The Science of Discworld II

by Terry Pratchett

  ‘Just gods?’ said a man.

  ‘Oh, no. Anything at all,’ said Rincewind. ‘Gods, demons, nymphs, shepherds—’

  ‘No, I couldn’t do a shepherd,’ said the possible thespian. ‘I’m a carpenter. I don’t know shepherding.’

  ‘But you know godding?’

  ‘Well, yeah, that’s just … thundering and shouting and that kind of thing. Being a decent shepherd takes years of work.’

  ‘You can’t expect us to act like people,’ said another man. ‘That wouldn’t be right.’

  ‘It’s not respectful,’ said a third man.

  Yes, we mustn’t change things, thought Rincewind. The elves like that thinking. We mustn’t change things, in case they end up different. Poor old Phocian …

  ‘Well, can you do trees?’ he said. He was vaguely aware that actors warmed up by pretending to be trees, amongst other things, and this presumably prevented wooden performances.

  ‘Trees are all right,’ said a man. ‘They’re quite magical. But it wouldn’t be respectful to our friend over there to ask us to be carpenters.’

  ‘All right, then, trees. That’s a start. Now, stretch out your—’

  There was a roll of thunder and a goddess appeared. Her hair was in golden ringlets, her white robe flapped in the breeze, and there was an owl on her shoulder. The men ran away.

  ‘Well, my little trickster,’ said the goddess, ‘and what are you teaching them?’

  Rincewind clapped a hand over one eye for a moment.

  ‘That owl’s stuffed,’ he said. ‘You can’t fool me! No animals stay around elves without going mad!’

  The image of the goddess wavered as the Queen tried to maintain control, but glamour is susceptible to disbelief.

  ‘Oh, so brave?’ she said, defaulting to her usual appearance.

  She turned at a creaking noise behind her. The Luggage had tiptoed up and opened its lid.

  ‘That doesn’t frighten me,’ she said.

  ‘Really? It frightens me,’ said Rincewind. ‘Anyway, I’m simply brushing up their acting skills. Absolutely no problem there, is there? You should love these people. There’s dryads, nymphs, satyrs, centaurs, harpies and big giants with one eye, unless that’s a joke about sex I haven’t fully understood yet. They believe in all of them and none of them exist! Except possibly the one-eyed giant, that one’s a bit of a puzzler.’

  ‘We have seen their performances,’ said the Queen. ‘They are not respectful of their gods.’

  ‘But seeing is believing, isn’t it? And you must admit, they’ve got a lot of gods. Dozens.’

  He gave her a friendly smile, while hoping that she was keeping away from the local cities. They had a lot of temples in them, and shrines all over the place, but they also had a number of men who, while taking care to invoke the gods on every occasion, then appeared to expound ideas that didn’t seem to have any place for gods in them, except as observers or decoration. But the actors liked playing gods …

  ‘You’re up to something,’ said the Queen. ‘Everywhere we look, you wizards are teaching people art. Why?’

  ‘Well, it’s a rather drab planet,’ said Rincewind.

  ‘Everywhere we go, they’re telling stories,’ said the Queen, still slowly circling. ‘They’re filling the sky with pictures, too.’

  ‘Oh, the constellations?’ said Rincewind. ‘They don’t change, you know. Not like at home. Amazing. I tried getting one tribe to name that big one – you know, with what looks like a belt? I thought if they ended up calling it the Bursar, and that group of little stars off to the right became The Dried Frog Pills, it’d be a nice souvenir of our visit—’

  ‘You’re frightened of me, aren’t you,’ said the Queen. ‘All you wizards are frightened of women.’

  ‘Not me!’ said Rincewind. ‘Women are less likely to be armed!’

  ‘Yes you are,’ the Queen insisted, moving closer. ‘I wonder what your deepest desire is?’

  Not to be here right now would be favourite, Rincewind thought.

  ‘I wonder what I could give you,’ said the Queen, caressing Rincewind’s cheek.

  ‘Everyone knows that anything you get from the elves is gone by morning,’ said Rincewind, trembling.

  ‘Yet many things are transient but pleasurable,’ said the Queen, moving rather too close. ‘What is it you want, Rincewind?’

  Rincewind shuddered. There was no way he could lie.

  ‘Potatoes,’ he said.

  ‘Tuberous vegetables?’ said the Queen, her brows knitting in puzzlement,

  ‘Well, yes. They’ve got them on one of the other continents, but they’re not what I’d call spuds, and Ponder Stibbons says that if we left things as they were then by the time they’ve been brought over to this continent and bred up a bit it’d be the end of the world. So we thought we ought to ginger up the creativity level a bit.’

  ‘And that’s it? That’s why all you wizards are doing all this? Just to accelerate the breeding of a vegetable?’

  ‘The vegetable, thank you,’ said Rincewind. ‘And you did ask. The potato, in my opinion, is the crown of the vegetable kingdom. There’s roast potatoes, jacket potatoes, boiled potatoes, fried potatoes, curried potatoes—’

  ‘Just for a stupid tuber?’

  ‘—potato soup, potato salad, potato pancakes—’

  ‘All this for something that doesn’t even see daylight!’

  ‘—mashed potato, chipped potato, stuffed potato—’

  The Queen slapped Rincewind’s face. The Luggage bumped into the back of her legs. It wasn’t entirely sure what was happening here. There were some things humans did that could be misinterpreted.

  ‘Do you not think I could give you something better than a potato?’ she demanded.

  Rincewind looked puzzled.

  ‘Are we talking about a sour cream topping with chives?’ he said.

  Something fell out of Rincewind’s robe as he shifted uneasily. The Queen grabbed it.

  ‘What’s this?’ she said. ‘There’s writing all over it!’

  ‘It’s just a script,’ said Rincewind, still thinking about potatoes. ‘A sort of story of a play,’ he added. ‘Nothing important at all. People going mad and getting killed, that sort of thing. And a glowworm.’

  ‘I recognise this script! It’s from the future of this world. Why would you carry it around? What is so special? Hah, are there potatoes in it?’

  She leafed through the pages, as if she could read.

  ‘This must be important!’ she snapped. And vanished.

  One solitary page slid down to the ground.

  Rincewind bent down and picked it up. Then he shouted hotly at the empty air: ‘I suppose a packet of crisps is out of the question?’

  TWENTY-SIX

  LIES TO CHIMPANZEES

  A CENTRAL FEATURE OF HUMAN EXTELLIGENCE is the ability to infer what is going on in another person’s mind, to guess what the world looks like from their point of view. Which is what Rincewind is trying to stop the Queen of the Elves from doing. We can’t make such inferences with perfect accuracy; that would be telepathy, which is almost certainly impossible, because each brain is wired up differently and therefore represents the universe in its own special way. But we’ve evolved to be pretty good at guessing.

  This ability to get inside other people’s heads has many beneficial consequences. One is that we recognise other people as people, not just automata. We recognise that they have a mind, that to them the universe seems just as real and vivid as it does to us, but that the vivid things they perceive may not be the same as those that we perceive. If intelligent beings are going to get along together without too much friction, it’s important to realise that other members of your species have an internal mental universe, which controls their actions in the same way that your own mind controls yours.

  When you can put yourself inside another person’s mind, stories gain a new dimension. You can identify with a central character, and vicariously experience a
different world. This is the appeal of fiction: you can captain a submarine, or spy on the enemy, from the safety and comfort of an armchair.

  Drama has the same appeal, too, but now there are real people to identify with; people who play a fictional role. Actors, actresses. And they rely even more on getting inside other people’ss minds, especially the minds of fictional characters. Macbeth. The Second Witch. Oberon. Titania. Bottom.

  How did this ability arise? As usual, it seems to have come about because of a complicity between the internal signal-processing abilities of the brain and the external pressures of culture. It arose through an evolutionary arms race, and the main weapon in that race was the lie.

  The story starts with the development of language. As the brains of proto-humans evolved, getting larger, there was room in them for more kinds of processing tasks to be carried out. Primitive grunts and gestures began to be organised into a relatively systematic code, able to represent aspects of the outside world that were important to the creatures concerned. A complicated concept like ‘dog’ became associated with a particular sound. Thanks to an agreed cultural convention, anyone who heard that sound responded to it with the mental image of a dog; it wasn’t just a funny noise. If you try to listen to someone speaking a language that you know, focusing just on the noises that they are making and trying not to pick up the meaning of their words, you’ll find that it’s almost impossible. If they speak a language far removed from any that you know, however, their speech comes over as a meaningless gabble. It conveys less to you than a cat’s miaow.

  In the brain are circuits of nerve cells that have learned to decode gabble into meaning. We’ve seen that as a child grows, it begins by babbling a random assortment of phonemes, the ‘units’ of sound that a human mouth and larynx can produce. Gradually the child’s brain prunes the list down to those sounds that it hears from its parents and other adults. While it is doing that, the brain is destroying connections between nerve cells that seem to be obsolete. Quite a lot of the early mental development of an infant consists of chopping down a randomly connected, all-purpose brain, and pruning it into a brain that can detect the things that are considered important in the child’s culture. If the child is not exposed to much linguistic stimulus in early childhood – such as a ‘feral’ child brought up by animals – then they can’t learn a language properly in later life. After about the age of ten, the brain’s ability to learn language fades away.

  Much the same happens with other senses, in particular the sense of smell. Different people smell the same thing differently. To some, a particular odour may be offensive, to others innocuous, and to yet others, nonexistent. As with language, there are cultural biases to certain smells.

  The primary function of language – by which we mean ‘the main evolutionary trick that made it advantageous, leading to its preservation and enhancement by natural selection’ – is to convey meaningful messages to other members of the same species. We do this in several ways: ‘body language’ and even bodily odours convey vivid messages, largely without our being conscious of them. But spoken language is far more versatile and adaptable than the other kinds, and we are very conscious of what others are saying. Especially when it is about us.

  One of the commonest generic evolutionary tricks is to cheat. As soon as a bunch of organisms has evolved some specific ability or behaviour, a new possibility arises: subverting that behaviour. Predictable behaviour patterns provide a natural springboard from which organisms can leap out into the space of the adjacent possible. Bees evolved the abilities to collect nectar and pollen, to feed themselves. Later, we subverted that activity by providing them with better homes than they would find in nature. We get to steal their honey, by providing them with hives as the up-market adjacent-possible homes.

  Many evolutionary trends have arisen from subversion. So, as the ability to put specific thoughts into the minds of others became established, it was natural for evolution to experiment with methods for subverting that process. You didn’t have to put your own genuine thoughts into the minds of others: you could try to put different thoughts there. Perhaps you could gain an advantage by misleading the creatures you were ‘communicating’ with. The result was the evolution of lying.

  Many animals tell lies. Monkeys have been observed making the troupe’s ‘danger’ call-sign. Then, as the rest of the troupe heads off for cover, the liar grabs the food that they have temporarily abandoned. On a more primitive but just as effective level, mimicry in the animal kingdom is a form of lying. A harmless hover-fly displays the black-and-yellow warning bands of a wasp, telling the lie ‘I am dangerous, I can sting’.

  As humanity evolved, those monkey lies turned into more sophisticated ape lies, then hominid lies, then human lies. As we became more intelligent, our capacity for telling lies co-evolved alongside another important ability: the ability to tell when someone was lying to you. A monkey troupe can evolve several defences against a member who abuses the danger-signal for his own ends. One is to recognise that this individual can’t be trusted, and ignore their calls. The nursery tale of the little boy who cried ‘wolf’ exposes the dangers inherent in this area, both for the troupe and for the individual. Another is to punish the individual for telling the lie. A third is to evolve the ability to tell the difference between a lying danger-signal and a true one. Is the monkey crying ‘danger’ staring at someone else’s food with a greedy glint in their eye?

  Just as there are sound evolutionary reasons for telling lies, so there are sound evolutionary reasons for being able to detect them. If others are trying to manipulate you to their advantage, then it is very probably to your disadvantage. So it is in your best interests to realise that, and avoid being manipulated. The result is an inevitable arms race, in which the ability to tell lies is played off against the ability to detect them. It is no doubt still going on, but already the result is some very sophisticated lying, and some very sophisticated detection. Sometimes the look on a person’s face tells us they’re telling an untruth; sometimes the tone of voice.

  One effective way to recognise a lie is to put yourself inside the other person’s mind, and ask yourself whether what they are saying is consistent with what you have convinced yourself they are thinking. For instance, they are saying what a sweet little child you have, but you remember from previous encounters that usually they can’t stand kids. Maybe your child is different, of course, but then you notice that worried look in their eyes, as if they’d rather be somewhere else …

  Empathy is not just a nice way to understand someone else’s point of view. It’s a weapon that you can use to your own advantage. Having understood their point of view, you can compare it with what they’re saying, and work out whether to believe them. In this manner, the existence of lies in language’s phase space of the adjacent possible encouraged the development of human empathy, and with it, individual intelligence and collective social cohesion. Learning to tell lies was a major step forward for humanity.

  We can put ourselves inside the minds of other people with some degree of credibility, because we are people ourselves. We do at least know what it’s like to be a person. But even then, we are probably deluding ourselves if we think that we really know exactly what’s going on inside someone else’s mind, let alone what that feels like to them. Each human mind is wired differently, and is the product of its owner’s own experiences. It is even more problematic whether we can imagine what it is like to be an animal. On Discworld, an accomplished witch can put herself inside an animal’s mind, as we see, for instance, in this passage from Lords and Ladies:

  She Borrowed. You had to be careful. It was like a drug. You could ride the minds of animals and birds, but never bees, steering them gently, seeing through their eyes. Granny Weatherwax had many times flicked through the channels of consciousness around her. It was, to her, part of the heart of witchcraft. To see through other eyes …

  … through the eyes of gnats, seeing the slow patterns of time in th
e fast pattern of one day, their minds travelling rapidly as lightning …

  … to listen with the body of a beetle, so that the world is a three-dimensional pattern of vibrations …

  … to see with the nose of a dog, all smells now colours …

  It’s a poetic image. Does a dog ‘see’ smells? There is a folk belief that smell is far more important to a dog than sight, but this could well be an exaggeration based on the more credible observation that smell is more important to dogs than it is to humans. But even here we must add ‘consciously, at least’, because we react subconsciously to pheromones and other emotionally loaded chemicals. Some years ago David Berliner was working on the chemicals in human skin, and he left an open beaker containing some skin extracts on the laboratory bench. Then he noticed that his lab assistants were becoming distinctly more animated than usual, with a lot of camaraderie and mild flirtation. He froze the extract and put it away in the laboratory refrigerator for safekeeping. Thirty years later, he analysed the substances in the beaker and found a chemical called androstenone, which is rather like a sex hormone. A series of experiments showed that this chemical was responsible for the animated behaviour. However, androstenone has no smell. What was going on?

  Some animals possess a ‘vomeronasal’ organ (often called the ‘second nose’). This is a small region of tissue in the nose, which detects certain chemicals but is separate from the standard olfactory (smelling) system. The conventional wisdom had long been that humans do not possess a vomeronasal organ, but the curious behaviour of his assistants made the scientist wonder. Berliner discovered that the conventional wisdom was wrong: some humans, at least, do have a vomeronasal organ, and it responds to pheromones. Those are special chemicals that trigger strong responses in animals, such as fear or sexual arousal. The vomeronasal organ’s owners are not consciously aware that they are sensing anything, but boy, do they respond.

  This story shows how easily we can get sensations wrong. In this case, you know what it vomeronasally smells like to be a human: you don’t feel anything at all, not consciously. But you certainly respond! So your reactions, and what they ‘feel like’, are very different. The sounds we hear, the sensations of heat and cold on our skin, the smells that assail our nostrils, the unmistakable taste of salt … all these are qualia, vivid ‘feelings’ stuck on to our perceptions by our minds to help us recognise them more readily. They have a basis in reality, yes, but they are not real features of the outside world. They must be real features of brain architecture and function, real things happening in real nerve cells, but that level of reality is very different from the level that we perceive.