Cambridge as fire watchers, entirely by chance, watching the Luftwaffe fly over looking for incendiaries. No one knows what they said that night, and Graham says this is a gift to a playwright, so he wrote their dialogue: Keynes says ‘Hayek, without imagination, how do we dream a new world’, and Hayek replies ‘You do the dreaming, Mr Keynes, I like to stay awake’.
— James GrahamIn their own words · checked verbatim
So I think the main thesis of my book is that all these perspectives are all real, neither exhaust any other one, neither contradicts any other one, and there isn't an ultimate glass of water.
Carlo Rovelli4:11
We haven't yet digested quantum mechanics.
Carlo Rovelli6:13
It only means that the hope of getting to a final correct story about reality, it's an empty hope because I would say it's not something unreachable. It's something meaningless.
Carlo Rovelli11:26
If we ask the question, what is the ultimate definition of good and bad? What is the ultimate morality, the ultimate ethics, the universal one? I think we are doing something morally wrong, ethically wrong.
Carlo Rovelli12:27
And again, back to my people, the Bloomsbury's and Keynes, it's in the friction, it's in the difficulty, it's in the process that you discover meaning.
James Graham23:57
To which Hayek says, well, you feel free to dream, Mr. Keynes, I like being awake.
James Graham38:37
I think progress comes in the moment in which we realize that reality is more complicated than the way we see it.
Carlo Rovelli40:46
Figures
| Sum Keynes asked the Treasury for to buy paintings in wartime | £20,000 | 32:29 |
| The war during which Keynes and Hayek served as fire watchers | the Second World War | 37:37 |
| The span of years of the Keynes–Hayek opposition | 1919 to 1945 | 39:38 |
| International Peace Day | 21 September | 26:05 |
Glossary
- anapaestic decameter
- A metre of two unstressed syllables followed by one stressed syllable, repeated five times; Lavinia jokes when giving an example that she may have got it wrong.
- iambic pentameter
- The basic metre of English poetry: one light syllable followed by one heavy syllable, repeated five times.
- Bloomsbury Group
- A group of artists, writers and philosophers in early twentieth-century Cambridge and London; Keynes was a member.
- friction
- In product and writing contexts, the resistance involved in using or understanding something; James Graham objects to treating it uniformly as a problem to be eliminated.
How to listen
Founders and investors interested in philosophy of science, interpretations of quantum mechanics, and the intellectual history of Keynes and Bloomsbury; people looking for judgment frameworks of the ‘perspective rather than single answer’ kind.
The podcast ads around 29:16 and the programme trailer at 42:50 can be skipped.