George Ellis
Cosmologist
‘I think there’s a moral reality. I believe passionately that apartheid was an evil. I believe that the Holocaust was an evil. I think that’s a fact, a moral fact.’
FULL INTERVIEW 47 min
‘You can ask how different can the laws of physics be and still enable life to exist. And it turns out there are a great many ways in which, if you vary physics, pretty soon life cannot exist.’
TranscriptArd: Could you explain to us the concept of fine-tuning in cosmology?
GE: Okay. Well as a cosmologist one imagines imaginary universes, counter-factuals, and tries to see if you can learn anything. And if you imagine other universes, not only will they be bigger or smaller, expanding faster or slower and so on, but they can have different laws of physics. Because one of the things as a cosmologist one wonders about is, why are the laws of physics as they are?
So if you imagine the other laws of physics, you can ask how different can the laws of physics be and still enable life to exist. And it turns out there are a great many ways in which if you vary physics, pretty soon life cannot exist. And so there’s what’s called fine-tuning, namely that physics has to lie in a very restricted range in order that we, living beings, can come into existence. And it focusses, in particular, on something called the fine-structure constant, which is basically the strength of the electro-magnetic force, and the cosmological constant, which is how fast the universe is accelerating at the present time. And in either case you can show if they lie outside of a rather restricted range, in the one case, atoms won’t exist and therefore we won’t exist, and in the other case galaxies, and therefore planets won’t exist, and therefore we won’t exist.
David: I once heard you talk about Fred Hoyle in this. Could you tell me that story?
GE: The famous story about Fred Hoyle is he was one of the early people trying to work out how the elements out of which we are made come into existence, and he was particularly concerned about carbon.
In order that carbon exists, there has to be this excited state in the carbon atom. Now it turns out that the existence of that state depends on the fine-structure constant, and so there’s a link from the fine-structure constant through to this excited state, through to the fact that carbon is created in stars and thereby enables us to come into existence.
So if you imagine universes scattered around with all sorts of values of these constants, almost none of them will allow life: you have to lie in this very narrow band.
David: And how do you account for that then?
GE: How do you account for it? Okay, there are popular and unpopular versions. You can do it in three ways. One is to say it’s just chance: the universe just happens. Now, by chance I don’t mean it’s probable: it’s not probable or improbable, it’s just the way it happened. Now that’s a philosophically impeccable solution, but people don’t like it because it doesn’t get you anywhere.
David: It’s not much of an explanation is it?
GE: It’s philosophically impregnable.
David: Okay.
Ard: You say it just happened, and that’s it. If it didn’t happen then we wouldn’t be around.
GE: The second one is to try to say it’s probable. Now how do you try to say it’s probable? Your problem is there’s only one universe with one value. So if you can imagine an ensemble of universes which actually exist, they don’t exist in your mind but they physically exist, in some of them life will be able to come into existence.
David: Is that what people call the multiverse?
GE: That’s the multiverse and this is the scientifically preferred version of Martin Rees, Steven Weinberg. A lot of people prefer this.
Ard: So there would be just many, many universes?
GE: Yes.
Ard: So most of those universes would not have life, but if you have enough of them, eventually one of them will have life.
GE: I have a problem with this because if there is that multiverse out there, the question is, can you prove it exists? And in my view you basically can’t. So I think this is a philosophical but not a scientific solution to the problem.
Ard: So if you had the multiverse, if you had many different universes, enough universes that one of them would have life, do you think that would still need some kind of fine-tuning?
GE: Yes, because the problem just recurs at the next level. I can construct you a multiverse in which none of the universes exist. The multiverse, if it’s going to be sensible, has to have laws which create the multiverse. That’s going to have constants of nature in them, and some of those constants will allow the multiverse to allow it.
David: Otherwise you get the wrong multiverse?
GE: Yes, and so then, if you follow this up, you get multiverses of multiverses of multiverses.
David: As you say, it’s not getting you anywhere. You’re just pushing the problem back.
GE: Philosophically it doesn’t solve a thing, it just pushes you one step back. And then, of course, the final one is that the reason that the constants are what they are is that something, or some purpose, or some principle, or something, intended life to exist, which of course relates to the religious world view in some sense. It’s very unpopular in scientific terms, but again, philosophically, this is a perfectly viable position.
Ard: So you’re saying basically that the three possibilities are: happenstance, it just happens, just blind luck; or some kind of multiverse, or maybe some kind of providence?
GE: Yep, that’s correct.
Ard: So what did Fred Hoyle think when he came up with his…?
GE: Hoyle originally developed the Big Bang model as a way of avoiding a start to the universe which he thought had religious significance.
Ard: So the word ‘Big Bang’ comes from Fred Hoyle?
GE: The word Big Bang comes from Fred Hoyle, as a derogatory term. He developed a steady-state model which didn’t have a start because it was disproved by observations. But he then got in to thinking about these probabilities of life and all the rest of it, and eventually he made the statement that life was so improbable that it looked like a put-up job. And he used that kind of phrase, which was just a statement that life is very, very improbable. The universe has to be really fine-tuned for life to come into existence, and so from a scientific viewpoint there is something to be explained.
But let me just clarify something: when I say there is something to be explained, it doesn’t contradict any experiment; when I say there is something to be explained, it’s a philosophical thing that needs to be explained. Fine-tuning is a philosophical problem. It’s not a scientific problem in the sense that there’s an experiment which gives a result.
David: Because you’ve said there’s no way of testing the philosophy.
Ard: In some sense the science everyone agrees on. Everyone agrees that these constants are fine-tuned. It’s what that means that they disagree on.
GE: Correct. It’s what that means which is a philosophical issue. And so it’s a meta-scientific question.
Ard: But that’s an important thing to talk about.
GE: It is. The problem is that some of my colleagues are writing about it as if it can be solved on a purely scientific basis, and I think this is very misleading to the public, and I think it’s very misleading within the scientific community. I think it’s a problem when scientists present a philosophical statement and claim it can be tested or proved scientifically.
‘An abstract logic has physical outcomes in the real world. Abstract entities are driving the physics at the bottom level. The physics is not controlling what happens.’
TranscriptArd: We’re going to switch topics. That was great. That was really helpful.
David: Reductionism?
Ard: So why don’t you ask about reductionism because that’s the one you’re… So we’re interested in emergence and reductionism.
David: We’ve gone around asking everyone about the two and trying to get them to define both.
GE: And you’ve got 150 different answers.
David: You said it George. So would you like to add one more?
David: And I should stress, we’re not trying to be in any way anti-reductionistic. We’re just saying, what are they? What are its strengths? What are its weaknesses? Is it the answer to everything or not?
GE: Reductionism is the question: can you, in principle, completely explain what happens at the higher levels in terms of what’s happening at the lower levels?
David: And what do you think?
GE: Well my answer is absolutely not.
David: Why?
GE: I think a very good place to start is digital computers because digital computers are something which we can actually understand fully. Now a digital computer, it’s made up of all of these gates, transistors joined together by wires and then put together with a keyboard and a display and so on, and you can look at it at the different levels. At the bottom-most level it’s electrons flowing through the gates in a particular way, and that’s what controls what happens at the screens.
But given that hardware – there’s the hardware sitting there – it doesn’t do a thing until you load it up with a program, and what the identical hardware does is completely different depending on the software you load. So if you put in a word processing program, a music program, a paint program or something, you have completely different outcomes from the identical hardware. So the hardware, per se, does not determine what happens. What determines it is the program you load in. So now the question is, what is the ontological nature of a digital computer program?
David: When you say ontological…?
GE: What kind of existence does it represent? And now the hard-line reductionist will say that it’s nothing but electron states in these gates. Now that is completely wrong, and a useful side-step here is to think about what is the ontological nature of a book.
Now in the old days we all thought of a book as paper with printing on it and covers, and that’s a book. Now the question is, is it the same book if it’s got a different size print? Is it now still the same book? Is it the same book if you print it in italics or not? And I think we all agree it’s the same book. It’s different instantiations of the same book.
Nowadays we know that the book can be given to you in electronic form. Is the electronic form still the same book? And my answer is yes. The book is the abstract quantity which can be instantiated in those different ways. Now a computer program is the same: it’s an abstract entity; it’s not a physical thing. And so some people say, ‘But it’s here: it’s the CD disc.’ But it’s not the CD disc. Is it the excited states in the gates? That’s an instantiation of the computer program. And actually a computer has got layers of structure: there’s the machine language, the assembly language, there’s the operating system language, there’s the high-level language, and what is the key thing here is that there’s a logic in the computer program.
That abstract logic then gets written into a high-level code. What happens in the computer is absolute magic. The high-level code gets typed in and then interpreters or compliers write it down in to the lower-level languages.
Exactly the same logic is present at every level, but it’s represented in a different way with different rules, and at the bottom level it gets turned into instructions at the gate, and it gets turned into electronic states in the gates. Now, what is the computer program? It’s the equivalent class of all of these representations: it’s an abstract thing. Does it have causal power? Yes, it causes things to happen.
And very, very similar to this is the rules of chess and the rules of football. Those are abstract agreements and they can change with time. Now, the rules of chess determine what happens on the chess board, and I like to imagine this Martian coming and watching chess – after a while he works out these different motions, and then he picks up the rook and he looks underneath it. ‘Is something causing it?’ And then he can’t figure that out, and so he invents a force field which acts on rooks and only enables them to move in different force fields…
David: Looking for a physical explanation?
GE: Looking for a physical explanation. It’s a mental explanation. It’s a set of rules, abstract rules, and again they’re abstract, they’re not physical things. And they can be realised in a computer program or in your mind, or they can be realised in a book and so on. And again this multiple realisation, whenever you’ve got multiple realisation of some concept, it’s telling you that there’s causation from the concept to all of these realisations.
David: So you’re saying an abstract logic has this power?
GE: An abstract logic has physical outcomes in the real world through being what is implemented in a computer. So then, of course, the old philosophers of mind would say, ‘but you’re talking a dualist position.’ My answer is, ‘yes I am.’ A computer is a dualist machine: there’s the hardware and the software.
David: So you’re saying there’s a difference between the mind and its ideas, and the brain?
GE: Yes, I take the completely unpopular position: I’m a dualist. There’s the mind and the brain, and the mind inhabits the brain… or thoughts, thoughts inhabit the brain and thoughts are not physical things. Thoughts are abstract things which get represented in a physical way.
And again we do not understand how this happened, but the brain has a hierarchical structure. Thoughts have a hierarchical structure, and in the computer you can see these different levels. You can understand them, and you have got these interpreters or compilers which do it. I think eventually when we understand the brain enough, we will see exactly the same kind of structure happening in the brain.
The logic is going top-down from the top level down to the bottom and it is the logic which is controlling what happens at the bottom level. Abstract entities are driving the physics at the bottom level. The physics is not controlling what happens.
David: So that is exactly the opposite of when people say the reductionistic picture is always once you’ve understood these things at the bottom, they are what cause things to happen?
GE: Yep.
David: The cause always runs from the bottom up?
GE: Well it goes both ways, and there’s a large literature on what is called supervenience.
David: What is supervenience?
GE: Supervenience is if I knew everything about the bottom-level state – and let’s take the computer as an example – so I know the wiring and the chip; if I knew at an instant all of the states of the electronic gate, and then I reproduced it over there in another computer in exactly the same way, then it would give you exactly the same high-level stuff there. So at that level the reductionist picture is correct.
But the question is, how did those bottom-level states get to be in the excitation states that they are? And that can only happen top-down from the logic controlling what happens at the bottom level. And something similar like that will be happening in the mind.
David: I was just thinking about why so many scientists are really wedded to reductionism, and is it because they think the only thing that you could add into the universe, that isn’t what the reductionist story has in it, matter, that they think you’re going to import the supernatural? Whereas you’re importing something that is not supernatural. You’re saying there’s a realm of ideas, which isn’t supernatural.
GE: No, it’s not supernatural in that sense. The ideas don’t reach down and act of themselves.
David: No.
Ard: Like ghosts.
David: No, true, okay.
‘My definition of a fundamentalist is someone who takes a partial truth and claims it’s the total truth, and that’s exactly the problem here.’
TranscriptArd: I remember when I first learned basic statistical mechanics and how to calculate ideal gas law from the interaction between the atoms, and then I began to calculate more complicated gas laws and then equations of states. It’s a very powerful and beautiful thing.
GE: Yeah, it’s beautiful.
Ard: And so it’s not so surprising, sometimes, that if you’ve had that experience, you think this is the best way of understanding the world.
GE: Yeah. And in my view, the scientifically legitimate thing is to try and extend that as far as you can, so you can see the widest domain that you can explain by it. The problem comes if you try to say this is the only thing which is happening; it’s the only kind of causation that is possible. That’s where the problem comes.
And so I have this definition of a fundamentalist. My definition of a fundamentalist is someone who takes a partial truth and claims it’s the total truth, and that’s exactly the problem here.
If you say that statistical physics explains a lot of stuff, there’s absolutely no problem. If you claim it explains everything, including life, it’s simply not true. And I think a lot of the problem here is that the people who are wanting to say that all we’ve got is the bottom-up causation... they are just… one should pursue bottom-up causation as far as one can, and it’s very powerful, but it’s not the only thing in existence.
In fact I make quite a strong claim there. If you want to create life, there’s a level, a ceiling that you can reach by bottom-up assembly of molecules and so on, and you can’t get any further for one very simple reason: after a certain time, adaptive selection has to come and you’ve got to start adapting to your environment. Now when that happens, the environment has to feed in signals to this organism which will change either its structure, or its behaviour, or both.
Now, that’s top-down causation from the environment into the structure of the organism at the macro level in your organism and down to the electrons and protons in the organism. If that top-down causation does not come into existence, you can’t get life, and so I make a strong statement that purely bottom-up causation will not bring life into existence.
David: Ah, that’s very interesting. Because you are saying it feeds information in, and you have said that before: information is the new thing.
GE: Yeah, what’s DNA about?
David: Life is information: it’s coding. And information is a real thing, but it’s not physically real is it?
GE: No.
David: Because the information is different from the way that it’s encoded.
Ard: And the information is coming in from the environment.
David: That’s fantastic.
GE: The whole point of DNA, the wonderful discovery of DNA, is that it can, like a Turing machine, it can encode any protein structure you like, any one at all, and the physics doesn’t determine which comes out. So if you’re a tele-physicist, predict for me what the DNA sequence is going to be. You’ll shrug and say, ’I can’t do it’, because this ain’t physics, it’s biology. It’s a different logic, as it were.
David: So is that an emergent level then?
GE: Yes, absolutely. But why people believe in reductionism is the unbelievable success. And you experience it, as you were saying, with the kinetic theory of gases. It works absolutely beautifully. The atomic structure of matter has been a huge success. Then there was the physical structure of chemistry. The wonderful, wonderful discoveries of Linus Pauling and all these people of how chemical structure emerged, the quantum physics. Wonderful success.
Then there was the molecular biology revolution with Crick and Watson and so on, and life is molecules interacting with each other, and there’s this DNA coding and so on. Wonderful.
And then there was the whole thing of neurons and how you could understand the mechanism of the brain in terms of electronic impulses going down axons and dendrites according to laws which are perfectly understandable in terms of the underlying physics.
And so the reason people pursue it is because it’s been so incredibly successful in a most extraordinary kind of way. But, in each of these areas, there’s always been a counter-reductionist thing, like in the case of statistical physics. The arrow of time is still a worm at the bottom of the thing in the case of statistical physics. In the case of chemistry, chemistry is a success in principle but not in practice.
In the case of the genes there’s been the whole epigenetic thing coming back and saying causation is not only bottom up. Epigenetics is the solid statement there’s a mass of top-down causation. And in terms of the mind, you find you cannot understand the mind in bottom-up terms only.
‘Emergence is when you put simple things together and new behaviours emerge. Can you explain them all in terms of the lower level? Weak emergence is where you can. Strong emergence is where you can’t. I believe both exist.'
TranscriptDavid: Can I ask about… various people have mentioned to us, they’ve said there’s weak emergence and strong emergence. What are they and what’s the difference?
GE: Okay, emergence is when you put simple things together to create much more complicated things which have got behaviour which is completely different from the simple things which you put together. So new kinds of behaviours emerge at the higher level structures you create out of these simple things. And so just as an example: each of us are made out of atoms, of protons, neutrons, electrons, but what we get at the level of the body, the mind, is completely different from what you had at lower levels.
Roughly speaking, weak emergence is where new powers come in but you can explain them in terms of the lower level, and strong emergence is where you can’t.
David: Right. Which one do you believe in? You believe in strong emergence?
GE: I believe both exist. For instance, I just believe, as I have made very clear, the mind can emerge and that requires top-down causation and you can explain all of the properties of the brain in terms of the physics of the molecules, the neurons and all the rest of it, but you can’t explain the ideas in there. And so those ideas are strong emergence. And so, in my view point, it’s absolutely clear: strong emergence occurs and has physical causes.
David: And so that phrase that Rosenberg uses, where he says the physical facts fix everything?
GE: It’s not true. But, you see, what is true is once these ideas have been incorporated in the brain and we learn them, then they get built into the connection strengths in the neuron. Once that has happened, then it is reasonably plausible that a totally identical brain with totally identical strengths and totally identical excitations at that instant might experience the same thoughts. But the point is, you can’t get to that state without top-down causation.
I believe that as complexity arises, higher level rules come into being which were not implied by the lower level. Just as a very, very simple example. Physics talks about interaction between particles, forces, electromagnetic and strong and weakened direction. A little bit up, you get bacteria and amebae where the rules that come in there are Darwinian selection.
David: You’ve got life.
GE: Yes. Physics says nothing about Darwinian selection. A new principle has come into being.
David: Is that a level or emergence then?
GE: Yes.
David: So you have physics and chemistry, and then at some point they manage to create something which is then life, which has its own rules.
GE: It has its own rules, and those rules are governed by information. One of the things which comes into existence is information, which didn’t exist at the lower level. But the rules by which the information acts come into existence.
David: Right, yes, DNA, for example.
GE: And at a higher level abstract thought comes into existence, and all the possibilities that thought allows come into existence.
David: Right, so then in my world you’ve got physics and chemistry, which gets more and more complicated until it creates an emergent level of life.
GE: Yes.
David: And then natural selection is building more and more complicated things until eventually it creates minds which can see or touch that level of ideas.
GE: But these are what are called the major transitions in the evolutionary history. They’re not transitions just of… They’re transitions of quality. The quality of what happens changes completely. And I think what is very important here is the following: my scientific colleagues listen to me and say, ‘Never-the-less, I believe if you knew everything about the universe at the time of the Big Bang, you could predict everything that happens today.’
David: No, do they really say that?
GE: Well, yes.
David: I thought that went out a couple of hundred years ago. Do people really say that?
GE: I’ve had a Facebook interchange with a very, very interesting colleague who claimed this a couple of months ago.
David: But that’s untenable. Surely then he is saying the reason that you would say the answer to 2+2 is 4 has got nothing to do with mathematics. It’s because some quark and electron headed out from the Big Bang bumped, and it was always going to make you say 4.
GE: That’s right.
David: That’s crackers, isn’t it?
GE: I’m just completing this book on top-down causation in which I had some derogatory comments about this. I said it was ‘ludicrous’, or some word like that, and the reviewer of the book said, ‘How can you use the word “ludicrous”’? You’re a scientist.’
David: But it is ludicrous, don’t you think?
GE: It is ludicrous. The idea that everything that we would be saying, the idea that the theory of relativity and the Battle of Waterloo was written into the Big Bang, is just ludicrous.
‘Do we invent mathematics or do we find mathematics? I’m an unashamed mathematical Platonist: we discover mathematics.’
TranscriptDavid: So this is something that Ard and I were discussing earlier. Are you saying that when I ask you what does two plus two equal, and you say four, it’s always seemed to me the reductionistic argument – when they say, well, consciousness doesn’t exist – is that somehow you come up with the answer four because you were forced to because electrons just got into that state? Whereas I’ve always thought that the reason you say the answer is four is because of the logic of mathematics. So, in other words, it’s the logic of mathematics which is pushing the electrons around, not the other way, where the electrons are forcing you to have a thought.
GE: No, you’re quite right. That’s exactly the way it is.
David: Okay, so he does agree with us. Because we were discussing this earlier, and then we thought, crikey, maybe we’ve both really misunderstood it.
GE: Do you want me to open this up to an even more mind-boggling place?
David: Go on then.
GE: Okay. Where does the logic of mathematics come from?
David: Oh dear.
GE: This is the old question: do we invent mathematics or do we find mathematics? And I’m an unashamed mathematical Platonist: we discover mathematics. Two plus two is four is too simple. Let’s take something more interesting like the fact that the square root of two is irrational. Now the square root of two is irrational no matter whether you’re an Ancient Greek or someone here or someone on Mars. The square root of two is irrational. It’s a timeless, eternal, unchanging mathematical truth. In other words it’s a Platonic kind of statement.
The ontology is the mathematics exists and is there and is unchanging. The fact that the square root of two is irrational is an eternal unchanging truth. What we understand about it is a historically contingent thing, and we didn’t know that 10,000 years ago and we do know it now.
David: But the thing which is true was always true?
GE: The thing which is true is always true and has been true since the beginning of the universe.
David: Right, so in other words it was true when there were only dinosaurs around, and it’s still true.
GE: It was true at the start of the Big Bang. It was true before, when there was just hot gas and nothing else.
Ard: I mean, if you think about it that way, it’s really hard to believe that wouldn’t be the case.
David: Except that if people, physicists, would say look, ‘I’ve got bosons and I’ve got quarks, you know, what is the particle that carries the idea?’ That’s what...
GE: Yeah, but physicists have great trouble telling you this famous question. Why does mathematics underlie physics? The famous thing that Galileo said that the nature of the universe is written in mathematics. And Wigner and Penrose and other people have pondered, why is it that physics can be written in mathematical terms? And that’s a deep philosophical question for which we don’t have a proper answer.
Ard: So the unreasonable effectiveness of mathematics?
GE: The unreasonable effectiveness of mathematics, yes.
‘That space of abstract stuff was sitting waiting to be discovered and eventually minds reached a sufficient complexity that they could discover it.’
TranscriptArd: So that kind of raises another really interesting question, because there are these abstract truths, like the truths of mathematics, the world of ideas. Where do those come from?
David: You said where this time.
Ard: This time I said where. Where do they come from? I didn’t say, ‘where are they?’ But, ‘what is their cause?’
GE: What is the cause of those mathematical logical truths?
Ard: Yes, exactly.
GE: It’s the nature of logic is all I can say. That is the way it is.
David: You see, for you, it’s God.
Ard: I think it comes from God.
GE: God? Okay, well I’m prepared to say that that is one possibility. There’s an alternative possibility, which is that God has to obey…
Ard: Obey the law of logic.
David: God is one of the ideas in your realm of ideas.
Ard: Well no, there’s a long argument among theologians and philosophers…
GE: I’m sure there’s a long argument with theologians.
Ard: …whether the laws of mathematics are created by God, or whether God, in fact, has to obey the laws of mathematics. So, for example, you might say, even God can’t make a square circle because it’s a non-logical. It’s law of non-contradiction. But the interesting point is that here we have these abstract, non-physical realities that have causal powers in our world. We think of God as a non-physical, abstract entity who has causal impact on the world, so there’s some analogy there. And once you hold that there’s one kind of non-physical reality, then it’s not so strange to think there might be another kind.
GE: That’s this kind of theology which I avoid.
Ard: You avoid theology?
GE: Yeah, I avoid theology.
GE: From my view point, existence isn’t just physical existence: there’s these abstract existences. So then you should ask me in philosophical terms how do I justify the word existence? And I’ve got a very simple answer to that. I take the existence of physical entities, like we’re seeing in this room, as being real – that’s my starting point – and I take the hierarchy of this to be real. So, in other words, this thing is made up of a metal ball, which is made up of atoms, which is made up of quarks. I believe that the ball is real, as well as the atoms are real.
I think just because it’s made of atoms doesn’t mean that it isn’t a real ball. So that physical hierarchy is real. Then I say that anything else which has a demonstrable causal effect on here must also be real.
David: Ah, so your ideas?
GE: Otherwise you have uncaused entities in the world.
David: Right.
GE: I’ve got in my hand a pair of spectacles. Now, how did they come into existence? Someone had the idea of a pair of spectacles and then created these by a machine, and so on. If they hadn’t had that idea, this wouldn’t exist. So that idea has to be real too, even though it’s not a physical entity.
The generic way to think about this, the deep structure of cosmology, is possibility spaces. Now, physicists like to talk about physical laws, but you can talk about the laws, or you can talk about what is possible given those laws. And actually, in many ways, it’s better to talk about what’s called a phase space, or a Hilbert space.
Once you start the line of argument I’ve been giving, there’s a mathematical possibility space. It’s a space of possible logical arguments and outcomes. If you now keep pursuing this line of argument, we can only think a thought because it is possible to think the thought. That sounds like a meaningless tautology, but actually what it means is the following: there is a set of possible thoughts which is up there in some Platonic space. You can’t think a thought unless it’s one of the thoughts which can be thought because it’s a logical possible thought.
David: So that realm of ideas your talking about, you would say that came into existence in the Big Bang along with… along with the…?
GE: I wouldn’t necessarily say it came into existence. I think it might in some sense pre-exist the big bang.
David: Oh, okay. Pre-exist. But it exists, so then what natural selection is doing was creating more and more complicated minds, or brains, rather, and at some point they can access this realm?
GE: That is correct, and so that space of abstract stuff was sitting there waiting to be discovered, and eventually minds reached a sufficient complexity that they could discover it. But that space doesn’t need minds to exist, it’s there.
David: It’s there already.
GE: Yeah. There’s a wonderful book out of this by Paul Churchland called Plato’s Camera.
David: Yes, I’ve read it.
GE: And Plato’s Camera talks about, in detail, how the structuring of the mind as a neural network enables us to recognise Platonic patterns, and they then get incorporated into electronic patterns in the brain, and then they can go down and effect what happens in the real world. So I see this causal link from Platonic spaces into intelligent minds, into electrons. It’s a downward causation, and then into causing effects in the real world.
For instance Pythagoras’ theorem is used by surveyors and architects. Or the number Pi is discovered, and it’s then used by engineers and it changes what happens in the real world because it’s used in engineering design.
David: So ideas have some kind of existence in our universe. It’s just it’s not a, sort of, physical existence like wood or steel.
GE: Yes, that’s right.
‘Do I think that there is a space of moral reality? And my answer is yes. I believe that the holocaust was an evil. I think that’s a fact, a moral fact.’
TranscriptDavId: If you’re saying then that mathematical ideas exist in our universe in some way…
GE: In some abstract way.
David: In some abstract way, could other kinds of ideas exist in the same way? Could there be moral ideas that were there? I’m not advocating that there are, but it occurs to me if you say, well, the square root of two was always there, by what authority would you say, well, moral truths couldn’t be?
GE: Now we’re getting to interesting territory here. The fact that it is possible to think of moral thoughts is a very, very deep fact about the universe: the fact it’s possible to think that things are good and evil, bad and so on.
And then my direct answer to your question is, do I think that it could be that there is a space of moral reality? And my answer is yes. I’m a moral realist. I’ve written a book about this called On the Moral Nature of the Universe with my friend Nancy Murphy, and we defend strongly the idea of a moral reality.
Now what you have to do there is then say, well, what is the nature of the moral reality? And you then have to realise that the simplistic views of morality are not correct. Real morality is not a set of ten laws on a tablet which you can write down, because those are a terrible approximation to the real thing, and from my viewpoint, the deep nature of reality, which is discovered by the spiritual members of all the great traditions in the world, is that the deep nature of morality is to do with self-sacrifice and giving up on behalf of other people. It’s counter-intuitive. It’s not a logical argument, and people are looking for logical laws that they can apply. But the deep nature of morality, from my position, is that it is the counter-intuitive thing: that if you want to get something, and create greater good, you must give up, and the way to getting what you want is giving up what you want, and that’s the way to get what you want.
The religious literature has known this for thousands of years: the fact you feel good about something doesn’t mean that it is the good thing to do. Good and evil is not scientifically measurable and so it’s not a scientific concept.
Ard: But the point is just because you can’t measure it scientifically doesn’t mean that it’s not true.
GE: Oh, I think it’s true. As I say, I think there’s a moral reality. I believe passionately that apartheid in South Africa was an evil. I believe that the Holocaust was an evil. I think that that’s a fact, a moral fact.
Ard: And you were involved in the anti-apartheid movement. Do you want to tell us a little about that?
GE: Well that’s a whole other story.
Ard: But you passionately believed…
GE: I believed that it was morally wrong what was going on. Not that it was socially wrong or that it was politically wrong, but that it was wrong, fact.
Ard: And that motivated your anti-apartheid…
GE: Yes.
David: And the way that you are describing moral facts, you would have felt that that was a moral fact that apartheid was wrong with the same certainty and power as the square root of four is two. They are both truths.
Ard: And there are people, surely, in your social class or in your friendship groups who believe apartheid was fine?
GE: Yes, yes.
Ard: So you would say they are wrong?
GE: There certainly were people who thought in various ways it was right, and I happened to believe they’re wrong. Now it’s not a scientific thing: I cannot prove scientifically they were wrong. It’s a moral or philosophical understanding, and so if you say prove it, I can’t prove it. All I can say is it is my belief that this is the way things are.
Ard: But if you say, ‘Oh, it’s my belief, I can’t prove it’, that sounds like you’re taking a step back and saying, ‘This is my belief. Your belief is that apartheid is fine, and, you know, let’s leave it that way.’
GE: My belief is that there is an abstract moral standard.
Ard: And do you think that in the anti-apartheid movement this idea that it was wrong, and that that was a fact, played a big role for those who fought against apartheid?
GE: Oh, I think so.
Ard: People sacrificed for this?
GE: Absolutely. I mean the point about this is exactly that. I take someone like Desmond Tutu as being the classic person doing that. For him it was absolutely not the slightest question that it was an evil, and this wasn’t an opinion, but it was a fact that this was an evil.
‘There are many attempts nowadays to derive morality from science. They always introduce by the back door some concept of the good life which they take for granted without discussion.’
TranscriptArd: People are often nervous about the idea there is moral truth out there.
GE: Yes.
Ard: And they’re nervous because they worry that you’ll use that to hit them over the head.
GE: What?
Ard: You’ll use that to whack them.
David: And say it must be like this.
Ard: It must be like this. And others say, ‘Well, you know, our morals can be explained on evolutionary grounds; evolution gives us morals.’ What do you make of that?
GE: There are many attempts nowadays to derive morality from science. Some are from evolutionary grounds, some are from neuroscience, and so on. They always introduce, by the back door, some concept of the good life which they take for granted without discussion, and they assume that’s the right thing. They then go on to talk about morality arriving out of evolution. So, for instance, the fact that people have behaved in a certain way does not mean it’s a good way to behave, and so a lot of people say because people did that, it’s good. People try to say because it promotes people living together, it’s good. Well, who said that people living together is good? It may be good for survival, but it’s not the same as good in an ethical sense.
Now, for instance, a book called The Moral Molecule is based on the idea that a good life is a happy life. Well, if a good life is a happy life, we can solve it by giving everybody drugs and we’ll all feel happy. And then is that a moral life? Of course it isn’t.
Ard: Can science explain morality? It’s very natural. You look around you – you see technology, how it’s changed our lives, medicine, how it’s made our lives better, healthier, in really dramatic ways, and that has come through the power of science.
GE: Yes.
Ard: And so it’s very natural to think we’re going to use those same methods and solve the perennial problems of what is the good life.
GE: Well there’s a very different question. Will science solve the problem of what a good life is? Or will it help you to live a good life once you’ve decided what it is?
Ard: Exactly.
GE: Okay, science can do the second, to some extent, although, of course, technology is only a fraction of the solution: a huge part of living the good life is to do with psychology, sociology, philosophy, ethics, and so on.
Can science tell you what a good life is? My answer is an unequivocal, no. There’s no chance science can tell you what a good life is, because there’s no scientific experiment for what is good and what is bad.
And as I’ve said already, whenever people claim they’ve got an explanation from evolutionary theory, or genetics, or neurobiology, they always import, behind the scenes, a concept of what the good life is, and they don’t tell you they’re doing it. They take it for granted, and you have to learn to challenge them when they say this is what will make you make things good, and you have to challenge them: ‘Well, how do you know it’s good?’
And they will keep on coming back to you with some assumption about what is good and what is bad, and that is what science cannot do.
Morality is a completely different dimension. Science can explain what I would call the lower reaches of morality. It can explain certain behaviours which tend to enable societies to live together. To call that good or bad, it’s simply... it’s the wrong dimension. It’s not a moral dimension.
‘When they say the universe is meaningless, the hidden agenda is to ignore all of the data from human life, human history, from the great literature, the great art, all the rest.'
TranscriptDavid: I wanted to ask a related question, because it’s come up a lot. There’s the reductionist side of things. They’re also fond of saying, ‘Look, there’s no such thing as meaning; things don’t mean anything. There’s no meaning in this, no ultimate meaning in the universe.’ And I’m just wondering what you think about that?
They paint this picture saying, ‘You know, our position is meaningless, and we’re one species, on one planet, round one sun, and the laws the universe is governed by have no meaning.’
GE: The laws have no meaning. What actually is happening here is the following, and I’m seeing it with a lot of my scientific colleagues. There’s a lot of data about the universe. Basically what is happening with these guys is they’re saying if you want to understand the universe, you must take data from microscopes, telescopes, particle accelerators. You must take that scientific data, and that will tell you the nature of the universe.
When they say the universe is meaningless, the hidden agenda is they are saying, ‘We choose to ignore all of the data from human life, human history, from the great literature, the great art, all the rest of it. We choose to say that that has nothing to tell you about life and the universe, because we think the only evidence that matters is the matter that the hard science can tell you.’ They’re arriving at that position by ignoring all of the data they find inconvenient.
David: Yes. So their conclusion is already there in their assumptions about what counts as evidence.
GE: Yes. And, of course, with these people, they either live a totally bipolar life where they have these theories over there, and then they go to their family and say, ‘Hello’, and life is all meaningful, and they pat the dog and play with the child, and all the rest of this. Or they don’t, in which case their home life must be bloody hell.
I think one of the things which is a simple fact is that there is meaning in the universe. Now, where or how that meaning arises is something we discuss, but the fact that there is meaning in the universe is, I think, absolutely…
David: And it gets back to fine-tuning, because I always imagine all the universes, and I was thinking if your god had to find the universe again, it would need to have little signs by them: ‘This is the universe that’s got life in it.’ And I think the word that God would write down on the flag attached to our universe would be meaning. It’s not just fine-tuned for life, it’s got meaning in it.
GE: Well, you see, it starts off much earlier than that. All of biology is to do with function and purpose in some sense. What is that information for? That information is all for a purpose. It’s for a purpose of reproduction, of getting food, of sensing things. So life is about purpose.
David: So not only is there meaning in the universe, you’re saying there is purpose as well?
GE: There is purpose in the universe. I’m not saying it’s built into the laws of physics. It’s not built into the laws of physics, but it comes into existence, and there isn’t any question it comes into existence. How does it come into existence? Well, my position on that is that the possibility of meaning is built into some of those possibility spaces. The possibility of meaning was there before the universe came into existence, and so therefore, in a sense, the universe was expecting meaning to arrive. And I think that that is, once you start thinking about it, a logically incontrovertible position. There is meaning in the universe. That is only possible if it’s possible to have meaning, which means one of those possibility spaces I’m talking about had the possibility of meaning in it.
So the deep question, the deep question of cosmology, is why are those possibility spaces what they are? And the theological position is very persuasive in many ways for this, because the purely physical argument doesn’t begin to touch a lot of what is going on in the universe we see around us in our daily lives.
Ard: I think that’s right. You need to think theologically.
David: No! No! George is saying the opposite! I don’t need to think theologically. I don’t need God. I just need to have this realm of ideas, which is where…
Ard: But the question is, where did this realm of ideas come from? The theological explanation makes the most sense.
GE: I think you can defend with absolute certainty, as it were, once you’ve thought this through, the existence of these possibility spaces. If you ask where do they come from, you’re then in a realm of speculation where everything is right open and I…
Ard: We think a theological explanation is a good one but you don’t, yeah, as long as you… you don’t have to buy into that if you don’t feel it.
GE: If you have someone who says there is no meaning in the universe, I can only say they are just ignoring all of everyday life.
David: That’s the feeling I’ve had all along.
GE: If you want to ignore all of everyday life, that’s fine, but then don’t tell me you’ve got an adequate theory of the way the universe is because you haven’t.
David: Yeah, that’s exactly how I felt all along because it does feel like just explaining away the things which your present bit of science has a difficulty explaining, it just seems to be not…
GE: It’s one of those tricks: someone tells you what questions you’re allowed to ask and what you’re not allowed. Where do they get the authority to tell you what questions you’re allowed to ask and what you’re not allowed to ask?
George Ellis is Professor Emeritus of Complex Systems in the Department of Applied Mathematics at Cape Town University, South Africa. His work covers a very broad field ranging from cosmology and mathematics to the emergence of complexity and the role of top-down causation in evolution. His books include: The Large Scale Structure of Space-Time, written with Stephen Hawking; On The Moral Nature of the Universe, and How Can Physics Underlie the Mind? Top-Down Causation in the Human Contexts.
A winner of the Templeton Prize in 2004, he was an active and life-long opponent of apartheid and was awarded the Order of the Star of South Africa by Nelson Mandela in 1999.
The idea that everything that we would be saying, the idea that the theory of relativity and the Battle of Waterloo was written into the Big Bang, is just ludicrous.
There are many attempts nowadays to derive morality from science. Some are from evolutionary grounds; some are from neuroscience, and so on. They always introduce, by the back door, some concept of the good life which they take for granted without discussion, and they assume that’s the right thing.
‘It’s one of those tricks: someone tells you what questions you’re allowed to ask and what you’re not allowed. Where do they get the authority to tell you what questions you’re allowed to ask and what you’re not allowed to ask?’
Ard: Could you explain to us the concept of fine-tuning in cosmology?
GE: Okay. Well as a cosmologist one imagines imaginary universes, counter-factuals, and tries to see if you can learn anything. And if you imagine other universes, not only will they be bigger or smaller, expanding faster or slower and so on, but they can have different laws of physics. Because one of the things as a cosmologist one wonders about is, why are the laws of physics as they are?
So if you imagine the other laws of physics, you can ask how different can the laws of physics be and still enable life to exist. And it turns out there are a great many ways in which if you vary physics, pretty soon life cannot exist. And so there’s what’s called fine-tuning, namely that physics has to lie in a very restricted range in order that we, living beings, can come into existence. And it focusses, in particular, on something called the fine-structure constant, which is basically the strength of the electro-magnetic force, and the cosmological constant, which is how fast the universe is accelerating at the present time. And in either case you can show if they lie outside of a rather restricted range, in the one case, atoms won’t exist and therefore we won’t exist, and in the other case galaxies, and therefore planets won’t exist, and therefore we won’t exist.
David: I once heard you talk about Fred Hoyle in this. Could you tell me that story?
GE: The famous story about Fred Hoyle is he was one of the early people trying to work out how the elements out of which we are made come into existence, and he was particularly concerned about carbon.
In order that carbon exists, there has to be this excited state in the carbon atom. Now it turns out that the existence of that state depends on the fine-structure constant, and so there’s a link from the fine-structure constant through to this excited state, through to the fact that carbon is created in stars and thereby enables us to come into existence.
So if you imagine universes scattered around with all sorts of values of these constants, almost none of them will allow life: you have to lie in this very narrow band.
David: And how do you account for that then?
GE: How do you account for it? Okay, there are popular and unpopular versions. You can do it in three ways. One is to say it’s just chance: the universe just happens. Now, by chance I don’t mean it’s probable: it’s not probable or improbable, it’s just the way it happened. Now that’s a philosophically impeccable solution, but people don’t like it because it doesn’t get you anywhere.
David: It’s not much of an explanation is it?
GE: It’s philosophically impregnable.
David: Okay.
Ard: You say it just happened, and that’s it. If it didn’t happen then we wouldn’t be around.
GE: The second one is to try to say it’s probable. Now how do you try to say it’s probable? Your problem is there’s only one universe with one value. So if you can imagine an ensemble of universes which actually exist, they don’t exist in your mind but they physically exist, in some of them life will be able to come into existence.
David: Is that what people call the multiverse?
GE: That’s the multiverse and this is the scientifically preferred version of Martin Rees, Steven Weinberg. A lot of people prefer this.
Ard: So there would be just many, many universes?
GE: Yes.
Ard: So most of those universes would not have life, but if you have enough of them, eventually one of them will have life.
GE: I have a problem with this because if there is that multiverse out there, the question is, can you prove it exists? And in my view you basically can’t. So I think this is a philosophical but not a scientific solution to the problem.
Ard: So if you had the multiverse, if you had many different universes, enough universes that one of them would have life, do you think that would still need some kind of fine-tuning?
GE: Yes, because the problem just recurs at the next level. I can construct you a multiverse in which none of the universes exist. The multiverse, if it’s going to be sensible, has to have laws which create the multiverse. That’s going to have constants of nature in them, and some of those constants will allow the multiverse to allow it.
David: Otherwise you get the wrong multiverse?
GE: Yes, and so then, if you follow this up, you get multiverses of multiverses of multiverses.
David: As you say, it’s not getting you anywhere. You’re just pushing the problem back.
GE: Philosophically it doesn’t solve a thing, it just pushes you one step back. And then, of course, the final one is that the reason that the constants are what they are is that something, or some purpose, or some principle, or something, intended life to exist, which of course relates to the religious world view in some sense. It’s very unpopular in scientific terms, but again, philosophically, this is a perfectly viable position.
Ard: So you’re saying basically that the three possibilities are: happenstance, it just happens, just blind luck; or some kind of multiverse, or maybe some kind of providence?
GE: Yep, that’s correct.
Ard: So what did Fred Hoyle think when he came up with his…?
GE: Hoyle originally developed the Big Bang model as a way of avoiding a start to the universe which he thought had religious significance.
Ard: So the word ‘Big Bang’ comes from Fred Hoyle?
GE: The word Big Bang comes from Fred Hoyle, as a derogatory term. He developed a steady-state model which didn’t have a start because it was disproved by observations. But he then got in to thinking about these probabilities of life and all the rest of it, and eventually he made the statement that life was so improbable that it looked like a put-up job. And he used that kind of phrase, which was just a statement that life is very, very improbable. The universe has to be really fine-tuned for life to come into existence, and so from a scientific viewpoint there is something to be explained.
But let me just clarify something: when I say there is something to be explained, it doesn’t contradict any experiment; when I say there is something to be explained, it’s a philosophical thing that needs to be explained. Fine-tuning is a philosophical problem. It’s not a scientific problem in the sense that there’s an experiment which gives a result.
David: Because you’ve said there’s no way of testing the philosophy.
Ard: In some sense the science everyone agrees on. Everyone agrees that these constants are fine-tuned. It’s what that means that they disagree on.
GE: Correct. It’s what that means which is a philosophical issue. And so it’s a meta-scientific question.
Ard: But that’s an important thing to talk about.
GE: It is. The problem is that some of my colleagues are writing about it as if it can be solved on a purely scientific basis, and I think this is very misleading to the public, and I think it’s very misleading within the scientific community. I think it’s a problem when scientists present a philosophical statement and claim it can be tested or proved scientifically.
Ard: We’re going to switch topics. That was great. That was really helpful.
David: Reductionism?
Ard: So why don’t you ask about reductionism because that’s the one you’re… So we’re interested in emergence and reductionism.
David: We’ve gone around asking everyone about the two and trying to get them to define both.
GE: And you’ve got 150 different answers.
David: You said it George. So would you like to add one more?
David: And I should stress, we’re not trying to be in any way anti-reductionistic. We’re just saying, what are they? What are its strengths? What are its weaknesses? Is it the answer to everything or not?
GE: Reductionism is the question: can you, in principle, completely explain what happens at the higher levels in terms of what’s happening at the lower levels?
David: And what do you think?
GE: Well my answer is absolutely not.
David: Why?
GE: I think a very good place to start is digital computers because digital computers are something which we can actually understand fully. Now a digital computer, it’s made up of all of these gates, transistors joined together by wires and then put together with a keyboard and a display and so on, and you can look at it at the different levels. At the bottom-most level it’s electrons flowing through the gates in a particular way, and that’s what controls what happens at the screens.
But given that hardware – there’s the hardware sitting there – it doesn’t do a thing until you load it up with a program, and what the identical hardware does is completely different depending on the software you load. So if you put in a word processing program, a music program, a paint program or something, you have completely different outcomes from the identical hardware. So the hardware, per se, does not determine what happens. What determines it is the program you load in. So now the question is, what is the ontological nature of a digital computer program?
David: When you say ontological…?
GE: What kind of existence does it represent? And now the hard-line reductionist will say that it’s nothing but electron states in these gates. Now that is completely wrong, and a useful side-step here is to think about what is the ontological nature of a book.
Now in the old days we all thought of a book as paper with printing on it and covers, and that’s a book. Now the question is, is it the same book if it’s got a different size print? Is it now still the same book? Is it the same book if you print it in italics or not? And I think we all agree it’s the same book. It’s different instantiations of the same book.
Nowadays we know that the book can be given to you in electronic form. Is the electronic form still the same book? And my answer is yes. The book is the abstract quantity which can be instantiated in those different ways. Now a computer program is the same: it’s an abstract entity; it’s not a physical thing. And so some people say, ‘But it’s here: it’s the CD disc.’ But it’s not the CD disc. Is it the excited states in the gates? That’s an instantiation of the computer program. And actually a computer has got layers of structure: there’s the machine language, the assembly language, there’s the operating system language, there’s the high-level language, and what is the key thing here is that there’s a logic in the computer program.
That abstract logic then gets written into a high-level code. What happens in the computer is absolute magic. The high-level code gets typed in and then interpreters or compliers write it down in to the lower-level languages.
Exactly the same logic is present at every level, but it’s represented in a different way with different rules, and at the bottom level it gets turned into instructions at the gate, and it gets turned into electronic states in the gates. Now, what is the computer program? It’s the equivalent class of all of these representations: it’s an abstract thing. Does it have causal power? Yes, it causes things to happen.
And very, very similar to this is the rules of chess and the rules of football. Those are abstract agreements and they can change with time. Now, the rules of chess determine what happens on the chess board, and I like to imagine this Martian coming and watching chess – after a while he works out these different motions, and then he picks up the rook and he looks underneath it. ‘Is something causing it?’ And then he can’t figure that out, and so he invents a force field which acts on rooks and only enables them to move in different force fields…
David: Looking for a physical explanation?
GE: Looking for a physical explanation. It’s a mental explanation. It’s a set of rules, abstract rules, and again they’re abstract, they’re not physical things. And they can be realised in a computer program or in your mind, or they can be realised in a book and so on. And again this multiple realisation, whenever you’ve got multiple realisation of some concept, it’s telling you that there’s causation from the concept to all of these realisations.
David: So you’re saying an abstract logic has this power?
GE: An abstract logic has physical outcomes in the real world through being what is implemented in a computer. So then, of course, the old philosophers of mind would say, ‘but you’re talking a dualist position.’ My answer is, ‘yes I am.’ A computer is a dualist machine: there’s the hardware and the software.
David: So you’re saying there’s a difference between the mind and its ideas, and the brain?
GE: Yes, I take the completely unpopular position: I’m a dualist. There’s the mind and the brain, and the mind inhabits the brain… or thoughts, thoughts inhabit the brain and thoughts are not physical things. Thoughts are abstract things which get represented in a physical way.
And again we do not understand how this happened, but the brain has a hierarchical structure. Thoughts have a hierarchical structure, and in the computer you can see these different levels. You can understand them, and you have got these interpreters or compilers which do it. I think eventually when we understand the brain enough, we will see exactly the same kind of structure happening in the brain.
The logic is going top-down from the top level down to the bottom and it is the logic which is controlling what happens at the bottom level. Abstract entities are driving the physics at the bottom level. The physics is not controlling what happens.
David: So that is exactly the opposite of when people say the reductionistic picture is always once you’ve understood these things at the bottom, they are what cause things to happen?
GE: Yep.
David: The cause always runs from the bottom up?
GE: Well it goes both ways, and there’s a large literature on what is called supervenience.
David: What is supervenience?
GE: Supervenience is if I knew everything about the bottom-level state – and let’s take the computer as an example – so I know the wiring and the chip; if I knew at an instant all of the states of the electronic gate, and then I reproduced it over there in another computer in exactly the same way, then it would give you exactly the same high-level stuff there. So at that level the reductionist picture is correct.
But the question is, how did those bottom-level states get to be in the excitation states that they are? And that can only happen top-down from the logic controlling what happens at the bottom level. And something similar like that will be happening in the mind.
David: I was just thinking about why so many scientists are really wedded to reductionism, and is it because they think the only thing that you could add into the universe, that isn’t what the reductionist story has in it, matter, that they think you’re going to import the supernatural? Whereas you’re importing something that is not supernatural. You’re saying there’s a realm of ideas, which isn’t supernatural.
GE: No, it’s not supernatural in that sense. The ideas don’t reach down and act of themselves.
David: No.
Ard: Like ghosts.
David: No, true, okay.
Ard: I remember when I first learned basic statistical mechanics and how to calculate ideal gas law from the interaction between the atoms, and then I began to calculate more complicated gas laws and then equations of states. It’s a very powerful and beautiful thing.
GE: Yeah, it’s beautiful.
Ard: And so it’s not so surprising, sometimes, that if you’ve had that experience, you think this is the best way of understanding the world.
GE: Yeah. And in my view, the scientifically legitimate thing is to try and extend that as far as you can, so you can see the widest domain that you can explain by it. The problem comes if you try to say this is the only thing which is happening; it’s the only kind of causation that is possible. That’s where the problem comes.
And so I have this definition of a fundamentalist. My definition of a fundamentalist is someone who takes a partial truth and claims it’s the total truth, and that’s exactly the problem here.
If you say that statistical physics explains a lot of stuff, there’s absolutely no problem. If you claim it explains everything, including life, it’s simply not true. And I think a lot of the problem here is that the people who are wanting to say that all we’ve got is the bottom-up causation... they are just… one should pursue bottom-up causation as far as one can, and it’s very powerful, but it’s not the only thing in existence.
In fact I make quite a strong claim there. If you want to create life, there’s a level, a ceiling that you can reach by bottom-up assembly of molecules and so on, and you can’t get any further for one very simple reason: after a certain time, adaptive selection has to come and you’ve got to start adapting to your environment. Now when that happens, the environment has to feed in signals to this organism which will change either its structure, or its behaviour, or both.
Now, that’s top-down causation from the environment into the structure of the organism at the macro level in your organism and down to the electrons and protons in the organism. If that top-down causation does not come into existence, you can’t get life, and so I make a strong statement that purely bottom-up causation will not bring life into existence.
David: Ah, that’s very interesting. Because you are saying it feeds information in, and you have said that before: information is the new thing.
GE: Yeah, what’s DNA about?
David: Life is information: it’s coding. And information is a real thing, but it’s not physically real is it?
GE: No.
David: Because the information is different from the way that it’s encoded.
Ard: And the information is coming in from the environment.
David: That’s fantastic.
GE: The whole point of DNA, the wonderful discovery of DNA, is that it can, like a Turing machine, it can encode any protein structure you like, any one at all, and the physics doesn’t determine which comes out. So if you’re a tele-physicist, predict for me what the DNA sequence is going to be. You’ll shrug and say, ’I can’t do it’, because this ain’t physics, it’s biology. It’s a different logic, as it were.
David: So is that an emergent level then?
GE: Yes, absolutely. But why people believe in reductionism is the unbelievable success. And you experience it, as you were saying, with the kinetic theory of gases. It works absolutely beautifully. The atomic structure of matter has been a huge success. Then there was the physical structure of chemistry. The wonderful, wonderful discoveries of Linus Pauling and all these people of how chemical structure emerged, the quantum physics. Wonderful success.
Then there was the molecular biology revolution with Crick and Watson and so on, and life is molecules interacting with each other, and there’s this DNA coding and so on. Wonderful.
And then there was the whole thing of neurons and how you could understand the mechanism of the brain in terms of electronic impulses going down axons and dendrites according to laws which are perfectly understandable in terms of the underlying physics.
And so the reason people pursue it is because it’s been so incredibly successful in a most extraordinary kind of way. But, in each of these areas, there’s always been a counter-reductionist thing, like in the case of statistical physics. The arrow of time is still a worm at the bottom of the thing in the case of statistical physics. In the case of chemistry, chemistry is a success in principle but not in practice.
In the case of the genes there’s been the whole epigenetic thing coming back and saying causation is not only bottom up. Epigenetics is the solid statement there’s a mass of top-down causation. And in terms of the mind, you find you cannot understand the mind in bottom-up terms only.
David: Can I ask about… various people have mentioned to us, they’ve said there’s weak emergence and strong emergence. What are they and what’s the difference?
GE: Okay, emergence is when you put simple things together to create much more complicated things which have got behaviour which is completely different from the simple things which you put together. So new kinds of behaviours emerge at the higher level structures you create out of these simple things. And so just as an example: each of us are made out of atoms, of protons, neutrons, electrons, but what we get at the level of the body, the mind, is completely different from what you had at lower levels.
Roughly speaking, weak emergence is where new powers come in but you can explain them in terms of the lower level, and strong emergence is where you can’t.
David: Right. Which one do you believe in? You believe in strong emergence?
GE: I believe both exist. For instance, I just believe, as I have made very clear, the mind can emerge and that requires top-down causation and you can explain all of the properties of the brain in terms of the physics of the molecules, the neurons and all the rest of it, but you can’t explain the ideas in there. And so those ideas are strong emergence. And so, in my view point, it’s absolutely clear: strong emergence occurs and has physical causes.
David: And so that phrase that Rosenberg uses, where he says the physical facts fix everything?
GE: It’s not true. But, you see, what is true is once these ideas have been incorporated in the brain and we learn them, then they get built into the connection strengths in the neuron. Once that has happened, then it is reasonably plausible that a totally identical brain with totally identical strengths and totally identical excitations at that instant might experience the same thoughts. But the point is, you can’t get to that state without top-down causation.
I believe that as complexity arises, higher level rules come into being which were not implied by the lower level. Just as a very, very simple example. Physics talks about interaction between particles, forces, electromagnetic and strong and weakened direction. A little bit up, you get bacteria and amebae where the rules that come in there are Darwinian selection.
David: You’ve got life.
GE: Yes. Physics says nothing about Darwinian selection. A new principle has come into being.
David: Is that a level or emergence then?
GE: Yes.
David: So you have physics and chemistry, and then at some point they manage to create something which is then life, which has its own rules.
GE: It has its own rules, and those rules are governed by information. One of the things which comes into existence is information, which didn’t exist at the lower level. But the rules by which the information acts come into existence.
David: Right, yes, DNA, for example.
GE: And at a higher level abstract thought comes into existence, and all the possibilities that thought allows come into existence.
David: Right, so then in my world you’ve got physics and chemistry, which gets more and more complicated until it creates an emergent level of life.
GE: Yes.
David: And then natural selection is building more and more complicated things until eventually it creates minds which can see or touch that level of ideas.
GE: But these are what are called the major transitions in the evolutionary history. They’re not transitions just of… They’re transitions of quality. The quality of what happens changes completely. And I think what is very important here is the following: my scientific colleagues listen to me and say, ‘Never-the-less, I believe if you knew everything about the universe at the time of the Big Bang, you could predict everything that happens today.’
David: No, do they really say that?
GE: Well, yes.
David: I thought that went out a couple of hundred years ago. Do people really say that?
GE: I’ve had a Facebook interchange with a very, very interesting colleague who claimed this a couple of months ago.
David: But that’s untenable. Surely then he is saying the reason that you would say the answer to 2+2 is 4 has got nothing to do with mathematics. It’s because some quark and electron headed out from the Big Bang bumped, and it was always going to make you say 4.
GE: That’s right.
David: That’s crackers, isn’t it?
GE: I’m just completing this book on top-down causation in which I had some derogatory comments about this. I said it was ‘ludicrous’, or some word like that, and the reviewer of the book said, ‘How can you use the word “ludicrous”’? You’re a scientist.’
David: But it is ludicrous, don’t you think?
GE: It is ludicrous. The idea that everything that we would be saying, the idea that the theory of relativity and the Battle of Waterloo was written into the Big Bang, is just ludicrous.
David: So this is something that Ard and I were discussing earlier. Are you saying that when I ask you what does two plus two equal, and you say four, it’s always seemed to me the reductionistic argument – when they say, well, consciousness doesn’t exist – is that somehow you come up with the answer four because you were forced to because electrons just got into that state? Whereas I’ve always thought that the reason you say the answer is four is because of the logic of mathematics. So, in other words, it’s the logic of mathematics which is pushing the electrons around, not the other way, where the electrons are forcing you to have a thought.
GE: No, you’re quite right. That’s exactly the way it is.
David: Okay, so he does agree with us. Because we were discussing this earlier, and then we thought, crikey, maybe we’ve both really misunderstood it.
GE: Do you want me to open this up to an even more mind-boggling place?
David: Go on then.
GE: Okay. Where does the logic of mathematics come from?
David: Oh dear.
GE: This is the old question: do we invent mathematics or do we find mathematics? And I’m an unashamed mathematical Platonist: we discover mathematics. Two plus two is four is too simple. Let’s take something more interesting like the fact that the square root of two is irrational. Now the square root of two is irrational no matter whether you’re an Ancient Greek or someone here or someone on Mars. The square root of two is irrational. It’s a timeless, eternal, unchanging mathematical truth. In other words it’s a Platonic kind of statement.
The ontology is the mathematics exists and is there and is unchanging. The fact that the square root of two is irrational is an eternal unchanging truth. What we understand about it is a historically contingent thing, and we didn’t know that 10,000 years ago and we do know it now.
David: But the thing which is true was always true?
GE: The thing which is true is always true and has been true since the beginning of the universe.
David: Right, so in other words it was true when there were only dinosaurs around, and it’s still true.
GE: It was true at the start of the Big Bang. It was true before, when there was just hot gas and nothing else.
Ard: I mean, if you think about it that way, it’s really hard to believe that wouldn’t be the case.
David: Except that if people, physicists, would say look, ‘I’ve got bosons and I’ve got quarks, you know, what is the particle that carries the idea?’ That’s what...
GE: Yeah, but physicists have great trouble telling you this famous question. Why does mathematics underlie physics? The famous thing that Galileo said that the nature of the universe is written in mathematics. And Wigner and Penrose and other people have pondered, why is it that physics can be written in mathematical terms? And that’s a deep philosophical question for which we don’t have a proper answer.
Ard: So the unreasonable effectiveness of mathematics?
GE: The unreasonable effectiveness of mathematics, yes.
Ard: So that kind of raises another really interesting question, because there are these abstract truths, like the truths of mathematics, the world of ideas. Where do those come from?
David: You said where this time.
Ard: This time I said where. Where do they come from? I didn’t say, ‘where are they?’ But, ‘what is their cause?’
GE: What is the cause of those mathematical logical truths?
Ard: Yes, exactly.
GE: It’s the nature of logic is all I can say. That is the way it is.
David: You see, for you, it’s God.
Ard: I think it comes from God.
GE: God? Okay, well I’m prepared to say that that is one possibility. There’s an alternative possibility, which is that God has to obey…
Ard: Obey the law of logic.
David: God is one of the ideas in your realm of ideas.
Ard: Well no, there’s a long argument among theologians and philosophers…
GE: I’m sure there’s a long argument with theologians.
Ard: …whether the laws of mathematics are created by God, or whether God, in fact, has to obey the laws of mathematics. So, for example, you might say, even God can’t make a square circle because it’s a non-logical. It’s law of non-contradiction. But the interesting point is that here we have these abstract, non-physical realities that have causal powers in our world. We think of God as a non-physical, abstract entity who has causal impact on the world, so there’s some analogy there. And once you hold that there’s one kind of non-physical reality, then it’s not so strange to think there might be another kind.
GE: That’s this kind of theology which I avoid.
Ard: You avoid theology?
GE: Yeah, I avoid theology.
GE: From my view point, existence isn’t just physical existence: there’s these abstract existences. So then you should ask me in philosophical terms how do I justify the word existence? And I’ve got a very simple answer to that. I take the existence of physical entities, like we’re seeing in this room, as being real – that’s my starting point – and I take the hierarchy of this to be real. So, in other words, this thing is made up of a metal ball, which is made up of atoms, which is made up of quarks. I believe that the ball is real, as well as the atoms are real.
I think just because it’s made of atoms doesn’t mean that it isn’t a real ball. So that physical hierarchy is real. Then I say that anything else which has a demonstrable causal effect on here must also be real.
David: Ah, so your ideas?
GE: Otherwise you have uncaused entities in the world.
David: Right.
GE: I’ve got in my hand a pair of spectacles. Now, how did they come into existence? Someone had the idea of a pair of spectacles and then created these by a machine, and so on. If they hadn’t had that idea, this wouldn’t exist. So that idea has to be real too, even though it’s not a physical entity.
The generic way to think about this, the deep structure of cosmology, is possibility spaces. Now, physicists like to talk about physical laws, but you can talk about the laws, or you can talk about what is possible given those laws. And actually, in many ways, it’s better to talk about what’s called a phase space, or a Hilbert space.
Once you start the line of argument I’ve been giving, there’s a mathematical possibility space. It’s a space of possible logical arguments and outcomes. If you now keep pursuing this line of argument, we can only think a thought because it is possible to think the thought. That sounds like a meaningless tautology, but actually what it means is the following: there is a set of possible thoughts which is up there in some Platonic space. You can’t think a thought unless it’s one of the thoughts which can be thought because it’s a logical possible thought.
David: So that realm of ideas your talking about, you would say that came into existence in the Big Bang along with… along with the…?
GE: I wouldn’t necessarily say it came into existence. I think it might in some sense pre-exist the big bang.
David: Oh, okay. Pre-exist. But it exists, so then what natural selection is doing was creating more and more complicated minds, or brains, rather, and at some point they can access this realm?
GE: That is correct, and so that space of abstract stuff was sitting there waiting to be discovered, and eventually minds reached a sufficient complexity that they could discover it. But that space doesn’t need minds to exist, it’s there.
David: It’s there already.
GE: Yeah. There’s a wonderful book out of this by Paul Churchland called Plato’s Camera.
David: Yes, I’ve read it.
GE: And Plato’s Camera talks about, in detail, how the structuring of the mind as a neural network enables us to recognise Platonic patterns, and they then get incorporated into electronic patterns in the brain, and then they can go down and effect what happens in the real world. So I see this causal link from Platonic spaces into intelligent minds, into electrons. It’s a downward causation, and then into causing effects in the real world.
For instance Pythagoras’ theorem is used by surveyors and architects. Or the number Pi is discovered, and it’s then used by engineers and it changes what happens in the real world because it’s used in engineering design.
David: So ideas have some kind of existence in our universe. It’s just it’s not a, sort of, physical existence like wood or steel.
GE: Yes, that’s right.
DavId: If you’re saying then that mathematical ideas exist in our universe in some way…
GE: In some abstract way.
David: In some abstract way, could other kinds of ideas exist in the same way? Could there be moral ideas that were there? I’m not advocating that there are, but it occurs to me if you say, well, the square root of two was always there, by what authority would you say, well, moral truths couldn’t be?
GE: Now we’re getting to interesting territory here. The fact that it is possible to think of moral thoughts is a very, very deep fact about the universe: the fact it’s possible to think that things are good and evil, bad and so on.
And then my direct answer to your question is, do I think that it could be that there is a space of moral reality? And my answer is yes. I’m a moral realist. I’ve written a book about this called On the Moral Nature of the Universe with my friend Nancy Murphy, and we defend strongly the idea of a moral reality.
Now what you have to do there is then say, well, what is the nature of the moral reality? And you then have to realise that the simplistic views of morality are not correct. Real morality is not a set of ten laws on a tablet which you can write down, because those are a terrible approximation to the real thing, and from my viewpoint, the deep nature of reality, which is discovered by the spiritual members of all the great traditions in the world, is that the deep nature of morality is to do with self-sacrifice and giving up on behalf of other people. It’s counter-intuitive. It’s not a logical argument, and people are looking for logical laws that they can apply. But the deep nature of morality, from my position, is that it is the counter-intuitive thing: that if you want to get something, and create greater good, you must give up, and the way to getting what you want is giving up what you want, and that’s the way to get what you want.
The religious literature has known this for thousands of years: the fact you feel good about something doesn’t mean that it is the good thing to do. Good and evil is not scientifically measurable and so it’s not a scientific concept.
Ard: But the point is just because you can’t measure it scientifically doesn’t mean that it’s not true.
GE: Oh, I think it’s true. As I say, I think there’s a moral reality. I believe passionately that apartheid in South Africa was an evil. I believe that the Holocaust was an evil. I think that that’s a fact, a moral fact.
Ard: And you were involved in the anti-apartheid movement. Do you want to tell us a little about that?
GE: Well that’s a whole other story.
Ard: But you passionately believed…
GE: I believed that it was morally wrong what was going on. Not that it was socially wrong or that it was politically wrong, but that it was wrong, fact.
Ard: And that motivated your anti-apartheid…
GE: Yes.
David: And the way that you are describing moral facts, you would have felt that that was a moral fact that apartheid was wrong with the same certainty and power as the square root of four is two. They are both truths.
Ard: And there are people, surely, in your social class or in your friendship groups who believe apartheid was fine?
GE: Yes, yes.
Ard: So you would say they are wrong?
GE: There certainly were people who thought in various ways it was right, and I happened to believe they’re wrong. Now it’s not a scientific thing: I cannot prove scientifically they were wrong. It’s a moral or philosophical understanding, and so if you say prove it, I can’t prove it. All I can say is it is my belief that this is the way things are.
Ard: But if you say, ‘Oh, it’s my belief, I can’t prove it’, that sounds like you’re taking a step back and saying, ‘This is my belief. Your belief is that apartheid is fine, and, you know, let’s leave it that way.’
GE: My belief is that there is an abstract moral standard.
Ard: And do you think that in the anti-apartheid movement this idea that it was wrong, and that that was a fact, played a big role for those who fought against apartheid?
GE: Oh, I think so.
Ard: People sacrificed for this?
GE: Absolutely. I mean the point about this is exactly that. I take someone like Desmond Tutu as being the classic person doing that. For him it was absolutely not the slightest question that it was an evil, and this wasn’t an opinion, but it was a fact that this was an evil.
Ard: People are often nervous about the idea there is moral truth out there.
GE: Yes.
Ard: And they’re nervous because they worry that you’ll use that to hit them over the head.
GE: What?
Ard: You’ll use that to whack them.
David: And say it must be like this.
Ard: It must be like this. And others say, ‘Well, you know, our morals can be explained on evolutionary grounds; evolution gives us morals.’ What do you make of that?
GE: There are many attempts nowadays to derive morality from science. Some are from evolutionary grounds, some are from neuroscience, and so on. They always introduce, by the back door, some concept of the good life which they take for granted without discussion, and they assume that’s the right thing. They then go on to talk about morality arriving out of evolution. So, for instance, the fact that people have behaved in a certain way does not mean it’s a good way to behave, and so a lot of people say because people did that, it’s good. People try to say because it promotes people living together, it’s good. Well, who said that people living together is good? It may be good for survival, but it’s not the same as good in an ethical sense.
Now, for instance, a book called The Moral Molecule is based on the idea that a good life is a happy life. Well, if a good life is a happy life, we can solve it by giving everybody drugs and we’ll all feel happy. And then is that a moral life? Of course it isn’t.
Ard: Can science explain morality? It’s very natural. You look around you – you see technology, how it’s changed our lives, medicine, how it’s made our lives better, healthier, in really dramatic ways, and that has come through the power of science.
GE: Yes.
Ard: And so it’s very natural to think we’re going to use those same methods and solve the perennial problems of what is the good life.
GE: Well there’s a very different question. Will science solve the problem of what a good life is? Or will it help you to live a good life once you’ve decided what it is?
Ard: Exactly.
GE: Okay, science can do the second, to some extent, although, of course, technology is only a fraction of the solution: a huge part of living the good life is to do with psychology, sociology, philosophy, ethics, and so on.
Can science tell you what a good life is? My answer is an unequivocal, no. There’s no chance science can tell you what a good life is, because there’s no scientific experiment for what is good and what is bad.
And as I’ve said already, whenever people claim they’ve got an explanation from evolutionary theory, or genetics, or neurobiology, they always import, behind the scenes, a concept of what the good life is, and they don’t tell you they’re doing it. They take it for granted, and you have to learn to challenge them when they say this is what will make you make things good, and you have to challenge them: ‘Well, how do you know it’s good?’
And they will keep on coming back to you with some assumption about what is good and what is bad, and that is what science cannot do.
Morality is a completely different dimension. Science can explain what I would call the lower reaches of morality. It can explain certain behaviours which tend to enable societies to live together. To call that good or bad, it’s simply... it’s the wrong dimension. It’s not a moral dimension.
David: I wanted to ask a related question, because it’s come up a lot. There’s the reductionist side of things. They’re also fond of saying, ‘Look, there’s no such thing as meaning; things don’t mean anything. There’s no meaning in this, no ultimate meaning in the universe.’ And I’m just wondering what you think about that?
They paint this picture saying, ‘You know, our position is meaningless, and we’re one species, on one planet, round one sun, and the laws the universe is governed by have no meaning.’
GE: The laws have no meaning. What actually is happening here is the following, and I’m seeing it with a lot of my scientific colleagues. There’s a lot of data about the universe. Basically what is happening with these guys is they’re saying if you want to understand the universe, you must take data from microscopes, telescopes, particle accelerators. You must take that scientific data, and that will tell you the nature of the universe.
When they say the universe is meaningless, the hidden agenda is they are saying, ‘We choose to ignore all of the data from human life, human history, from the great literature, the great art, all the rest of it. We choose to say that that has nothing to tell you about life and the universe, because we think the only evidence that matters is the matter that the hard science can tell you.’ They’re arriving at that position by ignoring all of the data they find inconvenient.
David: Yes. So their conclusion is already there in their assumptions about what counts as evidence.
GE: Yes. And, of course, with these people, they either live a totally bipolar life where they have these theories over there, and then they go to their family and say, ‘Hello’, and life is all meaningful, and they pat the dog and play with the child, and all the rest of this. Or they don’t, in which case their home life must be bloody hell.
I think one of the things which is a simple fact is that there is meaning in the universe. Now, where or how that meaning arises is something we discuss, but the fact that there is meaning in the universe is, I think, absolutely…
David: And it gets back to fine-tuning, because I always imagine all the universes, and I was thinking if your god had to find the universe again, it would need to have little signs by them: ‘This is the universe that’s got life in it.’ And I think the word that God would write down on the flag attached to our universe would be meaning. It’s not just fine-tuned for life, it’s got meaning in it.
GE: Well, you see, it starts off much earlier than that. All of biology is to do with function and purpose in some sense. What is that information for? That information is all for a purpose. It’s for a purpose of reproduction, of getting food, of sensing things. So life is about purpose.
David: So not only is there meaning in the universe, you’re saying there is purpose as well?
GE: There is purpose in the universe. I’m not saying it’s built into the laws of physics. It’s not built into the laws of physics, but it comes into existence, and there isn’t any question it comes into existence. How does it come into existence? Well, my position on that is that the possibility of meaning is built into some of those possibility spaces. The possibility of meaning was there before the universe came into existence, and so therefore, in a sense, the universe was expecting meaning to arrive. And I think that that is, once you start thinking about it, a logically incontrovertible position. There is meaning in the universe. That is only possible if it’s possible to have meaning, which means one of those possibility spaces I’m talking about had the possibility of meaning in it.
So the deep question, the deep question of cosmology, is why are those possibility spaces what they are? And the theological position is very persuasive in many ways for this, because the purely physical argument doesn’t begin to touch a lot of what is going on in the universe we see around us in our daily lives.
Ard: I think that’s right. You need to think theologically.
David: No! No! George is saying the opposite! I don’t need to think theologically. I don’t need God. I just need to have this realm of ideas, which is where…
Ard: But the question is, where did this realm of ideas come from? The theological explanation makes the most sense.
GE: I think you can defend with absolute certainty, as it were, once you’ve thought this through, the existence of these possibility spaces. If you ask where do they come from, you’re then in a realm of speculation where everything is right open and I…
Ard: We think a theological explanation is a good one but you don’t, yeah, as long as you… you don’t have to buy into that if you don’t feel it.
GE: If you have someone who says there is no meaning in the universe, I can only say they are just ignoring all of everyday life.
David: That’s the feeling I’ve had all along.
GE: If you want to ignore all of everyday life, that’s fine, but then don’t tell me you’ve got an adequate theory of the way the universe is because you haven’t.
David: Yeah, that’s exactly how I felt all along because it does feel like just explaining away the things which your present bit of science has a difficulty explaining, it just seems to be not…
GE: It’s one of those tricks: someone tells you what questions you’re allowed to ask and what you’re not allowed. Where do they get the authority to tell you what questions you’re allowed to ask and what you’re not allowed to ask?