Freeman Dyson

At the age of four, he tried to calculate the number of atoms that constitute the Sun; at the age of five, he began working on a treatise on the development of nature; when he was eight, he wrote a sci-fi story about a trip to the Moon; he lost interest in biology after his first attempts to dissect crayfish; he entered the famous Winchester College, founded in the 14th Century, as a twelve-year-old and the only one who, in all the exams that lasted for three days—including Greek and Latin, not to mention algebra and geometry—received the top grades (a special higher mathematics teacher was assigned for him and his friend).
At the college he also—entirely on his own—acquired Russian: at the time, the best book on the theory of numbers, Ivan Vinogradov’s Introduction to the Theory of Numbers, was available only in Russian, so in order to better understand Vinogradov’s theory, he translated the book into English at the age of fifteen. A year later, together with a friend, he did a careful study of the three volumes of Whitehead and Russell’s Principia Mathematica, reaching the conclusion—independently of Kurt Gödel—that, in a mathematical sense, this impressive work leads to an impasse.
The next summer break Dyson spent alone, solving 700 problems from Piaggio’s Differential Equations and when, at the age of eighteen, he entered Cambridge, his knowledge of Russian helped him to establish a friendly relationship with Abram Besikovich, the only mathematician who took the liberty to point out to Wittgenstein the imperfections in his reasoning.
In order to keep his sanity at the British Operational Research Section (ORS) of the Royal Air Force’s Bomber Command during the Second World War, he did the first successful proofs in pure mathematics, which secured him a place at Trinity College (he lived below Wittgenstein, from whose rooms constantly wafted the smell of fried fish). Having discovered that there are many more uncertainties in theoretical physics than in pure mathematics, he turned to particle physics, under the Russian émigré Nicholas Kemmer.
One of the two teachers who recommended that he should move to Cornell University in the United States (after the war, it was the place where Hans Bethe had gathered some of the world’s best theoretical physicists) wrote in his letter of recommendation that Dyson was not “completely stupid” while the other commented that, at the age of 23, he was “the best mathematician in Great Britain”. Without having completed his doctoral thesis, Dyson became a professor of physics at Cornell University, where he befriended the brilliant physicist Richard Feynman, to whom he had a chance to explain the quantum field and whose “Feynman’s diagrams” he was the first to explain to a wider physicist audience as a specific theory in physics.
This time—he was 25 then—coincided with the development of quantum electrodynamics theory, for which all of its authors—Schwinger, Feynman and Tomonaga—with exception of Dyson, received the Nobel Prize in 1965 (the Prize is usually awarded to no more than three scientists at a time). It took some time for Robert Oppenheimer, the father of the atomic bomb, to recognize the approach by the young British mathematician and physicist as correct, but once he, had he appointed him a life member of The Institute for Advanced Study in Princeton, which had been home to Einstein, von Neumann and Gödel. At the age of 30, without a doctoral degree—“I despise the system of academic doctoral degrees in higher education”—he became a professor at the world’s most prestigious institute of exact sciences.
In 1958, Dyson was invited to act as the main consultant for Project Orion, a joint venture between private industry and the American government: he was to be responsible for physics in investigating the possibility of interplanetary space travel by nuclear pulse propulsion (about 2000 atomic bombs would be enough to make it to Mars; later Dyson confessed that his main interest in the project lay in the possibility of finding a reasonable way of getting rid of the produced nuclear weapons), yet in less than a year-and-a-half he had lost interest and returned to Princeton.
He admits that he finds himself incapable of being interested in anything for more than a year and is disgusted to belong to any kind of majority (defense of the minority position in science became his “profession” and it is no accident that one of the collections of essays addressed to the wider public is called The Scientist as Rebel, which illustrates his self-awareness as well as his understanding of scientific development). His later interests lie with the factors determining the stability of matter (the first interdisciplinary studies were done as early as the 1970s); the instruments that might help in establishing the existence of aliens unwilling to communicate with humans; the necessity for humanity to gradually colonize the Universe; and an original approach to the origins of life, which convinced everyone except the experts (his son George Dyson, a historian of science and technology, allows for the possibility that the theoretical analysis of the origins of life may be his father’s most important contribution to the history of science).
Dyson’s number, Dyson’s series and Dyson’s conjecture are well-known entities in pure math. Dyson’s sphere (a device that could use the Sun’s energy to meet the needs of humanity) and Dyson’s trees (this is a name given both to this idea to create, by means of genetic engineering, trees that would use carbon dioxide more intensively, and to similarly create biological organisms that could grow in outer space when a large part of humanity will have to move there), balance between science fiction and applied science. We also owe Dyson the algebraic formula for calculating the seam on a baseball (z = (p2/2)xy = (2 + √3)xy), which he produced in answer to a question from David Nelson, in 2001.
In the last decade Dyson has become one of the most authoritative voices to assert that “global warming” is first of all not global (it is limited to the cold regions, winter and nighttime); and second, there is no scientific evidence that it is dangerous, and third, that the related ideology and propaganda turns people’s attention away from much more pressing problems. Convinced that all misunderstanding between science and religion is caused by science attempting to be a religion and vice versa, Dyson has never concealed his religiosity and, in the year 2000, added the Templeton Prize (worth one million pounds sterling) for contribution to the progress of religion and science to his array of more than twenty honorary PhDs from different universities.
Indirect evidence that Freeman Dyson, even in his nineties, is still one of world’s most interesting scientists, is in his article published in May 2012, together with computer scientist and biologist William H. Press: they showed that contrary to the common assumption that the winning strategy in game theory’s famous prisoner’s dilemma is not to be too clever and/or too unfair, in the long term, cleverness and unfairness triumphs after all.

Arnis Rītups

P.S. I am grateful to George Dyson for his comments on this introduction.

I have to start somewhere, so how about we begin with some abstract questions? To what extent can science explain the world, and why should its explanations matter to us?

Good word, those are big questions! First of all, I take a very modest view of science. I think science is only a small part of our knowledge and shouldn’t be exaggerated. We have many other ways of knowing, which have nothing to do with science. In fact, for most of humanity’s history we got along very well without science. Science only started with the Greeks, roughly. Certainly, it has been a tremendous step forward but it is not the only source of knowledge. We have knowledge from history, we have knowledge from literature, knowledge from story-telling, knowledge just from practical experience—which has nothing to do with science. So to me science is just a set of tools which happens to be very effective in a certain domain.

But could you specify what contribution science has made? You said it was a significant step forward—you didn’t say it was a step backwards.

No, I would say it’s certainly a step forward! It’s a set of tools for studying the world in a very precise way. Having rather strict rules it is extremely helpful—it allows knowledge to be formalised. Of course, mathematics is one of the most useful tools. Mathematics is a big part of science that allows knowledge to be much more verifiable—you can measure things, you can verify them.

You said that the exactness of science is helpful.

Yes.

Helpful for what?

Well, for staying alive.

For staying alive?

I suppose I’m one of the lucky ones. I am 88 years old and still alive. Without science it would have been less likely to happen.

And you prefer being alive to being dead.

Yes, certainly.

What’s so good about being alive?

Well, it’s a matter of taste, of course. Some people don’t agree but those who don’t agree generally don’t do so well… Anyway, I would say that from a practical point of view the joy in life is something which most of us understand. It has nothing to do with science; it’s a value judgement—that life is precious.

So one good thing about science is it helps us stay alive longer?

Yes.

Is there anything else?

It has enabled us to travel around and see much more. There’s a lot more freedom in fact. Before we had science, essentially all societies had slaves. That was necessary—you had to have slaves if you wanted to be rich. Now we can be rich without having slaves. I think that’s a big step forward.

Have you ever understood the attraction of scientism?

Yes! Some of my friends are people who are personally quite reasonable but they have this exaggerated view of science—they think that science can explain everything. So it becomes a kind of religion. They believe in science as a guide to everything and, to my mind, this is claiming much too much. There are many very deep questions that science cannot answer.

Could you explain why your friends and colleagues have been attracted to the idea that science can explain everything—everything that matters?

I suppose it is a natural tendency in humans—to try to simplify. Often it is useful—to make the world as simple as possible so that it is less confusing and you can have an easier time making judgements. It’s always attractive to have a set of dogmas which you believe and which answer all the questions. Sometimes this has the form of religion and sometimes the form of scientism—believing that science can be the answer to all questions. I think this is not altogether different. Marxism was in a way the same kind of thing—it was also a mixture of science and religion, taking the worst features of both.

You mentioned that on a personal level these people are pretty reasonable. Nevertheless, they fall into the trap of scientism. Does this mean they’re insensitive to the deep, important questions science cannot solve?

I think some of each. My friend, E.O. Wilson, whom I consider very reasonable…

…a specialist in ants…

Yes. He wrote a book called Consilience, which actually makes a case for scientism. ‘Consilience’ means when all kinds of knowledge come together and become then a part of science. He is himself a very sensitive and, I would say, honourable person. I like him very much. Whereas, on the contrary, there’s Richard Dawkins who is famous, of course, for believing very strongly in science and disbelieving everything else. I would say he is an unsympathetic character, but that’s only my prejudice.

You mentioned ‘deep, important questions’ which science cannot answer. Could you give me a couple of examples so we have something to start with?

I suppose these are mostly questions of ethics and morality: the difference between good and evil, why some things are considered good and others… evil. Those are, I suppose, the deepest questions. But there are more: whether you believe in ghosts, whether you believe in spiritual forces, in the existence of a human soul… That is certainly not a scientific question but to many people it’s very important.

But plenty of scientists seem to think that these are just old phenomena, which are now investigated by science. ‘The soul’ as something unavailable to science is a very strange notion, isn’t it?

Well, it’s certainly something which I would say most people believe in, in some fashion.

Do you believe in it?

Yes.

What is the content of this belief?

Well, I suppose it’s just a question of in­tro­­­­­s­pect­ion, of looking inside—when one is aware of oneself. It sort of goes deeper than language—we can’t really describe what it is we feel but we feel it all the same. There’s something there which we call ‘I’, the agent. We don’t understand how it works and science is probably not very helpful.

But do you exclude the possibility that it’s just an illusion, that this self-introspection is just an illusion?

Well, of course… I’m always quite happy to be wrong. Everything I say, of course, may be wrong—that’s clear. I don’t claim to be the Pope.

Where’s the happiness in being wrong?

I think it’s much more interesting to be wrong and to be contradicted than to just… not have opinions at all.

I recall you stating in one of your articles that science is about things and theology is about words, to which Huston Smith responded that this can’t be true because God is the thing, etc. Do you still believe science is about things and theology is about words?

Yes. But I do make a distinction between theology on the one hand and religion on the other. I think religion is mostly not about words—religion is a way of life. Of course, it involves words—in any religion there’s literature attached, which is important. So it’s partly about words. But theology seems to be only about words. I would say I am a religious person but I have no interest in theology.

When I asked you about the deep, important questions which cannot be answered by science you only mentioned a distinction between good and evil. Does this mean that questions such as the origins of everything, the emergence of life or the emergence of consciousness are realms belonging to science?

Perhaps. We don’t know. The origins of life could be a scientific question. We haven’t reached it yet. But certainly, one can talk about it in a scientific language. We don’t have the tools yet for actually investigating it.

Could you explain to a layman how it all began?

This is again, I think, probably not a scientific question. Science explains what happens but it doesn’t explain why it happens.

But still, science could explain how it happened, how everything began?

It might. I don’t think it has come close to it at all yet.

But what is the closest approximation? Suppose a 5-year-old child asked: How did it all begin? What would be your explanation?

I would say that we simply don’t know. At the moment we have made a great deal of progress in exploring the past and finding out what happened when. That has been remarkably successful. But that doesn’t tell you why it started or how it started.

From which moment in the past does our knowledge start to acquire any shape? We don’t know about the very origins, the ultimate beginning, but there is apparently some stage at which our knowledge is more or less formulated?

Yes, and I think it’s remarkable how early it is.

One second or one minute after the beginning?

Well, maybe even less. I mean, we have at least a mathematical description of what we call ‘the inflation’, which is the time when the universe was very small and compact. And then it grew extremely fast—in a small fraction of a second.

That we do know?

No, we don’t—that’s a mathematical model, which may or may not have something to do with reality. So I suppose our first real knowledge of what really did happen is roughly one minute after, as you say. I think Weinberg’s book, The First Three Minutes, makes a good description of that. As soon as we have nuclear processes of hydrogen converting into helium—and nuclear processes begin at about one second—from that time on we have verifiable facts. We can measure how much helium there is in the universe, check it against Weinberg’s model and see whether it agrees. That is beginning to become scientific.

Still, mathematical modelling plays a large role. I take the ancient view seriously—that mathematics is deeply interwoven with imagination. And insofar as mathematics is involved with imagination there is no way of understanding how far the model corresponds to whatever is out there. Or am I wrong?

I think we have a lot of evidence that the models are good.

And there is enough evidence for us to trust those models?

Some of them. I mean, there are many which I don’t trust. (Laughs.) Climate models are particularly bad.

The ones describing climate change on Earth?

Yes. They don’t even begin to describe the real world—they’re much, much too simple. But when you go back to the beginning of the universe, in fact things become simpler. So mathematical models are actually better when you’re talking about early universe than when you’re talking about today. With time, the world has gotten more complicated.

One of the most puzzling notions I have encountered in the descriptions of the universe is dark matter, dark energy. I don’t know the exact numbers and I’m not sure anyone does, but if about 70% of the stuff out there is completely unknown, what is the value of any descriptive model?

Well, the models still include that 70%. And the beauty of the models is, of course, that you don’t include all the details of the real world. In this case, since we don’t know the details, it makes the models look better.

Do you understand dark matter’s function in the whole system?

No! Of course not.

But to what extent can we even name it? It seems that dark matter is just a name for X. Or is there actual matter there?

We don’t know what it is but we know what it does.

Please tell me a couple of things it does!

It streams around, rather like visible matter. What we have learned just in the last few years is that dark matter, in a way, is very similar to visible matter—it’s mostly concentrated in the same places where you have a lot of galaxies, which are bright. So there is a strong correlation between dark matter and visible matter, which is not so surprising since they attract each other. So we know in a fair amount of detail where dark matter is. But that’s about all we know.

We know the location.

Yes, and we know roughly how it’s flowing. That’s already quite a lot. It’s much more than we knew ten years ago.

Do you suspect there might be something hiding in the dark matter?

Of course! But that makes it interesting. Science is all about things we don’t know.

You mean it’s not about the things we already know?

The interesting part of science is the part we don’t know.

Could you list five of, to your mind, the most important things we don’t know?

Well, certainly dark matter is one. Then, of course, there’s the whole of biology—we hardly understand anything about biology. One of the big questions which I am arguing about with biologists is whether evolution is mostly driven by individual selection or mostly driven by group selection. And that is a very controversial question. Mr Dawkins is again very dogmatic—he says everything is individual selection. Ed Wilson says, on the contrary, that group selection is at least as important. I agree with Wilson, I think group selection is actually more important for big steps in evolution. When all species are wiped out it’s a group that has failed, not just the individual. But anyway, that’s question number two—how evolution is driven. Number three is, of course, the origin of life—that’s still a total mystery. What else is there? Almost everywhere you look there are mysteries. Certainly, how the human brain works—whether human memory is actually an analogue or digital system, which we don’t know. That’s four. Then there are more practical questions, which I am also interested in—whether natural oil and gas are in fact biological or whether they are coming up from deep in the Earth and have nothing to do with biology.

I thought that had been settled long ago—that they’re fossil remains.

No, that’s the prevailing dogma here [in the US] but actually in Russia they believe the opposite. I agree with the Russians on this.

Really?!

Yes.

So you think that oil might come from deeper levels of the Earth?

Much deeper, yes. If you look at the universe as a whole, hydrocarbons are the commonest chemicals—everywhere you look hydrogen and carbon are the two dominating elements. Almost everywhere you find that hydrocarbons are abundant. And probably that’s true on Earth as well. Probably the inside of the Earth is saturated with hydrocarbons. When the Earth first formed they were there and they are still there. Sometimes they leak upward because they’re buoyant and lighter than rocks—they come up and make oil fields and gas fields, which we discover. So that’s certainly a possibility, and many people believe it. In this country for some reason the biological view became popular.

Do you think we can reasonably describe the whole universe as randomly made, as resulting from a chain reaction of accidental events? Or is there some inner logic, some rationality—however vague the term—within the processes? Or is it just randomness?

Well, it’s a combination of both, of course. There is a very large element of randomness. Randomness is what produces all the beauty in the world. The fact that things are always differentiating—becoming more and more different as time goes on so you get more structure and more and more elaborate patterns in the world—is largely the result of random processes. But the fact that this is possible is, of course, governed by laws which are not random at all. The laws of nature are fixed and invariable—that’s something we have learned. The laws of nature make this randomness prevail, and that’s due to a very interesting property of gravitation. When you have any object that is held together by gravitation it has negative specific heat. This is a fact that most people are not aware of.

I am not sure I understand what negative specific heat is.

Negative specific heat means that if you pump energy into an object, it becomes cooler. It’s just the opposite of what you would expect. As you supply more and more energy it gets colder and colder. And if you take energy away it gets hotter.

What scale of events are we talking about?

This is true of something particularly on the astronomical scale. It’s on the astronomical scale that gravity becomes important. The sun is a good example—as the sun constantly shines away energy, it gets hotter. And that’s true of stars; it’s also true of almost all large objects.

By emitting energy they become hotter?

Yes. Since heat always flows from a hot place to a cold place—that’s a natural way heat always flows—it makes the differences larger. So when you conduct heat or radiate heat from one place to another it means the source of energy becomes hotter and the sink of energy becomes colder. So the differences become larger as time goes on.

This is one of the laws of nature which determine the randomness as it grows?

Yes. It implies that you always have larger and larger differences between one region and another. An example is the sun and the Earth. The sun is hot, the Earth is cool and the energy, of course, is going from the sun to the Earth and making the sun hotter and the Earth cooler. So the Earth is a good place for life to develop.

Is there something on which the laws of nature stand, on which they’re based? Or are they somehow causa sui, independent of anything?

Well, of course, we don’t know. What we know at the moment is that the laws are still very complicated. Probably we haven’t come close to the bottom, whatever the bottom is.

Maybe there are elephants all the way down?

Yes. Or turtles.

Does the notion that the world was created make any sense to you?

Yes.

How does it make sense?

I see that there is a thing called mind…

In the universe?

Yes. We see it operating in ourselves.

How do we see it operating?

Well… just that we are aware of the fact that we have minds and we think, as in Descartes’ remark: Cogito ergo sum.

By analogy, do you think the universe itself has a mind?

Very likely. There certainly are mental processes on some scale and no reason why they shouldn’t exist on a larger scale. We know that on the smallest scale—on the quantum mechanics scale—there is free will. If you take an atom, you see it’s strictly unpredictable. That’s what quantum mechanics is all about. Every atom has a probabilistic behaviour, which means it’s free to do what it likes.

Isn’t it strange that the Epicurean Lucretius was already talking about something similar?

Certainly. I never read Epicurus but, yes, the ancient Greeks were amazing people. They had a lot of wrong ideas but also some very good ideas.

The clinamen, or the unpredictable atomic twists an atom can make, was apparently an idea put forward by Epicurus—without any experimental basis!

And now we have the experiments to prove it. So the atom in a sense has a mind of its own—on a very rudimentary scale.

So you assume that the universe might have an analogous mind of its own?

Yes.

A modern prejudice is the idea that the mind is entirely dependent on the brain. What alternative way of thinking about the mind would allow you to conceive of the universe having a mind?

I don’t think about it much… it’s quite a mystery. What is certainly true is that the universe somehow seems to have this… what I like to call principle of maximum diversity. Somehow the universe has a tendency to be as interesting as possible. As time goes on it becomes more and more diverse, more and more interesting. That seems to be somehow built into it, and I don’t see any of the laws of nature which make that happen. So I would say that creativity is somehow built into it.

But despite this tendency to make itself as interesting as possible, some 70% of the stuff is still dark.

Yes.

And that doesn’t seem very diverse.

Well, we don’t know! What happens when we discover something new is that we always make a simple model of it. We don’t yet understand it so we make a simple model, which makes it look simple. You can’t help doing that. If you discover a new planet you think of it as something just like the others we have. But when you look at it in detail you find it’s quite different. And that I think will probably be true of dark matter. At the moment we think it’s simple just because we don’t know what it’s made of. Once we’ve found out what it’s made of it’ll probably turn out to be just as complicated as we are. We don’t know.

What I find strange about your idea that the universe is trying to be as interesting as possible is the kind of aesthetic wish you ascribe to the universe itself.

Yes! No, it is quite paradoxical.

But you believe the mind of the universe might have some aesthetic tendencies?

That’s the way it looks.

Einstein said the only God he finds acceptable is Spinoza’s God. Is this compatible with your own understanding and beliefs?

Yes, I think it is, except, of course that Einstein did not accept quantum mechanics. I think he was clearly wrong. To me quantum mechanics is a very, very big part of this, but for him it wasn’t necessary. His Spinoza’s God was in a way a very boring concept compared with mine.

We’ve touched upon the largest scale possible. Now let’s consider the smallest scale possible… I remember being in secondary school and drawing the structure of an atom, which looked like a tiny planetary system. I was somehow suspicious of that picture and still am because it seemed to be based on something people had seen when it was describing something they hadn’t seen. How justified am I in suspecting that that picture is just for kids, so to speak?
Certainly it was helpful at the beginning, before you had quantum mechanics. With quantum mechanics, of course, it’s totally different. The atom is something active—almost alive you might say. The atom is something very dynamic. So that picture misses the main point.

Which is?

That the atom has freedom of movement and freedom to decide how it will behave. It doesn’t have a fixed shape.

Isn’t that a kind of anthropomorphisation?

Yes. Definitely.

And why are you doing it?

I would say it goes the other way.

We are atomistic rather than atoms anthropomorphic.

I think of the human brain as a sort of amplifier which takes the mental processes of atoms and amplifies them to produce organised behaviour. That’s what brains are for essentially—to use the freedom of atoms so that we have some sort of free will ourselves.

They use atoms to produce thoughts?

Yes.

Sorry for the overly simple nature of this question, but what stuff are thoughts made of?

I have no idea. I would just say that mind is something we don’t understand at all. I mean, certainly not as something made out of atoms.

You said atoms come in all kinds of shapes, that their shape is not fixed. Does this mean that we humans have seen atoms?

Yes.

We have?

Oh, yes. I once saw one that had a name—she was called Isabelle. It was actually a barium atom. It was a trick. You can make an atom visible if you hold it in a vacuum with magnetic field and then shine laser light onto it.

So you did see an atom?

Yes. Shining like a little star. It was there for about a week.

And how often did you look at it?

Oh, I was just visiting for an afternoon but it was there all the time. The fellow who made that discovery—at the time he was in Seattle where he had his lab—was one of these scientists who is really more of an artist than a scientist. He had a wonderful gift for designing experiments. Then he moved to Harvard, and now he’s a professor there.

Who called the atom Isabelle?

He did. Just for fun.

Is it one of the few atoms humans have seen?

Yes. For it to happen, it has to be carefully arranged.

And what shape did Isabelle have?

It was far too small for me to see, of course. It just looked like a point of light. Of course I could see her only because she was moving back and forth very fast, being bombarded by the laser.

Was she trying to avoid the laser?

No, she was just absorbing and radiating away the light.

Now again the 5-year-old kid asks: Can you describe the structure of Isabelle or her siblings?

She has a big nucleus which is positively charged and a lot of electrons, which are moving around in clouds—not really in orbits but in clouds. These clouds move as the laser light comes in and kicks them around. So they scatter the light and we can see the result of the scattering. It looks as though we’re seeing the atom but it’s really not so much seeing the atom as it is seeing the scattered light.

People have assumed that there are other things inside the nucleus. To what extent do these tiny bits make sense and at what point do they become pure human imagination?

I think you can’t really make a sharp separation there. When you talk about the little pieces inside the nucleus, these are of course mathematical models… they can never exist independently. You can’t isolate them—they only exist inside the nucleus. So you might say these are real things or you might say they are just mathematical models. They are somewhere in between—they have some of the properties of real things but they aren’t ‘things’ in the ordinary sense because you can’t isolate them.

Then we come back to the level of atoms. What role do atoms play in the universe? Are they building blocks or something else?

They are, yes.

Is it a sufficiently comprehensive description of their role, that they are the building blocks of the stuff the universe is made of?

Yes, one of the building blocks. The fact is there are only a few building blocks, which is a striking fact—that only a limited number of kinds of atoms… Then there are other building blocks, like light waves, gravitational waves, nuclear forces… That only a small number of building blocks exist is one of the things we have learned.

Is it correct to describe an atom as some sort of stuff? Or is it still a kind of configuration of energy?

It’s both. I would say it becomes stuff when you have a lot of atoms together.

But at the atomic level there is still nothing we could describe as life.

No.

Can you tell me at what level the possibility of life emerges?

Biology begins when you have probably about a million atoms; for example, in some viruses. So it is a collective thing—life belongs to a big collection of atoms, when they become organised in a strange way which we don’t understand. I mean, we absolutely don’t understand how our cell actually works. That, of course, was the big mistake made by Francis Crick and James D. Watson when they discovered the structure of DNA.

What was their mistake?

They said, “We have understood the secret of life.”

But they hadn’t?

No.

And why did they think that they had?

Because they had understood replication! Replication is one molecule replicating itself, making a copy of itself. And that was something they had understood, which was wonderful! It’s a big part of life but it’s not by any means the whole secret. Replication is, in fact, the easy part. The difficult part is what we call metabolism.

Stoffwechsel?

Exactly, Stoffwechsel. That’s exactly right. And that’s what life really does most of the time. That we don’t understand.

But do we understand why those combinations of atoms occurred in the first place?

No. What we do know is that atoms which are important for life are also the ones that are abundant in the universe.

They are the common elements: hydrogen, carbo-hydrogen, oxygen, sulphur. These are all elements that are quite abundant everywhere. So it was natural they would be used when you start to organise life—the material happened to be there. So that much we can understand. We understand the tiny bit about the chemistry— that these atoms have a tendency to combine. Carbon is particularly good at combining with itself and making long chains so it’s natural that life would make use of that. That’s about as far as it goes. We don’t understand how you go from a random mixture of molecules to a living cell.

In some of your talks you’ve mentioned the possibility that completely different kinds of life than the ones we know might exist in the universe.

Yes.

On what do you base such an assumption? And can you describe how different these life forms might be?

The simplest way to imagine another kind of life is just to have it in a computer. You can simulate evolution in a computer. That is what Barricelli was doing here in Princeton. He was a strange character. He was Norwegian but had an Italian mother or father, so he grew up in Norway with this Italian name. He came to Princeton at the very earliest time when the first computer was built here and he did simulations of living creatures on a computer. It was amazing how much he did! With that tiny memory… By contemporary standards that computer was amazingly primitive. But he actually saw these creatures evolve! They developed parasites, they evolved into new species. These were just completely artificial organisms—they were only made of zeros and ones. Nowadays, of course, people do the same kind of thing but simulating life in a more realistic way.

Are there any interesting results?

Well, sometimes something useful comes out of this… . They used this trick for evolving drugs, for example. But it’s not really what you have in mind. I mean, this is a very artificial kind of model for life. It’s not life. The more interesting question you were raising is whether other kinds of life might exist in the real universe. That, of course, we know nothing about. We haven’t the imagination to design some other kind of life. But certainly, it could exist.

There is no objective reason to exclude it, you mean?

Right.

A few years ago a big fuss was made about a couple of scientists who had finally created—synthesised—life.

Craig Venter.

Yes. But apparently this wasn’t exactly what they did. Since you’re saying we don’t know some very basic things about how life emerges, this sort of precludes our being able to synthesise it. But could you comment on that event?

Oh yes. Venter—I happen to know him well. He is an excellent scientist, only he also exaggerates what he is doing. What he did was synthesise the genome and the genome, of course, is the part of the cell that replicates. He made that completely artificially so he has the complete genome for a new creature. But then he makes the same mistake that Watson and Crick made—he thinks that’s all there is! And, of course, in order to have a living creature you’d have to take the genome and put it into a cell so it can actually function. He doesn’t synthesise the cell—he takes the cell already alive and puts a new genome into it. That’s what he actually does. So it is a new genome, but it’s not a new form of life.

But as far as I understand, attempts have been made to make artificial cells?

He calls it an artificial cell but it’s not really. It’s an old-fashioned cell with a new genome in it.

Do you think it is generally possible to synthesise life?

If we understood how the cell works, yes. We don’t know yet. So all we can do is take an actual cell… nature provides the cell, and then we play around with the genome.

Should I understand your description of atoms being alive as a sort of metaphor?

Yes.

Aristotle suggested that it’s the principle of self-change which makes living things differ from non-living things. Has our understanding of what distinguishes living things from non-living things advanced, on this very general level?

No. I would say not at all. But then, of course, there’s been a huge advance on the level of details.

But conceptually we are still in the same boat as Aristotle?

Yes.

Then could you evaluate the idea—the so-called Gaia hypothesis—that the whole Earth functions as a kind of unitary system, that it has enough inner unity to be described, in a sense, as alive?

I think that there are two quite separate ideas, which go under the same name of Gaia—I would call them the ‘weak Gaia’ and the ‘strong Gaia’. The ‘weak Gaia’ simply says that the Earth is a very closely coupled system in which the whole system works together to maintain itself. That’s a very weak statement but it’s certainly true. The strong statement is that Gaia can think ahead and knows how to arrange things in order to survive. That’s a sort of religious form of Gaia, as essentially a goddess who takes care of the planet. I would say that the strong version of Gaia is a religion and it has nothing to do with science.

A somewhat related view has emerged concerning humans as viruses—as a sort of infection of the universe, which has appeared by some error, and now Gaia or the universe is hoping to get rid of us. How much sense do you make of the idea that humans are a virus?

Of course, it’s true in a sense. There was a wonderful American poet, Robinson Jeffers, who expressed this beautifully long ago, “One day the Earth will wake up and shake off humanity.” So it’s quite an old idea. And there’s a lot of truth to it, of course. But I would say it’s poetry and not science.

Which part is true?

That humans are, in fact, taking over the planet and destroying a lot of the creatures that existed here and destroying a lot of its beauty too. In a very real sense we are parasites. So that’s all true. What’s also true, of course, is that other species have done the same thing. Not on quite such a big scale, but … that’s the way nature works.

Which other species?

Well, in particular disease germs. Insects are particularly good at this… funguses… every disease is just a successful parasite. So we are only one kind of disease. (Laughs.) We have the advantage of very often being aware of the damage we are doing and very often, in fact, being able to make things better. I always think of rabbits in England, which were the result of human actions. There were no rabbits in England until about, I think, a thousand years ago. Then some clever person brought in rabbits from somewhere and, of course, they transformed the whole landscape—they ate up a lot of the plants. In fact it made the country much more beautiful. So I mean humans were already changing the landscape long ago, sometimes improving it and sometimes making it worse.

On several occasions you’ve suggested that humans might start using interplanetary real estate—inhabit other planets. How likely is such an option, since we might destroy ourselves before it becomes possible…?

Well, it’s always possible but I think it’s very hard for us humans to destroy ourselves. It’s not as easy as people imagine.

How come?

Well, because we are extraordinarily resilient.

Like rats, you mean?

Yes. Probably rats and humans are about equally good. (Laughs.) It is remarkable—we are a species which has specialised in being resilient: moving from one climate to another and being able to adapt, learning how to keep warm in cold places and keep cool in hot places… My daughter has a house in California. She’s a veterinarian so she has a house full of animals. She rescues animals. So she has about, I think, twenty-two animals in the house, of different species. We were staying there one weekend and it was extraordinarily hot. It was around 50°C, which is unusual even there. And at the same time the air conditioning was broken. And it was a weekend so we couldn’t get anything repaired. So we were sitting in the house, simply roasting in this high temperature. And it turned out that we were the species which actually suffered least. Even the rats were having a worse time than we were. Our daughter had to take the rats and put them in the animal hospital so they could keep cool. The animal hospital had air conditioning…

But we were able to survive quite well!

Well, that gives us some basis for optimism about the future.

Yes! When you look at the possible ways we can destroy ourselves you’d think nuclear war would be the most likely to wipe us out. But if you look at a real nuclear war… Of course, it would destroy all the cities, which would be sad for all sorts of people—there’s no doubt it would be a huge disaster—but there would still be a lot of villages left where people would hardly notice. There would be places that happened to not get radiated. When you have a lot of radiation in the air it mostly comes to the ground via rains. So if you happen to be in a place where it’s not raining, you’re lucky. Also if you happen to live in a cave, even a few feet underground, it reduces the radiation very strongly. So it’s very hard to imagine there wouldn’t be lots of humans surviving. And, of course, it takes only a few to start the species all over again.

We have touched upon two moments in the big picture that remain unexplained: the origins of the universe and the emergence of life—as you said, a lot is still unclear. Let’s discuss another—the emergence of some form of consciousness in a living being. Is there any sense in describing the biological system as teleologically oriented towards an increasingly likely appearance of consciousness? Or is such a teleological picture out of the question?

I would say it’s quite likely. The principle of being as interesting as possible is, of course, just a part of this teleological picture. It’s a general statement of the same thing—that to be as interesting as possible the universe must be conscious of itself. It’s part of the same process. So I don’t know whether or not it’s somehow written into the structure of the universe from the start, but it does seem to be some sort of miracle we don’t understand.

So you do not exclude the possibility of teleological, goal-oriented processes in the universe?

No.

Do you understand why throughout the centuries there’s been a lot of prejudice against all sorts of teleological explanations?

I would say that prejudice is quite justified since most of the claims for teleology turned out to be wrong. Having a teleological explanation makes it much too easy to explain things. Most of the time it turns out to be an illusion. But it may still be true in the large. I wouldn’t say I believe it, but I think it’s a possibility.

It’s a strange fact of human life that thinking about one’s death somehow intensifies one’s life. Do you have an explanation for this close relationship between consciousness and death?

No, I don’t think I would say I have an explanation. It’s certainly common sense that if life went on forever it would be very boring. (Laughs.) It would be very boring to have to go through the same routines over and over forever. I think it’s a practical matter. Certainly, human society absolutely depends on people dying. If everybody were still around, there would be nothing much for the young people to do. (Laughs.)

Have you ever found a use for philosophy in your scientific thinking?

I think the answer is no. When I was a student I studied philosophy. I read quite a lot of philosophy—I took it seriously. But it never turned out to be useful. I don’t think that was just the result of prejudice. I think, in point of fact, there are two kinds of scientists: those who think philosophically and those who do not. I am certainly the kind that doesn’t.

What will happen to your soul at the time of your death?

Of course, I don’t know. I know my mother had a way of looking at that—she said she would just build back into the world soul she’d come from. She would go back with her wisdom and still contribute something to the world soul. I think that was a very nice view—it’s a sort of poetic way of looking at it. I wouldn’t say I believe it, but I would say that’s the closest I come to the view of what might happen. But whatever it will be is probably totally different from what we imagine.

What might be the most interesting scientific discoveries in the next decade?

That’s a question you cannot possibly answer because by definition the really interesting discovery has to be a surprise! If you only discover something you expected then it’s not interesting… I think the Higgs particle is a very good example of this. People make such a fuss about the Higgs particle but in fact it would have been much more interesting if we had not been expecting it. So the answer to your question is that we can’t possibly think ahead. All the really important discoveries are completely unexpected.

Do you need a genius to make a discovery?

Not always. You need a new tool. And sometimes a genius. There are two kinds of discoveries: those that come from new ideas and those that come from new tools. For a new idea you need a genius but for a new tool you don’t.
Then maybe you could mention a couple of recent ideas that might potentially lead us to new discoveries?—Recent ideas, not tools.

I think the most interesting discovery in the last ten years—that’s the question I can answer much better—was the thing called human accelerated regions. A fellow called David Haussler from California discovered this. And these are just two little places in the genome which he discovered.

Related to the hand and…

…the brain, yes. These are regions which are identical in six different species. What he did was simply compare genomes from different species. He went to chickens, dogs, cats, mice and rats, chimpanzees and humans—seven species. These regions are identical all the way from chickens to chimpanzees—this means they haven’t changed for three hundred million years or so in common ancestors of birds and mammals until today, so they must be doing something very essential. They’re different in humans. In humans they’ve had 18 mutations just in the last five million years, since the common ancestor of humans and chimpanzees. So this implies that these little pieces of DNA are doing something quite essential which makes us different from the apes. And as you said, one of them happens to be active in the cortex of the brain and the other in the hand, which is exactly what you would expect. They are also very active just in the period when the embryo is becoming organised, halfway through the embryonic life. They are not genes—they do not code for anything—they are just a part of the genome. We don’t know what they are doing.
Does this discovery also suggest a hypothesis about why these pieces of DNA emerged or where they emerged from?
No. I think what’s important about this is that it’s a new tool, a new way of looking at how the genome is organised. The fact is these pieces of DNA, which have nothing to do with genes, happen to be an apparently essential part of the story. So it looks like a new tool for understanding the genome. And also a new tool for understanding human nature—that’s why I find it important.

Beautiful! Thank you very much.

You’re welcome. I am exhausted so it’s just as well we’ve come to an end. You squeezed the orange dry…

I really appreciate your granting us so much of your time.

I enjoyed this too! It is always very interesting to talk about… speculative questions.

Questions by Arnis Rītups