David: Can you tell us what it is you do? Because I know you do quite a number of things.
SG: Well, in the sciences, I’m interested in understanding how diversity emerges in infectious disease systems.
David: You’re not just a scientist though, are you?
SG: No, I write novels as well.
David: And how do those two things sit together in one brain?
SG: This is a question I’ve been asked a lot, and to me they come from very much the same source, which is a desire to understand or come to terms with the world, the universe.
David: So they’re not different kinds of thinking for you? Because people often imagine that scientific thinking is very different to a more literary or artistic thinking.
SG: At one level I think they are the same kind of thinking in that they’re driven by the same sort of desire to make sense of the internal and external universe that I happen to inhabit. But the languages employed are very different, I think.
In science, much of my pleasure in using words is that they adhere very closely to whatever concept I need them to represent. So I’m always seeking there to reduce the distance between the word and what it represents.
David: A sort of exactness?
SG: Yes. So you want them to… When I write, if I’m writing an equation and I use a symbol ‘x’, I really want its meaning to be precise. I feel like I’ve failed if ‘x’ means too many different things. So the closer ‘x’ is to what I want it to represent, the happier I am. Whereas when I’m writing fiction, I like there to be a gap between the word and what it refers to. I think a lot of the energy of fiction lies in that gap.
David: A sort of ambiguity?
SG: It’s a sort of disorder that’s not an arbitrary disorder. It’s somewhere… It’s moving away from order, but not so far as to be so ambiguous.
Ard: In science people often think that it’s all about cold hard facts and there’s no imagination. And then, obviously, writing novels is about imagination. What do you think about that dichotomy?
SG: Well, I think science is all about imagination. And what attracts me to science is the ability, or the opportunity, to be imaginative. So, for me, my journey through science has been one of using my imagination to come up with different ideas.
David: Is there a narrative in science? Does science use narrative, or is that purely…?
SG: I think narrative is a very strong element in science. I think…
David: Really?
SG: To me, narrative is where we’re headed.
David: That’s not obvious to a lot of people. I think in the popularisation of science, it’s a great big museum of facts. There’s a drawer with a fact here and then a drawer with another fact there, and he who had the largest number of drawers with facts in is the best! For you, it’s not like that? I mean, what’s the role…
SG: For me, it’s not like that.
David: …of narrative in science, then? I mean, how does it…?
SG: Because I’m interested in coming up with theories – I am a theoretical biologist at the end of the day – so theories are, of course, stories. So, for me, it’s not very interesting to just have a pile of facts.
There’s a huge synergy between actually arriving at the right narrative structure and the process of science as I experience it, which is recruiting these facts and then trying to think of a way in which they fit together that is coherent.
Ard: So sometimes the scientific facts fit together to tell a story, and the same is happening when you’re writing a novel?
SG: I don’t actually like the word story, myself. I think narrative is a better term.
Ard: Narrative. A real narrative. So would you say that what makes a scientific theory or narrative a good one, is that it’s fruitful? That it somehow goes on its own and does something that you didn’t even think it was going to do when you put it together?
SG: I’ve been searching for a long time for what does make a good narrative because it’s the same in fiction. At some point the book has, for me anyway, the right narrative.
David: It’s interesting what you said, though, because I’ve spent my professional life talking to scientists, and most often scientists will say, ‘In science, you should just stick to the facts.’
How often have you heard that from a scientist? ‘In science, we stick to the facts.’ Which would suggest that if I know these three facts, then I should only talk about them. I shouldn’t generate a story that suggests it might go somewhere, to use your phrase. And yet that is the strength of a theory, isn’t it? That it points to where you might go next?
SG: It points beyond facts. Exactly. I can’t think of any piece of science that’s been done that doesn’t take the facts and then construct from those facts something greater than the sum of the facts. But I was thinking in terms of it being fruitful.
David: What was it? Use and…
Ard: Usefulness and fruitfulness.
David: Tell me the difference.
SG: So, usefulness, I suppose… You know, many models, particularly in physics, have been ridiculously useful. And their validation in some ways is contained within their usefulness. The fact that they can send us to the moon is pretty useful. But then there are also fruitful theories. Fruitful, I think, is better than that. It’s not just useful: it’s creating a universe that will allow us to move forward.
Ard: I think fruitfulness is a hard thing to explain to an outsider, but you know it when you see it. A fruitful theory is something that explains something about the world that you see, so it’s important that it links to truth. But it also often tells you things that you didn’t know before, and then those things end up also being found in nature. And then it’s fruitful: it told you something you didn’t expect.
SG: It offers insights.
Ard: Insights, and often unexpected ones: ones that you wouldn’t have ever come up with had you not written the theory down.
David: What makes something beautiful?
SG: What makes something beautiful is actually quite ineluctable. It is a feeling. It is something that I feel on encountering beauty. But, of course, there’s a whole range of this feeling which is why people have tried to separate beauty from the sublime, or from the picturesque. So there is the merely pretty as opposed to the beauty that actually approaches terror. One of my favourite poets is… well, one of my favourite pieces of poetry is The Duino Elegies and I’ve been rereading them recently. And the connection between beauty and terror is, I think, why they mean so much to me. Because he talks about beauty as terror… just about bearable.
David: He says ‘every angel is terrifying’.
SG: Every angel is terrifying. And beauty is terror that we are only just able to bear. And that’s the kind of beauty I experience when I’m looking at doing science or when I’m writing a novel. That’s the beauty that I really crave. There’s also other kinds of beauty, like in gardening, or…
David: But what makes a beauty terrifying for you?
SG: So, I’ve been thinking about that a little bit, and I think it’s that sense of approaching a truth – and I’m using the word ‘truth’ here a little bit loosely right now – approaching a realisation that will disperse something in me, that will unsettle me.
David: Change you?
SG: Change me, yes. And this notion of coming... I think it’s the terror that Rilke was talking about. The idea, the fact, the comprehension that we are in fact capable of having these huge realisations, ones that actually overwhelm us and make us feel that we are understanding something that we perhaps shouldn’t understand, that we shouldn’t go there. This idea of ‘where angels fear to tread’, I think that’s where the terror lies. And you come close to it when you understand something in mathematics, which, I mean, I haven’t been doing physics or mathematics for a very long time, but I do remember that feeling of beauty and the edge of terror.
David: Is it a sense that you’re approaching a truth which is bigger than you are…?
SG: So vast.
David: …and older than you are?
SG: Yes.
David: Because so many metaphors of understanding are to do with the hand ‒ like ‘I’ve grasped that’, or ‘I shall hammer this into shape’. And then there’s another kind of knowledge where you… it’s that word: ‘understanding’. You just stand under it, like you stand under the nave of a cathedral, and you can glimpse up and get a sense of the shape. But you know it’s vaster than you, and much older.
SG: Yes. Yes, that’s it.
David: Have you had that feeling in your work sometimes?
Ard: I’ve never thought about it that way, but I think I have, now that you mention it. It’s something about that truth being so beautiful and pure, and you sometimes feel almost impure before it. It’s a strange kind of thing. Terrifying is interesting. I never thought about it that way.
SG: And maybe, actually, when we do encounter these truths, what we experience is both: both the sense of standing near that precipice, or in that cathedral, but also something of the ‘I have grasped it’. So part of us is probably also experiencing a satisfaction of grasping it, and then the rest of us is edging towards that precipice.
David: One of the things I found fascinating when we were talking about the sense of a truth bigger than we are, and was there already, so older, is that it’s so close to how people describe encounters with the religious ‒ that you’re in the presence of a power that’s older than you are and greater than you are, that knows things that you don’t and was there before you. So it has all of the same qualities, and I wonder if that’s why for scientists who several centuries ago were Christian, they fit together, because it’s the same encounter with something older, bigger, more powerful. Does that…?
Ard: Yes, that’s interesting.
SG: I think it’s the religious sentiment.
David: In science?
SG: In science. But the religious sentiment is, to me, what’s interesting about religion. Because it does have…
Ard: This kind of transcendence.
David: And so there’s the possibility of having that same set of experiences which the religious person would have…
SG: Yes, I think so.
David: For them, they would speak about approaching God, but for the scientist, they’d say approaching a truth. But it’s the same; it would feel the same.
SG: The same sentiment.
David: It would be the same inside experience.
Ard: Or related.
David: Or related.
Ard: Yes.
David: Does that work for you? Because Ard is religious and I’m not. (I’m just making this up.) Is that possible from where you sit, or does it just sound like flowery language?
Ard: No, I hadn’t really thought about it quite like that before. But I do think when you discover something… So, there are quite a few scientists who are religious, and they’ll typically say, ‘Well, my experience of discovering something scientific is not that different from my religious experience. It’s something… I’m finding, something that’s bigger than me that I’m touching.’ And for them, and for people like myself, it points towards our religious sense. It points towards God.
Ard: I wanted to ask you something else. You wrote, ‘We have a compelling need to lend form to the universe without destroying its mystery.’ Do you think we can destroy its mystery by science?
SG: No. I think that science only… well, again we’re talking about that religious… I think we’re talking about the same thing: that sentiment of wonder, and awe, and terror. And I think, for me, one of the greatest moments of making peace with science was to realise that rather than taking away the mystery, it added to the mystery, only in the sense of that experience.
I’m calling mystery the sense of that experience, not a lack of clarity about what’s going on. But when you understand something, in all its clarity, that adds to the experience. Maybe I shouldn’t call it mystery.
Ard: No, I think that people sort of think that mystery is only about things we don’t understand. In fact, religious people sometimes think that in order for them to have God in science, they have to have bits they don’t understand, but I think that’s just the wrong way of thinking about it.
I think part of what makes science so beautiful, or that sense of the beauty of science being close to the sense of terror, is that you do see something more clearly and it’s very beautiful, but it seems to point to something beyond itself, and that’s what generates that sense of being at a precipice, where you think it’s beautiful, but it’s also actually making the mystery more. There’s more of a mystery rather than less of a mystery, even though…
SG: It intensifies the mystery.
Ard: It intensifies the mystery, even though you understand it better. And that sounds a bit fluffy, but…
David: No! Surely not, Ard!
Ard: I was accusing him of being fluffy.
David: All the time!
Ard: But I think if as a scientist you have that experience, and you do understand something, actually it intensifies the mystery.
David: Why did you say ‘I made peace with science’? When did you have to make peace with it? What do you mean?
SG: Well, I suppose… I don't know. I never thought I’d say that, but…
David: Well, you did.
SG: .You made me say it; or it came out. So what does that mean? Maybe at some point I was a bit suspicious of science. I thought, maybe, it would take away from my appreciation of the universe.
David: The sort of picking-the-butterfly-apart effect.
SG: Yes, exactly. So while I was fascinated by what I was learning, perhaps part of me feared that once it was all explained, it would get rather dull.
So it was hugely reassuring to me that when I understood something, that it actually created in me the same sentiments, the same emotions emerged as when I didn’t fully understand something and simply wanted to take delight in it.
It gave me a better understanding of what mystery – which I think is a very basic emotion, almost – was actually all about. So that must be why I said ‘I made peace with science.’
David: Is mystery aligned with meaning? With thinking this means something? That it makes sense of it?
SG: Well I suppose what I think we’re both trying to say is that there is no contradiction between making sense of it… between finding meaning and preserving mystery.
Ard: It reminds me of a quote by Henri Poincaré, a very famous French mathematical physicist, who says, ‘A scientist does not just only study science because it’s useful; he studies it because it’s beautiful. And if nature were not beautiful, it would not be worth studying, and life would not be worth living.’
It’s very French. But I think there’s something about ‘you study it because it’s beautiful’. And if it weren’t beautiful it wouldn’t be worth doing.
David: Yes. And you’ve already defined beauty as being, at least in part, that sense of it pointing forwards, beyond itself, as you would say. So that when we say nature has to be beautiful, and if it wasn’t I wouldn’t study it, it’s another way of saying, if it wasn’t always expanding, pointing to new things that it might generate. Because I think, sometimes, and maybe it’s us in the media, the popularisers, we give this impression that there’s a big mystery. But don’t worry, there’s an army of people in white coats who are clearing up the mystery, like clearing up the knick-knacks in a room. And before you know it, it’ll all be squared away like a Prussian dining room and…
SG: That’s a particular aspect of science, and what scientists do, practitioners of science do. But then there is also the exhilarating part of understanding the universe, which, for me, is what drew me to science.
David: A friend of mine’s a mathematician, Greg Chaitin. He described, I think, what you’re talking about. He said, for him, he would have small ideas: just a small idea, like sitting on your chair. Then, he said, he had certain huge ideas, and for him it was like climbing up a mountain. And the exciting thing was not just getting to the top of the mountain, but from there he could see a whole range of mountains out in the distance, which he hadn’t been to, obviously, but suddenly he realised they were there. Is that the same sort of thing?
SG: Yes. For me that’s definitely how it works. A lot of my work is built on an idea and a model that I came up with 20 years ago. And I remember that moment of watching it do something I didn’t expect it to do, which is on a computer screen. I’d written down some simple equations, and I expected it to behave in a particular way, and it didn’t. And it showed me something that then became the basis of pretty much what I do in science.
David: How did it feel?
SG: It felt amazing! It really did. And this was in the day when you could actually watch the computer simulation happening, because computers were very slow 20 years ago, and so I did actually watch this simulation.
David: So what were you actually seeing? I’m just fascinated.
SG: I wanted to see how populations of pathogens would evolve under selection from host immunity: by host, I mean us. So when a malaria parasite enters my body, I will, of course, mount immune responses to this parasite. So parasite populations evolve under this selection pressure. What’s interesting about a lot of parasite populations is that they seem to exist as these, sort of, discrete tribes ‒ different strains ‒ and this is the mystery, because there’s no reason why they should be doing that.
And what this model showed me is how, under selection pressure from host immunity, these populations would self-organise into these discrete tribes, simply in order to avoid competing with each other.
David: And nobody knew that before?
SG: Nobody had done that before.
David: And it’s not what you were expecting?
SG: No, it wasn’t. I thought they’d be a big mush, and that we’d have to think of ways in which we’d have to impose structure. So, at a fundamental level, I was setting something up where I expected there to be huge mush, and then we’d have to come up with ways to impose structure, and instead the structure emerged on its own. So that was fun; that was great.
Ard: That’s amazing.
SG: It was quite a moment.
Ard: It must have been amazing to see.
SG: It was. And so what I’ve been doing since then is trying to validate that. So I’m interested, obviously, in whether this is truth, in the sense of being a useful metaphor, or a useful framework for understanding what happens in infectious diseases, because it does have practical implications.
So that’s what I’ve been doing for the last 20 years: trying to validate that theory.