The Science of Discworld Revised Edition by Terry Pratchett Page B

Prickly, in a funny sort of way.’
    H EX rattled. Ponder walked back and looked down at the paper.
    ‘It almost feels
sticky
when I move my fingers,’ said the Dean.
    ‘Er … Dean?’ said Ponder, stepping back carefully. ‘I think it would be a really good idea if you pulled your hand out very, very carefully and really very soon.’
    ‘That’s odd, it’s beginning to tingle –’
    ‘Right now, Dean! Right now!’
    For once, the urgency in Ponder’s voice got through the Dean’s cosmic self-confidence. He turned to argue with Ponder Stibbons just a moment before a white spark appeared in the centre of the sphere and began to expand rapidly.
    The sphere flickered.
    ‘Anyone know what caused that?’ said the Senior Wrangler, his face bathed in the growing light of the Project.
    ‘I
think
,’ said Ponder slowly, holding up H EX ’s write-out, ‘it was Time and Space starting to happen.’
    In H EX ’s careful writing, the words said: +++ In The Absence Of Duration And Dimension, There Must Be
Potentiality. +++
    And the wizards looked upon the universe that was growing within the little sphere and spake amongst themselves, saying, ‘It’s rather a small one, don’t you think? Is it dinner time yet?’
    Later on, the wizards wondered if the new universe might have been different if the Dean had waggled his fingers in a different way. Perhaps, within it, matter might have naturally formed itself into, say, garden furniture, or one giant nine-dimensional flower a trillion miles across. But Archchancellor Ridcully pointed out that this was not very useful thinking, because of the ancient principle of WYGIWYGAINGW . 1
    1 ‘What You Get Is What You’re Given And It’s No Good Whining.’

SIX
BEGINNINGS AND BECOMINGS

    PONTENTIALITY IS THE key.
    Our immediate task is to start from a lot of vacuum and a few rules, and convince you that they have enormous potentiality. Given enough time, they can lead to people, turtles, weather, the Internet – hold it.
Where did all that vacuum come from?
Either the universe has been around forever, or once there wasn’t a universe and then there was. The second statement fits neatly with the human predilection for creation myths. It also appeals to today’s scientists – possibly for the same reason. Lies-to-children run deep.
    Isn’t vacuum just … empty space? What was there before we had space? How do you make space? Out of vacuum? Isn’t that a vicious circle? If in the past we didn’t have space, how can there have been a ‘there’ for whatever it was to exist in? And if there wasn’t anywhere for it to exist, how did it manage to make space? Maybe space was there all along … but why? And what about
time
? Space is easy compared to time. Space is just … somewhere to put matter. Matter is just … stuff. But time … time flows, time passes, time makes sense in the past and the future but not in the instantaneous, frozen present. What makes time flow? Could the flow of time be stopped?
What would happen if it did?
    There are little questions, there are medium-sized questions, and there are big questions. After which there are even bigger questions, huge questions, and questions so vast that it is hard to imagine what kind of response would count as an answer.
    You can usually recognize the little questions: they look immensely complicated. Things like ‘What is the molecular structure of the left-handed isomer of glucose?’ As the questions get bigger, they become deceptively simpler: ‘Why is the sky blue?’ The
really
big questions are
so
simple that it seems astonishing that science has absolutely no idea how to answer them: ‘Why doesn’t the universe run backwards instead?’ or ‘Why does red look like
that
?’
    All this goes to show that it’s a lot easier to ask a question than it is to answer it, and the more specialized your question is, the longer are the words that you must invent to state it. Moreover, the bigger a question is, the