In Our Time - Science in the 20th century

Episode Date: November 5, 1998

Melvyn Bragg and guests discuss how perceptions of science and the power of science have changed in the 20th century. Does scientific endeavour increasingly concern itself with doubt rather than certainty, and is it coming any closer to integrating with other disciplines - philosophy or the social sciences? How much does the scientific explanation of the world owe to a wish for coherent understanding we all have, rather than objective observation, and why are we alternately disapproving of, then obsessively over-enthusiastic about new scientific theories? How far has specialisation in the sciences obscured our view of the world in its entirety, and if scientists want to operate within a social framework, can they do so and still claim to be objective and value-free in their findings?With John Gribbin, Visiting Fellow in Astronomy, University of Sussex and consultant to New Scientist; Mary Midgley, moral philosopher and former Senior Lecturer in Philosophy, University of Newcastle.

This BBC podcast is supported by ads outside the UK. Thanks for downloading the In Our Time podcast. For more details about In Our Time and for our terms of use, please go to BBC.co.com.uk forward slash radio 4. I hope you enjoy the programme. Hello, science appears so triumphant now that increasingly it seems the supreme, unchallenged source of truth, knowledge and wisdom about life,

its origins, its processes, even its purposes or lack of purpose. Mary Midgely challenges this in her books and essay. She's a moral philosopher until her retirement in 1980, the senior lecturer in philosophy at the University of Newcastle. Her books include Evolution as Religion and Science as Salvation. I'm also joined by John Gribbin, visiting fellow of astronomy at the University of Sussex and a prolific writer of popular books on serious science.

His latest, a must in my opinion, is called almost everyone's guide to science. John Grin, you say pretty much all of science can be understood by the average man on the street and yet Richard Feynman said nobody understands quantum mechanics. So where do we go from there? Depends what you mean by understand. In the sense that people can and ought to have some knowledge

of something that's so profound and important in everyday life, there's no reason why everybody can't get a grasp of what the important parts of science are and what it's all about. Of course, to do research, you need the advanced mathematics and so on, and perhaps when you start talking about the very deep issues, then there is a level at which. understanding fails because science is an ongoing process. We don't know everything and probably we never will. So I'm really, in this book, I'm trying to address an audience that doesn't normally

have contact with science and tell them, look, it's not as scary as you might think at another level. Perhaps it is scary. You've written a great number of books almost proselytizing the science. Why do you think it's so important that the general reading public knows about science? I think it's important at two levels. I mean, one is that. One is that. that it is very important in a technological society. It's become a cliche. And if we have issues like genetic engineering, what's going to happen we just heard on the news

about people who have got genetic diseases, how they're going to be treated by insurance companies, then it's important that the voters should have an informed opinion which they can pass on to the politicians and that appropriate action is taken. So that's a very sort of practical, basic down-home level at which it's important that everyone understands science. But there's also something that I've come,

increasingly to feel very strongly about in recent years and months, is that science is a very profound way of thinking about the world. You mentioned Richard Feynman, I mean my hero, if you like. He also made this point about the way we think about things, the way scientists think about things, the importance of doubt and uncertainty and not believing things at face value. And, of course, something else that's important

is understanding things like probability, whether things are happening by chance that are, flukes or not flukes, and that helps you to have an image of the world and what's going on, which is very useful, even if you're not a scientist. Yes, and I find some, I thought the book was very good, and I enjoyed it and great, some of it is

quite difficult, and over the past few years, I've managed to read a few science book, so your idea that this is just simply set out for people. I think it's written with great lucidity, but I don't think it's as simple as all that. Perhaps this is not a criticism. Well, perhaps I'm being too optimistic, but I think you have to

perhaps be prepared to work at something and you may read it through once and find some sticky patches and I would hope that the reader might then come back and read it again and again and absorb that stuff. Can I take one of your arguments a bit further? You say in the book, everything fits together

in the modern scientific world view. The scientific world view is the greatest achievement of the human intellect. Everything fits together. That's a phrase that took my attention. Now, Everything for it. You obviously mean that, don't you?

Yes, everything in science, but I argue that science does tell you about everything that's going on in the world. Everything we know about fits together. I'm particularly using that expression because of the, there's been a kind of a backlash of people saying silly things, like that astronomers say that the universe is younger than the stars within the universe, things like that, that there are conflicts in science, people who set up these straw men, this debate between people like Stephen Jay Gould and Richard Dawkins about how, evolution works, is presented to the public as a big conflict in science. It's not. It's a very small conflict. And when you look at the whole web of the thing, everything does fit together, the

way atoms work, the way molecules like DNA works, the way the universe works. It all fits into one pattern. We don't have all the details. But you are talking, I'm just moving to a final point before I ask Mary Misley to join it. You are talking about something which is comprehensible in terms of science. And I think you're quite with approval, the remark by Einstein, that the eternal mystery of the world is its comprehensibility. Yes, I mean the fact that the two ways of looking at this, one is that in roughly 300 years from Newton and Galileo to the present day, we've gone from knowing scarcely anything about the way the world works

to knowing almost everything about it. And the other, that in the span of a single human lifetime, or about 10 years, you can go through university and learn all this stuff. And that's amazing that it is possible to comprehend in such simple terms. What's your reaction to this, Mary Magistia, this idea of the comprehensibility afforded us by science? Sorry, I do want to start by saying, John, I'm a fan of your work. I have over the years got great profit from reading your clear statements about science-specific things. I am very impressed with the way you take seriously the need to explain these things to the rest of us.

I think what you just say is dead right that we do need and can have these things explained. It is hard work for the explainer, as I well understand. also a bit of work for the reader, but it's got to be done, and I have you as a pin up on my wall for doing it. Thus, I am rather shocked by the remark and the line, which, Melvitz just mentioned, everything fits together in the modern scientific worldview. Now, every scientist I know who thinks about this kind of thing

is deeply worried about discrepancies between general relativity and quantum mechanics. I don't understand those, but I hear from a great number of people who do that they don't fit together, that they are actually in their present state incompatible. This isn't a scandal. It's the sort of thing that you would expect with any big ongoing intellectual enterprise, but you seem to me to be slurring over it. Similarly, I'm sorry, I'm going to say a couple of these things before shutting up. It is not a trifling matter.

the debate between Richard Dawkins and his selfish gene and Stephen Jay Gould and a view of evolution in which the organism is the central thing, it's an extremely important matter in everyday thought and in the science that goes with it. Again, it's not a scandal that there should be this big dialectic going on. Something's going to come out of it, but of course the idea that in the end we're aiming at a unified system is essential. but the thought that we've got it seems to be quite unreal. Third one, you start with a chapter saying, if it disagrees with experiment, it is wrong.

Laying that down, as I think Karl Popper did, as an absolute principle, you then actually quote later, Arthur Eddington, saying, if your theory disagrees with, if experiments seem to disprove your theory, that doesn't matter very much. It only matters if it conflicts with this. second law of thermodynamics without comment. Now, I know you could, you know, you could explain that what they do when there is disagree with experiment, as happens all the time, they disregard the experiment and wait and

alter the interpretation and eventually something gives. But I do think that this is so oversimple, after all the pointing out that there has been in the last 20 years of how it's not as simple as that, that it's really misleading even to your very simple reader. I think you must feel like Grenville and the revenge with all the ships turning their guns on them, John is Perthaghan. You certainly do.

I'm going to sit back in you this, John Grimmons. Well, the first one, the physicists you've been talking to about general relativity and quantum physics are out of date. I mean, there is no conflict. At one level they apply to different things and at another level

at the very exciting level that's going on at the moment theory of strings, they do fit together. And there is an immerse. picture of how quantum physics and general relativity do emerge from the same paradigm if you want to use those terms. And that's explained in another of my books, but I won't go into that. I think you ought to have mentioned it and said so. If so. Well, there's only room for so much. I have written another book about that, so to cater for that particular

interest. And I do take issue with you about the importance of the, for want to a better term, the Dawkins Gould debate. I think it's really is a storm in a tea cup and neither of them disagrees on the basics on the basics works, how evolution works, how genetics works, how natural selection works, there's just a what seems to me a mild disagreement about the pace of change and so on.

And the business about Eddington's quote, well of course I mean I succumbed as writers tend to do to a juicy quote from Eddington to emphasise how important the second law of thermodynamics is, but I do very much subscribe

to the view which I Richard Feynman very strongly subscribed to, if it disagrees the experiment, it is wrong. And of course it's very important to appreciate that we're talking here about the best scientists. There are always people who want to defend their theory to the death, that the journeymen, but the top people do try to live by those rules. Mary, can I direct our attention to something that you've said about your great worry about the reductionist tendency of science? Could you explain what you mean by that and why you have a great worry about it? Oh, sorry, you're picking on something particular that I've said.

Yes, yes. You said that you question the reductionist view of signs, that our bodies and our minds are machines and that signs can reduce the working, are working to parts that can be explained in this way. Well, reductionism, I'm sorry, I'm hesitating because reduction can mean a great many different things. The simplest kind of reductionism is the idea that you can explain the working of any hole by taking it pieces that its smallest parts will always explain what's going on in the hole.

This is often indeed linked with the machine image as though one were putting together the cogs. And since one makes the machine oneself, of course one then knows how the cogs are being put together. this has of course been a very useful way of discovering a lot about the physical working of things but the more complicated the holes get the less satisfactory it is perhaps I should pick on the example here that I've chiefly engaged in a way at the moment namely the idea of Gaia of the earth as a whole

self-regulating and self-mentary hole, that has shocked many scientists and scientifically minded people because it proceeds outwards first rather than inwards. Because in looking for the explanation of something that's going on on the earth, it looks to the whole of the earth and fits it into that larger hole. I think it is perfectly clear that explanation isn't always done by, cutting things up. If a biologist is presented with a leaf,

you see, he doesn't only does he cut it up, boil it down, put it under the microscope, he also asks on what tree, in what forest, in what climate, on what soil, in what ecosystem, this is, the leaf is growing.

And this is so taken for granted as part of the way that people normally do investigate anything that they come across that I think it is sometimes for gotten. In investigating human affairs, this is obviously still more true because the complexes that we have, the cultures and the historical situations we live in are so complicated. There is a temptation to say we have explained a human action by chopping up and boiling the brain and we now

have such very good ways of chopping up and boiling the brain and observing things that we didn't use to be able to, that there's terrific faith in this eventually producing the explanation of what's going on. I think the most distressing kind of example of this at present, I think, is a tendency to look for the course, to explain alcoholism or autism or mental illness generally by investigating the brain. Rather than looking at the situation,

I saw lately some statistic which I can't quite remember about a very high number of the people in prison, suffering from mental illness and the need therefore to diagnose them medically. Now, the first thing it seemed to me was needed there was to see what the prison was like. You know, I'm going on rather than, Melvin. I wasn't quite sure which way to start,

but I mean, you know, this is a quite general objection to only investigating things by chopping them up. It is not an objection to that kind of investigation being all right and important. It often is. But to move it on it, though, John, Would you say with Dawkins, because Dawkins's view of guy is very

indifferent from Marys, I mean, he just thinks that it, this, everything, working for everything else is a nonsense, really. Things work together for reasons of their own. But would you say that science is moving towards, and one of the things that science might do, because you're quite hesitant, is to explain everything, that everything will be explained by the analysis of the, what the particles do, the neurons do, and so on and so forth,

Do you believe that that is happening? I do believe that that is a part of it, but that you have to look at how things interact with one another. Now, whether you're talking about cells in the body or the living part of the guy. But are you talking about physical interactions? Yes. Because Mary's talking about something else, you see.

No, I mean, I think one of the really interesting things that's happening at the moment is the study of what's called complexity, how lots of simple things working together produce complex systems. But I think that can be understood in terms of simple physical rules. they're slightly less simple than the ones we've been used to. And since Newton, we've worked our way down, if you like, and worked out all the basics. Now we can work upwards with that knowledge of the basics

and see how complex things work. But I don't think you need anything new. And I agree that there are more than one factor involved in many things. There's a debate that I'm involved with about climate change and global warming. And there are people who say, well, it's not just carbon dioxide. They say it's not carbon dioxide at all. It's caused by the sun or by volcano.

or whatever. And of course there's a bit of truth in all of that. There's more than one factor involved. And what you do find is that people proselytize for their own view of the world and say it's all so and so. And it's not. It's complicated. And Gaia, I'm fascinated by Gaia. I think it's a really wonderful paradigm that's enabling people to think about the planet in different ways. But then you're not talking about each component acting for the good of the whole. Each component acts for the good of that component in feedback with all the other components and that's what produces the interesting complexity.

But you're still talking about things being explained through things and as I understand it, Mary, you say there are other explanations. One of the things you say is that the trouble with science is not that it tells unwelcome truths, but that its prestige obscures other truths which are every bit as well established and important. Could you develop that? Yes.

I mean, speaking with people and animals, for the moment. If you want to explain somebody's action, it seems to me that the question that you're asking is often a question in terms of motives and in terms of beliefs. Why somebody suddenly abandoned his job and went off to live alone in a hut.

And I'm deliberately making a rather obscure one. It may be true, And I don't wish tonight that somebody who chopped up his brain or investigated his brain would find some kind of mechanical procedures. And possibly would be able to generalise, say, these mechanical procedures are found in people who do that kind of thing. But this would not explain in the sense that it's wanted. The kind of explanation that's wanted for that sort of action is an understanding of it, which is a sort of sympathetic understanding. I mean, when we feel we know why somebody did something, we ourselves feel an analogue of the feeling that they felt.

If we can't do that, we say, I still don't understand it, even though I dare say it was physically caused. We need that all the time when we are interacting, even in the most automatic and boring things like buying newspapers. I mean, the trouble with poor autistic people is they apparently haven't this sense, of how it is that other people are feeling that the sort of motives that they have. So for them, other people are a constant puzzle

because the kind of understanding that's needed isn't there. Now, it seems to me no insult to science to say. It's not the business of science to provide that. History ought to be done with that in mind. When people give historical explanations of why people have acted, they should provide explanations which are open to that sort of, that sort of inwardness from the person holding them.

I don't think this is superstitious or fishy, John, if you think it is to say so. I'm allowing you see that this in a way may go parallel to some physical explanation, which in principle might be got. But of course, the physical explanation is always much harder to get, and it's not really on the card. you're going to get universal laws for it because people don't... Sorry, can I just want to bring John in on this point? We're going a long way down here, which is fine.

You did ask me. I want you to come into... Sure, I think I would say that all those things are within the province of science and that science can hope to understand them, not necessarily in terms of specifically why a particular individual will make a particular decision at a particular time, but in terms of how the brain arrives at those kinds of decisions, how complicated networks work, which is where a lot of works being done now.

And you have situations where a very small change in one part of a network will send a sweeping change right through the whole network. So a small trigger can profoundly change something as simple as a pile of sand on a table or the decision that you make. But you're still coming in with this mechanical explanation, which I think is very interesting. Answer to a different question. Mary has said something else in one of our sides, which has said the whole world contains electrons and elections,

toothaches, money and dreams, and they can all be explained, but the explanations are various. Now, what do you make of that, John, this phrase, the explanations are various? It struck me as a very good phrase, and it was telling, but if they're various,

what other explanations can you imagine beside the explanations which you attribute to science? I can't. My imagination perhaps is failing, but I don't see any problem. I don't see any problem at all in explaining, in principle,

in explaining everything in terms of science. Bearing in mind, you have to use statistics. One second. So why people sort of fall in love? love. That can be explained to them. Why people get obsessed by someone they're in love with, that can be so. I'd be entirely happy with that. You're entirely happy?

It's a causal explanation. Why people imagine plays, white people, this is all, there's no other, so outside our skulls, as it were, everything, when we will eventually probe the brain, and that will eventually tell us about everything including being able to imagine

billions of miles across the unit, and that will all be explained. I think so. So Einstein, the eternal mystery the comprehensibility, we will comprehend mysteries. Well, we may not ever get that far. It's a big subject. And there is the, when you get to a certain level of complexity, it's very difficult to understand it without having something bigger.

Because I think what Mary is saying is that there is this physical, I don't know what I'm going to talk to Mary immediately. I am not talking Mary immediately. I can't say, like, all the tape goes back. We're not alive. Yes, sir, I'm like. Is that this is the brain, and that's fine. But there is also the mind as far as I can.

And the mind actually is, you know, as consciousness. knows things that we don't know the brain can know. Now, does that... Well, yes, because it's a different sort of question that arises. Can I give you a very simple example, John, football game going on? Somebody who doesn't understand football is standing watching, says, why has he been sent off? Now, the explanation of that has to be the rules of football.

And what you... You see? This is social. This is a social pattern that is being asked for. And until you had that social pattern, the story about what's happened inside their heads isn't ever going to make that sense. You know, you can't explain football. There are straightforward reasons. Yes, you can.

You can explain why we have games as a substitute for warfare, why people are aggressive, why someone does kick somebody in the head and get sent off. This is causal. You are not telling the person about football until they know the rules of football. None of that's any good. And most of human life consists of conventions of that. kind. If you don't know the conventions, you aren't going to be able to act suitably. The motives

have indeed the physical side and I honestly am not saying that there's anything fishy about the way the stuff works or that there's an extra soul there, you know, anything of that kind. It's just that a different kind of question is being asked. Melvin seems to see this. Yes, I do. Well, can we develop

those different sign of questions and see if John take, is it a religious question that's being asked? And if so, where does that religious question comes from? About football? No, about the various explanations, the various questions. You mean, why are we asking this question now? Because we have a confused belief system. But why do we have a confused belief system?

Oh, because it's quite difficult to get clear ideas about the world. I mean, you see, the... But John would say that's because we haven't actually tapped into quite enough knowledge about the neurons and everything else, whizzing around inside, trying to make sense of this morning's programme. Look, John, it appears that it's only physical. Physical science and not social science that you're putting forward to do this job, is it? You're not just saying psychologists by making better experiments could understand it better.

You're really saying that it's the movements in the brain that are going to be the only explanation? Yes, of course. I don't see how there's nothing else in the world except in our perceptions. There's nothing else in our perceived world except movements in the brain, electrons moving about and so on. This is something which, in fact, we very rarely perceive. I mean, what's in our ordinary perceived world is things like money and table, and clocks and food and apples, much larger objects, and the ways in which they interact are what we need to know about

and the ways in which the whole person interact, if you didn't know that, if you were, you see, an alien scientist, an alien scientist sitting in a lab, who's been shown all these physical details, they are conveyed to him, about what's happening inside our heads, but who does not understand the social conventions by which people are moving or what it feels like to be them, you would understand, okay, you'd go on understanding the connection between the neurons,

but this is never going to tell you what football is or what money is or why somebody does something, because that all takes place on a quite different scale. And it's not any different causal item that's being put in, but it's that the relations between things at the macro scale are themselves of a different kind. It's quite difficult to catch your. You tend to think whether I should manage.

It's perfectly all right. Yes. I'm trying in no end. I'm just trying to go to an old morning. I'm just trying to say, let John get in. Sorry, yes, carry on. No, I think I come back to the analogy that the complexity people use, the pile of sand.

You can understand the physics of a grain of sand and the friction and how it rubs against another grain of sand. And if you just make a big pile on the table and keep dropping sand on it, it piles up to a level where it makes a certain critical angle, and then you get avalanches and you get pretty patterns, and it stays at that angle, but it's the same laws of physics, just because it's a big pile with a pretty pattern.

And is it the laws that, Mary's on to something very important. Nobody denies that. You're still not addressing her main point, John. We've only got a couple of minutes. Just answer the problem of the world in two minutes, you'll be saying. But the thing is, why do we have consciousness of what we're doing? Why do we have what seems to be...

That's all there is to it. You've got a lot of neurons stuck together, and bingo you get consciousness, and it'll happen when you put together electronic computers to that level, or whatever you do. You think artificial intelligence will eventually have consciousness? Absolutely, yes.

And soon, within 50 years. This isn't quite the point. It's explanation now, you know. As you go around today, you'll want a lot of things explained, and you'll explain them in terms of the interaction of moderate-sized things like us. You won't find that an incomplete explanation unless, if you want more about why somebody did something, you'll want more about what it feels like and the like.

when you give the physical explanation of what's happening in the neurons, that's something coming in from a quite different angle. I've given, can I list this moment, the analogy of a great big, what you call those things with water in and fish? Aquarium. I'm sorry, yes, which you're looking in at, you see through a lot of different holes and different corners.

You're looking through one hole, and you're seeing this about the inside of the head. You look in from a hole on the other side and you see the fish actually moving about. Now, that's something which is not substituted by the details. There's a lot more we need to know, but we're getting there, and it will all add up to make a coherent picture, I'm sure. Good luck to you.

We didn't, yeah. We've got another 20 seconds. The way we're going, we could actually sort of revolutionised physically in the other 20 seconds. Okay, well, thank you both very much for that yellow. John Gribbin's book is called Almost Everyone's Guide to Science, The Universe, Life and Everything. That's just been published. Mary Midgely is speaking at a conference for Gaia at the Linnaean Society in London. That's part of the Royal Academy at London this evening.

Thanks both very much indeed. We hope you've enjoyed this Radio 4 podcast. You can find hundreds of other programmes about history, science and philosophy at BBC.com.com.