Ignorance: 2. The Limits of Knowledge

Summary

Podcast Summary: "The Long History of... Ignorance: The Limits of Knowledge"
Podcast: Rory Stewart: The Long History of...
Episode: Ignorance: 2. The Limits of Knowledge
Host: Rory Stewart, BBC Radio 4
Date: July 11, 2024

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Episode Overview

In this episode, Rory Stewart explores the profound limits of human knowledge, challenging the popular belief that the world is becoming ever more knowable and predictable. Through a blend of philosophical reflection, expert interviews, and personal anecdotes, Stewart reveals how certainty is often an illusion and how ignorance can have both destructive and creative consequences. The narrative journeys from the communal nature of knowledge, through the failures of grand projects (like Afghanistan), to the troubling limits in science, probing both the societal and cosmic scale of what remains unknown.

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Key Discussion Points & Insights

1. The Illusion of Certainty and the Division of Knowledge

[00:54–03:53]

• Rory Stewart sets the scene with the famous framework: "known knowns, known unknowns, and unknown unknowns" (01:07), inviting listeners to consider how easily we overestimate what we truly know.
• The division of “epistemic labor” underpins progress. Rowan Williams notes, “We have advanced as a species by a division of epistemic labor. So we have people who specialize in different fields, and we access them as we need.” (02:23)
• Merry Beard and Daniel Denicola argue knowledge is essentially communal and not for the individual alone. There’s overvaluation of self when we insist on knowing everything:

  "I have to know a man who does, or a woman." (02:42, Guest Academic)

2. The Pathos and Limitations of Specialization

[03:53–04:34]

• Stewart reflects on relentless specialization:

  “You know more and more about less and less and end up knowing everything about nothing.” (03:58)

• There is a tragedy to knowledge: granular certainty is gained at the cost of broader understanding.

3. Knowledge Failure in Public Policy: The Afghanistan Example

[04:34–07:23]

• Despite immense data and research, Western intervention in Afghanistan misunderstood local realities:

  “We seem to have accumulated more knowledge about Afghanistan than any previous generation. But… all this knowledge… did not seem to help us understand Afghan communities at all.” (04:54)

• Nicholas Gruen critiques technocratic arrogance:

  “We’re completely in our own heads... The question is, how relevant is this to Afghanistan? And the answer is, we don’t know, but we just assume that we do know.” (06:33)

4. Ignorance and Exclusion in Governance and Science

[07:23–09:42]

• Stewart admits, as a government minister, knowledge gaps were "stark and disturbing." (07:23)
• The community perspective is often overlooked:

  “We're trying to get across the technical perspective and the community perspective. The government legislation doesn't have any of that community element to it.” (08:24, Guest Academic)

• Science frequently reproduces bias (e.g., most genetic studies focus on European ancestry, limiting universality).

  “It is showing that what you’re achieving is limited and doesn’t have universal benefit.” (09:42, Guest Academic)

5. Dangers of Misapplied Knowledge: From Eugenics to Environmental Harm

[09:51–13:50]

• Scientific advances can have dark outcomes (e.g., eugenics contributing to the Holocaust):

  “Scientific breeding, the gradual elimination of inferior types and inferior races was just part of a liberating scientific project.” (10:13, Rowan Williams)

• British politicians easily embraced flawed “race science” due to both political temptation and misplaced trust in science. (10:22–10:58)
• Large-scale scientific projects (like nuclear testing) cause harm long after their initial justification:

  “2.4 million is the claim from International Physicians for the Prevention of Nuclear War.” (11:41, Expert)

• Ordinary people (farmers, indigenous Americans) often noticed harms first, but their insights were overlooked.

  “They could see that something was up. But that news did not manage to really filter out more widely.” (13:22, Expert)

6. Ecological Simplification and the Perils of Reductionism

[13:22–14:41]

• James C. Scott's example: German forest monocultures ignored the complexity of ecosystems, leading to their collapse.
• Overly narrow focus destroys unseen value and complexity.

7. The Myth of Linear Scientific Progress

[14:41–16:42]

• Science, especially natural science, is idealized as building “certain” knowledge piece by piece, but great advances often depend on ignorance, imagination, and lucky insight:

  “Most of the great discoveries of mathematics and science were made by leaps of intuition and by insights of imagination.” (15:34, Ian McGilchrist)

• Progress often comes from questioning seemingly obvious truths (e.g., Copernicus challenging geocentrism). (16:08, Carlo Rovelli)

8. The Scale of Our Ignorance: Physics, Biology, and the Universe

[16:42–19:33]

• We know only a fraction about reality:

  “We know how our bodies are made... But that only comprises like 5% of the stuff in the universe.... We are staggeringly ignorant about the nature of the universe.” (16:55–17:03, Daniel Weitzen)

• Basic phenomena (how brains or genes work, space and time) remain unsolved. (17:35–18:04)
• Even in quantum mechanics, our best models are sometimes contradictory or nonsensical:

  “In the morning... relativity... Everything is deterministic. In the afternoon... quantum... Everything is discrete, is indeterministic… they were giving me a totally incoherent picture of the world.” (18:51, Carlo Rovelli)

9. Metaphors, Limits of Mind, and the Language of Science

[19:33–21:46]

• Our understanding is often limited by the metaphors and language we have.

  “We create a sort of ecology of metaphor. This is a world in which we're going to need an awful lot of verbal resources to cope.” (20:25, Rowan Williams)

• The human mind may ultimately be incapable of grasping some truths:

  “We are inside nature and we're looking from the inside... If we view ourselves like that, then this narrative [of perfect knowledge] becomes a little bit meaningless.” (21:14, Carlo Rovelli)

• Famous quotation: “If you think you understand quantum mechanics, you don't understand quantum mechanics.” (21:38, attributed to Richard Feynman by Stewart)

10. The Fish and the Turtle: Limits of Communication

[22:19–23:13]

• Martin Palmer shares a Buddhist story illustrating that without direct experience, explanation fails:

  “I can't [explain what land is like]. You have no experience on which to build an image.” (22:46, Martin Palmer)

11. The Universe as an Endless Puzzle

[23:13–24:10]

• Quoting Douglas Adams, Rowan Williams suggests that any complete answer to existence would only be replaced by something more baffling:

  “There is a theory that if anyone ever finds out why the universe is here and what it is for, it will instantly be replaced by something even more bizarre and inexplicable. There is a second theory that this has already happened.” (23:23, Rowan Williams)

12. Chaos, Chance, and Probabilistic Reality

[24:10–26:49]

• Even deterministic systems (like rolling dice) are too sensitive to initial conditions to be predicted—basis of chaos theory (24:10).
• Deeper, quantum-level events are fundamentally probabilistic, not deterministic (25:09).
• Ian McGilchrist emphasizes that life itself “exists at this edge between order and disorder… There needs to be a degree of order and... unpredictability... The cosmos appears to be creating all the time.” (26:05–26:49)

13. Humility and Ignorance as Virtue

[26:49–28:38]

• Stewart closes with the core lesson:

  “We are often far more ignorant than we would like to acknowledge… Ignorance is a lesson in humility.” (26:49)

• The next episode promises to turn ignorance—from a limitation to a source of creative possibility.

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Notable Quotes & Memorable Moments

• “You know more and more about less and less and end up knowing everything about nothing.” — Michael Ignatieff quoted by Rory Stewart (03:58)
• “We're completely in our own heads... The question is, how relevant is this to Afghanistan? And the answer is, we don't know, but we just assume that we do know.” — Nicholas Gruen (06:33)
• “I was beginning to realize how very little I knew and how very little I would ever know, and how often the knowledge that mattered was not in libraries, but in the lived experience of local communities.” — Rory Stewart (07:23)
• “Most of the great discoveries of mathematics and science were made by leaps of intuition and by insights of imagination.” — Ian McGilchrist (15:34)
• “If you think you understand quantum mechanics, you don't understand quantum mechanics.” — Attributed to Richard Feynman by Rory Stewart (21:38)
• “We create a sort of ecology of metaphor...it's not so much that we're looking for a final map of the universe...as that we're looking for ways of finding language we can just about manage to sustain...” — Rowan Williams (20:25)
• “There is a theory that if anyone ever finds out why the universe is here and what it is for, it will instantly be replaced by something even more bizarre and inexplicable...” — Douglas Adams via John Lloyd and Rowan Williams (23:23)
• “Ignorance is a lesson in humility.” — Rory Stewart (26:49)

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Timestamps for Major Segments

• 00:54–03:53: Introduction; nature of knowledge, communal vs. individual knowing
• 03:53–04:34: Specialization and the tragedy of lost breadth
• 04:34–07:23: Afghanistan policy and hubris of knowledge
• 07:23–09:42: Gaps in government knowledge and scientific biases
• 09:51–13:50: Eugenics, misuse of science, and environmental monocultures
• 14:41–16:42: The myth of linear scientific progress
• 16:42–19:33: Limits of understanding in physics, biology, quantum mechanics
• 19:33–21:46: Metaphor, mind, and language in science
• 22:19–23:13: Buddhist parable about fundamental limits to explanation
• 23:13–24:10: “The universe is stranger than we can suppose” (Douglas Adams)
• 24:10–26:49: Chaos theory, probability, and cosmic unpredictability
• 26:49–28:38: Closing thoughts on humility and a preview of the role of ignorance in creativity

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Tone and Style

Stewart’s tone is reflective, questioning, and subtly ironic. The discussions are rich with historical and scientific context, while the many voices interject with academic, philosophical, or personal perspectives, contributing to a tapestry of humility-inspiring uncertainty. The episode encourages listeners to rethink their confidence in both the powers and the scope of human knowledge.

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Conclusion

This episode powerfully argues that our understanding—across society, science, and the universe—is vastly more limited than we care to admit. True wisdom, Stewart suggests, lies in humility before the unknown. The stage is set for the next episode’s exploration of how not-knowing can be a wellspring of creativity.

Transcript

[Advertisement Voice]

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[Rory Stewart]

BBC Sounds Music Radio Podcasts A particular view of knowledge has come to dominate the modern world and delivered extraordinary discoveries and innovations.

As we know there are known knowns. There are things we know we know.

But in this episode I want to tell a more uncomfortable story.

We also know there are known unknowns. That is to say, we know there are some things we do not know.

I want to consider how often we go astray when we apply this knowledge to the real world, how little we actually know.

There are also unknown unknowns, the ones we don't know we don't know.

How certainty about the world is an illusion. The Long History of Ignorance from Confucius

[Guest Expert / Academic]

to QAnon

[Rory Stewart]

Episode 2 the Limits of Knowledge we are transfixed by the idea that as humans, we know more and more, that the frontiers of knowledge are advancing all the time, and that there will soon be nothing important left to know. Hundreds of thousands of specialist scientists are each working a way to fill in all the gaps in the building of knowledge, like worker bees in a vast, coordinated hive. It's a humbling vision.

[Rowan Williams]

We have advanced as a species by a division of epistemic labor. So we have people who specialize in different fields, and we access them as we need.

[Rory Stewart]

As the philosopher Daniel Denicola and the classicist Merry Beard observe, human knowledge is not individual, it's communal.

[Guest Expert / Academic]

We need some people who do know it. You don't have to take the whole weight of that responsibility on yourself. Nor do you, Rory. You don't really need to know. We need people like me who read a lot of Latin, and we need people, you know, who know about quantum physics and we can actually share the tasks out, I think. And there is something a little bit kind of overvaluing of the self to say I have got to know everything. No, I don't have to know everything. I have to know a man who does, or a woman.

[Rory Stewart]

As we add knowledge to knowledge, we know far more about some aspects of the world. Our knowledge of medicine, of evolution, genetics and the universe itself is incomparably advanced on that of the very best educated people in the past. Almost everything we see and encounter is now the subject of yet another Wikipedia article linked to hundreds of thousands of more such articles. In ever narrowing rabbit holes and burrowing down these rabbit holes are narrower and narrower specialists.

This is the pathos of intelligence, it seems to me through time.

The Canadian academic and politician Michael Ignatieff.

You know more and more about less and less and end up knowing everything about nothing. The pathos of specialization. There's a very human tragedy that accompanies knowledge, which is that we achieve certainty about little things at the price of a. Of a broader grasp.

There's a paradox here. On the one hand, modern governments collect vast amounts of data, processing it at ever faster speeds, and seem to know more about the world than ever before. On the other hand, there are still catastrophic results.

[Rowan Williams]

We will not falter and we will not fail.

[Rory Stewart]

Peace and freedom will prevail. I experienced this in Afghanistan. Both walking across the country and later working there. The US government employed an army of researchers and social scientists. This includes deepening ties of trade, commerce,

strengthening institutions, development, education, and opportunities for

for all Afghans, men and women, boys and girls. We seem to have accumulated more knowledge about Afghanistan than any previous generation. But when I returned to Kabul and worked as a British diplomat, I saw how all this knowledge, which we, the international community, had accumulated, did not seem to help us understand Afghan communities at all. As Afghans stand up, they will not stand alone. The United States and the world stands with them. I remember vividly hearing in my first meeting after I finished the walk that every Afghan was committed to a gender sensitive, multi ethnic centralized state based on democracy, human rights and the rule of law. And thinking I didn't even know how to translate that into language which my hosts could understand. And that this claim of knowledge and others like it were right at the very heart of a project that ended up spending over $1,000 billion, costing tens of thousands of lives, and ultimately achieving almost nothing.

[Ros Atkins]

The Taliban is in control of Afghanistan, the country's president has fled, and Western countries are scrambling to get people out. And this took the US by surprise.

[Rory Stewart]

I put this to the Australian economist Nicholas Gruen. I noticed that there were very, very confident people selling a strategy for nation building. And they would say things like, you know, we're going to sort out Afghanistan, we're going to end corruption through transparent, predictable and accountable financial processes. And at first that sounds really smart, and then you realize that that's just a description of what doesn't exist. It's not a plan for getting there.

[Nicholas Gruen]

Yeah. And it's a description of what to some extent exists where we come from, and which took hundreds of years of acculturation, political struggle, disasters, mistakes to get it in the imperfect state that it's in for us. The other thing is that we're completely in our own heads. What we're doing is we're simply relying on what we know. And the question is, how relevant is this to Afghanistan? And the answer is, we don't know, but we just assume that we do know. Unless it just happens again and again. You can take it any, any important political issue, public issue, really, and you'll have the highly educated upper middle class and they'll be in their own heads.

[Rory Stewart]

Knowledge had become more complicated. Knowledgeable people began to seem more ignorant and the ignorant more knowledgeable. I call the Secretary of State, Rory Stewart, to move. When later I became a British government minister, the gaps between what we knew and what we claimed to know became even more stark and disturbing. We will be reporting in a formal report after this debate in Parliament to the un, and I hope this debate in Parliament will help inform some of the report that we're sending into the un. I was beginning to realize how very little I knew and how very little I would ever know, and how often the knowledge that mattered was not in libraries, but in the lived experience of local communities. I saw this very clearly when I became the minister responsible for water in the UK government.

[Advertisement Voice]

Just 16% of England's waterways are rated as having a good ecological status.

[Ros Atkins]

The governance target of 77% looks rather ambitious. Charlotte Sawyer is member of the Conham

[Advertisement Voice]

Bathing Group at Conham river park in Bristol.

[Guest Expert / Academic]

We're trying to get across the technical perspective and the community perspective. The government legislation doesn't have any of that community element to it. They don't use local data, local knowledge. And we're trying to use the voice and the knowledge of the people because we're the people who love the river, we live around the river. We see and unfortunately smell all the things that are going wrong.

[Rory Stewart]

Many of our democratic systems are built on the pretence that the central government or someone like me as a minister, knows best. Our whole parliamentary system expected me as a new minister who'd barely visited Africa, for example, to answer fluently on 42 African countries. And even when we're trying our best to look objectively and scientifically at a problem, we're often in fact simply embedding prejudice. This can be true even in drug development.

[Advertisement Voice]

There are these genome wide association studies.

[Rory Stewart]

Annette Martine is a philosopher at the University of Illinois.

[Guest Expert / Academic]

And these studies have been predominantly done on people of European descent. And further, when you're now doing future studies, it's easier to build on existing coh and so the gap kind of persists.

[Advertisement Voice]

That's not exactly casting doubt on the

[Guest Expert / Academic]

methodology or the result, but it is showing that what you're achieving is limited and doesn't have universal benefit or impact.

[Rory Stewart]

The application of scientific knowledge to human societies has brought great improvements in human lives, but it has also had devastating consequences for humans and for the world itself. Scientific discovery in the 19th century, for example, encouraged the idea of eugenics or race science, which contributed to the Holocaust. I put this to the theologian Rowan Williams.

[Rowan Williams]

Scientific breeding, the gradual elimination of inferior types and inferior races was just part of a liberating scientific project.

[Rory Stewart]

And it's striking that British politicians, bright British politicians, buy into this stuff.

[Rowan Williams]

They buy into it absolutely. And I think it's partly that when you raise the stakes and expect science to deliver to you absolutely clear and controllable patterns, there's a huge temptation, almost an investment in getting to those patterns rather quickly. And if those patterns then happen to be politically helpful, if they help to cement and reinforce aspects of your position, society or the world, well, whether you're conscious of it or not, those factors will be at work.

[Rory Stewart]

From the New Mexico desert come first pictures of a sequel to the atom bomb's final test. From this observation tower, scientists watch the result of their years of work.

The Trinity test at Los Alamos, New Mexico in 1945. Above ground nuclear testing in the United States continued throughout the 50s and 60s.

Miles into the air rises the giant shape of the now historic explosion.

Explosion Even without Armageddon, there has been an enormous cost to human life. J. Owens, author of the Modern World in a Trillion Particles, told me. How many people are thought to have died prematurely just because of nuclear testing?

[Expert on Nuclear Testing]

2.4 million is the claim from international physicians for the Prevention of Nuclear War. Including people who haven't even died yet. You know, it's been 60 years. But radioactive particles persist in the environment. Some of them have tens of thousands of years of decay time.

[Rory Stewart]

Cameramen and reporters put on canvas overshoes to guard against radioactive Particles. Tests reveal that harmful rays do not remain only the evidence of the terrible retribution so soon to follow.

[Expert on Nuclear Testing]

There's always that possibility that a particle from one of those explosions gets inside your body or touches your skin and goes ping. Just at the wrong time, which causes a mutation.

[Rory Stewart]

Presumably there were people saying, this is unbelievably dangerous. You're going to kill a couple of million people. And then presumably there were people on the other side saying, no, it's not that dangerous. Is that right?

[Expert on Nuclear Testing]

To an extent, though, I think I get the impression there was more patriotic support. You got a sort of pop culture builds around nuclear testing with parties in Las Vegas of people standing on hotel rooftops, cocktails in hand, watching the explosions. And it's only little people, really. Closer to the tests, people who are sheep farmers or Mormons living in Utah, or some of the indigenous Americans who had land around the test area in Nevada and Utah, where the prevailing winds went. They were seeing things on the ground. They were seeing their sheep with sores. They were seeing their sheep miscarry. They were, you know, actually close enough to just hear the sort of strange dust that might fall on their cabins in the days or weeks after a test. They could see that something was up. But that news did not manage to really filter out more widely.

[Rory Stewart]

And then there's the vast damage to the climate and biodiversity. There are so many of these examples. But one that has always struck me is from the American anthropologist James C. Scott. He looks at the fact that in the 19th century in Prussia and Germany, scientists who studied timber production decided that the most efficient thing would be to fell ancient forests and replace them with plantations of perfectly spaced, identical trees.

It was seeing the forest as essentially a natural factory for the production of lumber, and only that if you're just interested in the cubic feet of lumber and firewood that you can produce, then you want to go with the fastest growing tree, treating it like a crop and growing it in straight rows and of. They knew nothing about the environmental complexity of the forest ecosystem and destroyed two thirds of it. And the pests came. It's a way in which a single product is desired and everything else is organized without much knowledge of its importance and complexity. In order to achieve this single goal.

There's much more to be said here, which we can return to later in the series. But let's at least recognize first that knowledge can and has gone wrong, and not only in government. So far, we've concentrated on knowledge of human societies. And there perhaps it's most obvious that things can go wrong when we're trying to analyze humans knowledge in real science, however natural science we want to believe may be different. We see it as the purest and most reliable form of knowledge. But even here, many of our assumptions are wrong. For a start, the story we're often told in school is that knowledge grows as scientists slowly work their way through different phenomena in the world, coming up with new theories, testing them through experiments, and then ticking them off the lists as they solve them.

[Expert on Nuclear Testing]

Now I know and knowing is half the battle.

[Rory Stewart]

But in fact, great discoveries rarely happen like that at all.

[Ian McGilchrist]

Most of the great discoveries of mathematics and science were made by leaps of intuition and by insights of imagination.

[Rory Stewart]

The psychiatrist Ian McGilchrist, George Gaylord Simpson,

[Ian McGilchrist]

who's a very kind of center of the road figure, who part of the so called modern synthesis himself, said almost no great breakthroughs in science were made by the scientific method.

[Rory Stewart]

Often it is ignorance and imagination, not knowledge, which is at the heart of the scientific method and scientific progress. As the physicist Carlo Rovelli explains Copernicus

[Carlo Rovelli]

great discovery is that we are sitting on a spinning rock, that the Earth is rotating and going around the sun. To discover that is not very hard. If you are ready to question the obvious and acquired knowledge that we are sitting on an Earth that does not move. The hard point is not to discover something new, it's just to get out of the habit. That of course is like that. Of course the Earth does not move. It is always discovering that there is something we thought we knew and we don't.

[Rory Stewart]

And we don't begin to know quite as much about the universe as we imagine. The periodic tables on our classroom walls proclaim that we've mapped all the possible elements in the universe. But there is so much that we don't yet understand.

[Daniel Weitzen]

I would say we are staggeringly ignorant about the nature of the universe.

[Rory Stewart]

The physicist Daniel Weitzen we know a

[Daniel Weitzen]

lot about a very small fraction. We know how our bodies are made, the kind of matter we're made out of. But that only comprises like 5% of the stuff in the universe. There's another 25%. That's the invisible dark matter, intangible, unknown, but creating gravity that holds the universe together. And another 70% that's dark energy, which is accelerating the expansion of the universe. But it's something scientists are just beginning to grapple with.

[Rory Stewart]

This is true in biology as well as in physics. As the biologist Stuart Firestein points out,

we don't know how the brain works. That's a pretty big question. But we Also don't really know how one gene is turned on at one moment as opposed to another gene being turned on at that moment, one of which results in things going well in development, and the other results in some deformity or miscarriage completely or something to that effect.

[Daniel Weitzen]

We still do not understand what is space? How does time work? These foundational building blocks of the whole universe are complete puzzles to us. And when we open them up, eventually could reveal shocking surprises.

[Rory Stewart]

Dark matter and dark energy are called dark matter because we know nothing about them. But even those things which we know about in the universe we often don't fully understand. And the truths we have discovered can seem mystifying or even literally contradictory, even nonsensical, as the philosopher Rick Peales describes. A colleague of mine shared with me this experiment he conducted. So he had an elementary particle at one side of the Lake of Geneva, and he shot it to the other side without its ever having been in between. Those crazy things can happen at the level of quantum mechanics.

[Carlo Rovelli]

It's a history of my life as scientist Carlo Rovelli. I was going to school at university and listening to the lectures of relativity in the morning, the professor in quantum in the afternoon. And they were just giving me two totally different images of the world in the morning. The world is continuous. The space curves. Everything is deterministic. In the afternoon, space is flat, everything is discrete, is indeterministic. It's probability. You know, I was thinking, these two guys haven't talked to one another for decades. I mean, oh, they're idiots or what? It can't be. Okay? Great teachers, great professors, okay? And they were giving me a totally incoherent picture of the world.

[Rory Stewart]

Sometimes these contradictions can be resolved by using new metaphors or images to help us see things in new ways.

[Carlo Rovelli]

Think about historically, sunrise is what the sun moves up, right?

[Rory Stewart]

Yeah.

[Carlo Rovelli]

Okay. Then Copernicus comes and says, the sun doesn't do anything. It just stays there. So somebody could say, oh, my God, there is no sunrise anymore. No, there's still a sunrise just is not what we thought it was. Okay? There is still up and down. It's not that we thought it was. So here we are, readjusting our conceptual structure, becoming smarter, but we're not doing something different, I think, than when we are kids.

[Rory Stewart]

But in much of particle physics and astrophysics, we're still a long way from finding a satisfactory metaphor or language to make sense of what our equations suggest. We have to proceed without fully understanding Rowan Williams.

[Rowan Williams]

We create a sort of ecology of metaphor. This is a world in which we're going to need an awful lot of verbal resources to cope. And it seems to me that when we're up against that kind of question, what we say about the utterly mysterious and paradoxical distribution of energy in the universe. It's not so much that we're looking for a final map of the universe, the unified theory of everything that people dream of, so much as that we're looking for ways of finding language we can just about manage to sustain at a particular level in a particular area that doesn't make total nonsense, that allows us to. To take a next step forward in research and understanding.

[Rory Stewart]

We may never understand certain fundamental things about the universe, perhaps because of the limits of human minds and human contexts.

[Carlo Rovelli]

We are inside nature and we're looking from the inside with all the immense limitations of these little creatures looking around, sniffing around and getting a sense. If we view ourselves like that, then this narrative, this imagination of our perfect rationality, our perfect knowledge, getting to know everything, becomes a little bit meaningless.

[Rory Stewart]

The theoretical physicist Richard Feynman supposedly said, if you think you understand quantum mechanics, you don't understand quantum mechanics.

[Rowan Williams]

Physicists are becoming metaphysicists.

[Rory Stewart]

Daniel denicola and as they try to

[Rowan Williams]

reach into the difficulties of world that is not the world we can live in, they run against this perennial problem with science that it presumes the conscious observer, and we may not be the kind of conscious observer who can function on that level of understanding. It may be simply beyond us.

[M]

There's a lovely Buddhist story about this, and it's about a fish and a turtle.

[Rory Stewart]

The theologian Martin Palmer.

[M]

One day the fish says to the turtle, go out. Go out of the sea, go around, come back and tell me what it's like. So the turtle goes out and walks across hot sand and walks through grass and wades through a little stream, and he probably can't do this, but he climbs a tree, comes back into the sea, and the fish goes, okay, okay, okay. What's it like?

[Expert on Nuclear Testing]

What's it like?

[M]

What's it like? And the turtle goes, well, not wet sand. It's not like wet sand, okay? And not seaweed. It's nothing like seaweed. And the fish goes, no, no, no, don't tell me what it's not like. Tell me what it's like. And the turtle goes, I can't. You have no experience on which to build an image.

[Rowan Williams]

My great friend Douglas Adams wrote a sentence which I think is the finest thing he ever wrote.

[Rory Stewart]

TV producer John Lloyd, which is, there

[Rowan Williams]

is a theory that if anyone ever finds out why the universe is here and what it is for, it will instantly be replaced by something even more bizarre and inexplicable. There is a second theory that this has already happened.

[Rory Stewart]

It's easy to get the impression that science is revealing a world of clearly determined causes and effects and that there's nothing random about the universe anymore. You might even imagine, for example, that when you roll a dice, a real scientist would be able to predict exactly what number was going to fall by looking really carefully at the different causes and effects and the way that you release the dice from your hand. But that turns out not to be true.

It is in some ways predictable, or could be predictable, but it is so sensitive to the initial conditions or to conditions along the way.

Stuart FIRESTONE the temperature of the room

that you're in, the particular angle of your hand within microscopic degree, the drafts in the room, things that would just be too impossible to take into account completely. That it in fact is fundamentally unpredictable.

This idea that small initial differences can lead to vastly different outcomes is the core of chaos theory, the idea that a butterfly flapping its wings could trigger a storm.

You know, if the Earth had been seven minutes further along in its orbit 60 million years ago, that asteroid would not have hit it. The dinosaurs might still be here, and you and I would be cowering behind a tree as some little rodent.

But there's an even more radical idea that even with complete measurement, some things are inherently probabilistic or governed by chance rather than determined.

No, the universe is probabilistic all the way down. Now, that may sound very depressing, I would think. On the other hand, it's quite optimistic. If the world is totally deterministic, then what's the use? I mean, if it was all decided at the Big Bang, or the creation or whatever it is you want to believe was the first moment of the universe and everything was decided, and it's just following out a clockwork mechanism. Gee, life's not really that interesting, is it? But if it's really probabilistic, then we can play the odds. It's much better to play the odds than to try and fight an immutable law. Trust me.

[Rowan Williams]

It's something, isn't it? Which very paradoxically, science is teaching us all over again. Rowan Williams the science that we thought would deliver lots of absolutely crystal clear responses and strategies at its furthest edges and its most creative edges, in fact, reinforces for us this sense that we're a bit at a loss facing reality.

[Ian McGilchrist]

I think the idea of things being probabilistic is really important.

[Rory Stewart]

Ian McGilchrist My own view is that

[Ian McGilchrist]

all that exists, and very specifically life, exists at this edge between order and disorder, and there needs to be a degree of order and a degree of predictability. But that mustn't ever be total, because if it did, everything would be fixed, limited and fossilized. And the whole process seems to me one of creation. I mean, the least one can say about the cosmos is it appears to be creating all the time, and creativity is simply ruled out once everything is entirely fixed and predictable.

[Rory Stewart]

In this episode, I've begun to trace some of the ways in which we pretend to know human societies in the world and how often our models are deeply wrong, racist, self defeating, environmentally devastating, even potentially world ending. And we've also traced how limited our knowledge remains about the most fundamental aspects of matter and the universe, how our scientific model is often only probabilistic. We're encountering the importance of being careful with our claims of knowledge, of the use which we put knowledge to, and our assumptions about what we can understand. It's an argument about the stunning and often disturbing limits to our knowledge. We are often far more ignorant than we would like to acknowledge here. Ignorance is a lesson in humility. In the next episode, we begin to see ignorance as a source of creativity. You're just sort of filling in the blanks with your own imagination. How not knowing things can actually help. Artists, musicians, all creativity is a maintenance of childlike openness to experience. How ignorance in the form of innocence can be liberating. I get really, really, really inspired. The Long History of Ignorance is written and presented by me, Rory Stewart and produced by Dan Tierney. It is a BBC Audio north production for BBC Radio 4 and BBC Sounds.

[Ros Atkins]

From BBC Radio 4. This is communicating with me, Ros Atkins. This is the podcast where I talk to some of the best communicators like legendary magazine editor Tina Brown, the Olympic athlete and broadcaster Michael Johnson to find out why good communication really matters and how best to do it. Have you ever walked out of a meeting and thought, why didn't I make the impact that I'd intended to? Or perhaps you've put down the phone to the bank without getting the answer you wanted. We all have dozens of interactions every day and this series will provide you with practical advice for communicating effectively during them. Communicating with Ros Atkins Listen and subscribe on BBC Sales.

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