The Science of Discworld Revised Edition by Terry Pratchett Read Free Book Online Page A

could pour as much money as we liked into developing antigravity or faster-than-light travel, and we’d get nowhere.
    When you can take a machine to bits and see how it works, you get a clear feeling for the constraints within which it has to operate. In such cases, you’re not going to confuse science and magic. The first cars required an extremely hands-on starting system – you stuck a big handle into the engine and literally ‘turned it over’. Whatever the engine did when it started, you knew it wasn’t magic. However, as technology develops it usually doesn’t
remain
transparent to the user. As more people began to use cars, more and more of the obvious technology was replaced by symbols. You worked switches with labels to get things to happen. That’s our version of the magic spell: you pull a knob called Cold Start and the engine does all the cold start things for itself. When Granny wants to drive she does not have to do much more than push the accelerator for ‘Go’. Little imps do the rest, by magic.
    This process is the core of the relation between science and magic in our own world. The universe into which we were born, and in which our species evolved, runs by rules – and science is our way of trying to work out what the rules are. But the universe that we are now constructing for ourselves is one that, to anyone other than a member of the design team and very possibly even to them, works by magic.
    A special kind of magic is one of the many things that have made humans what they are. It’s called education. It’s how we pass on ideas from one generation to the next. If we were like computers, we’d be able to
copy
our minds into our children, so that they would grow up agreeing with every opinion that we hold dear. Well, actually they wouldn’t, though they might start out that way. There is an aspect of education that we want to draw to your attention. We call it ‘lies-to-children’. We’re aware that some readers may object to the word ‘lie’ – it got Ian and Jack into terrible trouble with some literally-minded Swedes at a scientific conference who took it all terribly seriously and spent several days protesting that ‘It’s not a
lie
!’ It is. It is for the best possible reasons, but it is still a lie. A lie-to-children is a statement that is false, but which nevertheless leads the child’s mind towards a more accurate explanation, one that the child will only be able to appreciate if it has been primed with the lie.
    The early stages of education
have
to include a lot of lies-to-children, because early explanations have to be simple. However, we live in a complex world, and lies-to-children must eventually be replaced by more complex stories if they are not to become delayed-action genuine lies. Unfortunately, what most of us know about science consists of vaguely remembered lies-to-children. For example, the rainbow. We all remember being told at school that glass and water split light into its constituent colours – there’s even a nice experiment where you can
see
them – and we were told that this is how rainbows form, from light passing through raindrops. When we were children, it never occurred to us that while this explains the colours of the rainbow it doesn’t explain its shape. Neither does it explain how the light from the many different raindrops in a thundershower somehow combines to create a bright arc. Why doesn’t it all smudge out? This is not the place to tell you about the elegant geometry of the rainbow – but you can see why ‘lie’ is not such a strong word after all. The school explanation diverts our attention from the real marvel of the rainbow, the cooperative effects of all the raindrops, by trying to pretend that once you’ve explained the colours, that’s it.
    Other examples of lies-to-children are the idea that the Earth’s magnetic field is like a huge bar magnet with N and S marked on it, the picture of an atom as a miniature solar