Outgrowing God

by Richard Dawkins

  Same thing if you were to jump out of a plane, sitting on a weighing machine. Both you and the weighing machine would fall at the same rate. So again, you wouldn’t press down on the weighing machine and it would report your weight as zero. Your weight is zero while you fall. But your mass remains, in full.

  That gives you the clue as to why cannonballs (and men and weighing machines) float around weightless in the space station. Many people think it’s because they are a long way from Earth and therefore beyond the pull of Earth’s gravity. That is utterly wrong. It’s a very common mistake. Actually, the pull of Earth’s gravity is nearly as strong in the space station as it is at sea level, because the space station is not so very far away. The reason objects in the space station are weightless is that, like the person who has jumped out of a plane sitting on the weighing machine, they are continuously falling. Falling, in this case, around the Earth. The moon, too, is continuously falling around the Earth. The moon is weightless, although it has a mass of 10 thousand billion billion kilograms.

  ‘The moon is weightless and continuously falling around the Earth?’

  You cannot be serious! But it’s true.

  We think of our planet as all rough and wrinkly, pitted and studded with valleys and mountain ranges. After all, Mount Everest is nearly 9 kilometres high and the first two men to climb it were hailed as heroes for their feat. But if you were to shrink the Earth to the size of a ping-pong ball, the surface would feel smooth all over. Even Everest wouldn’t register to the touch: it would be as small as a grain of sand on the finest sandpaper.

  You cannot be serious! But it’s true.

  Work it out for yourself. Measure a ping-pong ball; you know the height of Everest; look up the diameter of Earth and do the sum.

  Why are planets round? Gravity pulls them inwards from all directions. Even solid ground behaves like a liquid, given enough time. Smaller objects like comets are not round but knobbly and misshapen. This is because their gravity is too weak to pull them into shape. Pluto is big enough to be spherical. However, it is smaller than several known ‘planetesimals’, which is why Pluto has been demoted from planetary status. This upset a lot of people. But it is only a matter of definition: a matter of ‘semantics’. Mars, being smaller than Earth, has weaker gravity, and so less force to pull its mountains inwards. This is why Mars can (and does) have higher mountains than Everest. Mars as a ping-pong ball would feel infinitesimally rougher to the touch than Earth. But its tiny moons Phobos and Deimos are positively knobbly by comparison. They look like potatoes.

  Once upon a time, it seemed obvious common sense that the world stood still and the sun, moon and stars revolved around it. What could be more natural? The ground you stand on feels rock steady. The sun moves across the sky from east to west daily, and so do the stars if you have the patience to note their changing positions. The Greek mathematician Aristarchus (c.310–230 BC) seems to have been the first to realize that the Earth orbits the sun. It’s the Earth’s spinning that makes it look as though the sun travels across the sky. This daring truth was forgotten for centuries until it was rediscovered by Nicolaus Copernicus in Poland (1473–1543). So contrary was it to common sense that Galileo was threatened with torture for promoting it.

  You cannot be serious, Galileo! And we are going to torture you unless you recant.

  If you look at a map of the world, you’ll notice that the west coast of Africa and the east coast of South America look as though they might fit each other like jigsaw pieces. In 1912 a German scientist called Alfred Wegener had the courage to take this observation seriously and see where it led. He proposed that the map of the world changes. In a big way. Africa and South America, he suggested, really were once joined. He was ridiculed in his own lifetime. How could anything so massive as a continent split down the middle and the two halves – South America and Africa – drift thousands of miles apart? Yet that is what happened.

  You cannot be serious! But it’s true.

  Wegener was right. Sort of. Until about 130 million years ago, Africa and South America really were joined. Then they were slowly wrenched apart. There was a time when you could jump across the narrowest gap. A bit later you could swim across. Now the journey takes hours, even in a fast airliner. Wegener got the details a bit wrong. The evidence is now overwhelming that the entire surface of the Earth consists of interlocking and overlapping ‘plates’. Like armour plates. They’re called ‘tectonic plates’ and they move, but much too slowly for us to notice in our short lifetimes. Their movement has been compared to the rate at which fingernails grow. It’s not smooth, however, like the growth of fingernails. More jerky, with no perceptible movement for a while, then a sudden movement like an earthquake. Indeed, it often is an earthquake.

  Tectonic plates don’t just consist of land. Much of each plate is under the sea. The continents are just the highlands riding on top of the plates. It’s the plates that move, carrying the continents on top of them. There are no gaps between the plates. Where they push against each other, various things can happen. Including earthquakes. The two plates may slide past each other (that’s what’s happening at the famously earthquake-ridden San Andreas fault in western North America). Or one may slide under the other. This ‘subduction’ can push up a great mountain range like the Andes. Or the Himalayas, which were raised when the plate carrying India, then a huge island travelling north, forced its way under the Asian plate. The evidence for plate tectonics is fascinating and totally convincing. But I won’t go into it here, because I did so in The Magic of Reality. I’ll just point out that it’s highly surprising and violently opposed to common sense.

  Now for something so surprising it’s actually frightening. At least, I think it is. You, and the chair you sit on (the table you eat off, the solid rock you stubbed your toe on) consist almost entirely of empty space.

  You cannot be serious! But it’s true.

  All matter consists of atoms, and every atom consists of a tiny nucleus orbited (for want of a better word, although it’s a bit misleading) by a cloud of far tinier electrons. Between them – nothing but empty space. Diamonds are proverbially hard. As we saw in Chapter 9, a diamond is a crystal lattice made of precisely spaced carbon atoms. If you imagine a carbon nucleus swollen to the size of a tennis ball, the nearest neighbour tennis ball in a diamond lattice would be 2 kilometres away. And the space between them would be empty because electrons are too small to matter. If you could shrink yourself to a scale where you could hit one of those balls with your tiny racquet, the next nearest tennis balls in the lattice would be much too far away for you to see.

  My colleague Steve Grand, in his book Creation, wrote:

  Think of an experience from your childhood. Something you remember clearly, something you can see, feel, maybe even smell, as if you were really there. After all, you really were there at the time, weren’t you? How else would you remember it? But here is the bombshell: you weren’t there. Not a single atom that is in your body today was there when that event took place…

  You cannot be serious! But it’s true.

  Matter flows from place to place and momentarily comes together to be you. Whatever you are, therefore, you are not the stuff of which you are made. If that doesn’t make the hair stand up on the back of your neck, read it again until it does, because it is important.

  Does that mean that a man who has just been arrested for a crime he committed 30 years ago cannot be guilty because he’s no longer the same person? What would you say if you were on a jury and the defence lawyer made that argument?

  Here’s something else that’s pretty alarming. It follows from Albert Einstein’s Special Theory of Relativity. If you set off in a spaceship at nearly the speed of light, and came back after your onboard calendar told you you’d been away 12 months, you would have aged only one year while all your friends back on Earth had died of old age. The world would be hundreds of years older, but you would be only
one year older. Time itself on the spaceship, including all clocks and calendars on board, as well as the ageing process, would slow down as far as people on Earth were concerned. But not as far as everyone in the spaceship was concerned. On board the spaceship, everything would seem completely normal. So, back on Earth, your own great-great-grandson could be older than you, with a long white beard.

  You cannot be serious! But it’s true.

  The message of this chapter is that science regularly upsets common sense. It serves up surprises which can be perplexing or even shocking; and we need a kind of courage to follow reason where it leads, even if where it leads is very surprising indeed. The truth can be more than surprising, it can even be frightening. I myself find the sheer weirdness of quantum theory positively frightening. Yet it must in some sense be true, because experiments have verified the mathematical predictions of quantum theory to an accuracy equivalent to predicting the width of North America to within one hairsbreadth.

  What is the ‘weirdness’ that I’m talking about? There’s no space here to go into all the shatteringly strange experimental results. I will just mention the so-called ‘Copenhagen Interpretation’ of some of these weird experimental results. The Copenhagen Interpretation says that some events, quantum events, haven’t happened until somebody looks to see whether they have happened. It sounds daft, and the idea was satirized by the Austrian physicist Erwin Schrödinger, one of quantum theory’s founding fathers. Schrödinger imagined a cat shut up in a box in which there is a killing mechanism triggered by the kind of event which is called a quantum event. Until we open the box, we don’t know whether the cat is dead or not. But surely it must definitely be either alive or dead? Mustn’t it? Not according to the Copenhagen Interpretation. According to the Copenhagen Interpretation, as satirized by Schrödinger, the cat is neither alive nor dead until we open the box to have a look. Obviously absurd, and that was Schrödinger’s point. Yet, however absurd, it seems to follow from the Copenhagen Interpretation. And the Copenhagen Interpretation is favoured by many distinguished physicists. Somebody just sent me a lovely cartoon. The scene is a veterinary waiting room with pet owners patiently waiting. The nurse comes out and speaks to one of the gentlemen: ‘About your cat, Mr Schrödinger. I have some good news and some bad news.’ Now that’s witty.

  The apparent absurdity of the Copenhagen Interpretation has driven other physicists to an alternative interpretation called the Many Worlds Interpretation of quantum theory (not to be confused – though it often is – with the Multiverse Theory, which I’ll come on to in a moment). According to the Many Worlds Interpretation, the world is continuously splitting into trillions of alternative worlds. In some of those worlds the cat is already dead. In other worlds the cat is alive. In some of those worlds I am already dead. In other worlds (necessarily including the world in which I am typing these words) I am still alive. In yet other worlds (not many) I have a green moustache. The Many Worlds Interpretation seems in one way less absurd than the Copenhagen Interpretation. In another way more so. Don’t worry if you are totally bewildered by this paragraph and the previous one. So am I. That is precisely the point I am making. Scientific truth is frightening and we need courage to face up to it.

  In an earlier century, Galileo’s persecutors were frightened by the heretical idea that the Earth spins, and moves around the sun. Anyone might be frightened when they first discover that they and the solid earth they stand on are almost entirely empty space. But that doesn’t stop it being true. And far more often than it is bewildering or frightening, scientific truth is wonderful, beautiful. You need courage to face the frightening, bewildering conclusions of science; and with the courage comes the opportunity to experience all that wonder and beauty. The courage to cut yourself adrift from comforting, tame apparent certainties and embrace the wild truth. Like my friend Julia did when she lost her Christian faith.

  Julia Sweeney is an American comedian and actor. She wrote and performed a charmingly comic stage show called Letting Go of God. Julia was a good Catholic girl. When she grew up she started to question her faith. She thought hard and long about it. Lots of things didn’t make sense. Many aspects of her religion seemed bad to her, rather than good as she had been taught. She read books on science and books on atheism. Then one day, when her habit of questioning had reached an advanced stage, she heard a little voice in her head. At first it was no more than a whisper: ‘There is no God.’ It grew louder: ‘There is no God.’ Finally, a panicked heart cry: ‘OH MY GOD, THERE IS NO GOD!’

  I sat down and thought, ‘Okay. I admit it. I do not believe there is enough evidence to continue to believe in God. The world behaves exactly as you would expect it would, if there were no supreme being, no supreme consciousness, and no supernatural.

  And my best judgment tells me that it’s much more likely that we invented God than that God invented us. And I shuddered. I felt I was slipping off the raft…

  But then I thought, ‘But I don’t know how to not believe in God. I don’t know how you do it. How do you get up, how do you get through the day?’ I felt unbalanced. I thought, ‘Okay, calm down. Let’s just try on the not-believing-in-God glasses for a moment, just for a second. Just put on the no-God glasses and take a quick look around and then immediately throw them off.’ And I put them on and I looked around.

  I’m embarrassed to report that I initially felt dizzy. I actually had the thought, ‘Well, how does the Earth stay up in the sky? You mean, we’re just hurtling through space? That’s so vulnerable!’ I wanted to run out and catch the Earth as it fell out of space into my hands.

  And then I remembered, ‘Oh yeah, gravity and angular momentum is gonna keep us revolving around the sun for probably a long, long time.’

  Julia bravely followed evidence and reason, even though this led her out of her childhood comfort zone. This chapter is about the steps of courage that you need to take on the road to atheism. A pretty big step concerns the origin of the entire universe. We’ll come to that later. But, as I said in my introduction to this chapter, an even bigger step was to understand the evolution of life. And that’s a step humanity has already taken. We should take courage from that.

  I’ve often wondered why it took until the middle of the nineteenth century for humanity – in the shape of Charles Darwin – to tumble to the full truth of evolution. Evolution by natural selection, as I hope Chapters 8 and 9 have demonstrated, really isn’t very difficult to understand. You don’t need mathematics to get the principle. Darwin was no mathematician; nor was Alfred Wallace, who discovered the idea independently, and only slightly later. Why did nobody get it before the nineteenth century?

  Why didn’t Aristotle (383–322 BC) get it? He is regarded as one of the world’s great thinkers. He pretty much invented the principles of logical thought. He observed and described animals and plants in meticulous detail. Yet he was totally clueless when it came to answering the obvious question they raise, namely ‘Why are they there?’ Archimedes (c.287–212 BC) had some supremely clever ideas, both in and out of his bath (search it on the web, although unfortunately the story of Archimedes leaping out of his bath may be another of those repeat-worthy myths like the ones we met in Chapter 3). But the idea of evolution by natural selection never occurred to him. Eratosthenes (276–194 BC) calculated the circumference of the Earth by comparing the length of a midday shadow at two places a known distance apart. Brilliant! He accurately estimated the tilt of the Earth’s axis (the tilt that gives us our seasons). Those feats are far cleverer than anything most of us could aspire to. Yet, although those clever old Greeks were surrounded by animals and plants (and of course humans), and they must have wondered how they came to be so purposeful, so beautifully ‘designed’, they never hit upon the extremely simple idea – Darwin’s idea. Nor did Galileo. Nor did Isaac Newton, who just might be the cleverest person who ever lived.* Nor did any of the great philosophers throughout history. The idea is so simple and so p
owerful, you’d think any fool could have seen it; any fool sitting in an armchair, with no great learning and no mathematics. You’d think it would be easier to solve than an average crossword clue (I speak with feeling, as I am hopeless at cryptic crosswords). Yet nobody hit upon it until the middle of the nineteenth century. This breathtakingly powerful yet simple idea, which had eluded the world’s greatest minds, finally occurred to two non-mathematical travelling naturalists and specimen-collectors, Charles Darwin and Alfred Wallace. It also seems to have occurred independently, around the same time, to a third man, a Scottish orchard-keeper called Patrick Matthew.

  Why did it take so long? Here’s what I think. I think the complexity, beauty and ‘purposefulness’ of living things must have seemed too obviously designed by an intelligent creator. So it required a major leap of courage to consider anything else. I don’t mean physical courage, like the courage of a soldier in battle. I mean intellectual courage: the courage to contemplate the apparently ridiculous, and say: ‘You cannot be serious – but let’s in any case go out on a limb and examine the possibility all the same.’ It had been ‘obviously’ ridiculous to suggest that a cannonball and a feather will fall at the same rate. But Galileo had the intellectual courage to examine the possibility and prove it. It seemed completely ridiculous that Africa and South America were once united and slowly drifted apart. But Wegener had the courage to see where the idea led. It must have seemed utterly ridiculous that something as obviously ‘designed’ as a human eye is actually not designed at all. But Darwin had the courage to examine that ‘ridiculous’ possibility. And now we know he was right. Right about that, and right about every last detail of every living thing.