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universe-centred science and human-centred myth-making can hardly fail to ask a supplementary question:
What keeps the elephants up?
If the idea of an ordinary elephant hovering in mid-air is ludicrous, how much more so is that of a vast, extraordinarily heavy elephant doing the same? Discworld’s answer is A’Tuin, a giant space-faring turtle. The turtle’s shell provides a firm place for the elephants to stand. As a cosmology, it all hangs together pretty well … but of course a further question arises:
What keeps the turtle up?
It might seem that we could go on like this indefinitely, but at this point observations of nature come into play. The natural world provides a long list of exceptions to the belief that the natural place of any object is on the ground: celestial bodies, clouds, birds, insects and all water-borne creatures – fish, crocodiles, hippos, whales and, crucially, turtles.
However, we can prune the list. Birds and insects do not remain aloft indefinitely; wait long enough and they do, in fact, descend to their natural place, typically a tree or a bush. The Sun, Moon and stars do not inhabit the terrestrial realm at all, so there is no reason to expect them to behave in a human-centred way – and they don’t. Assigning them to the realm of the supernatural has so many attractions that it becomes virtually unavoidable. The same arguably goes for clouds, which have a habit of producing awe-inspiring phenomena such as thunder and lightning. Scratch clouds. Crocodilesand hippos are out: they spend a lot of time on land. Fish are not renowned for doing that, but no sensible person would try to fit four elephants on top of a fish.
Which leaves turtles.
Small turtles spend a lot of time on rocks, but no one in their right mind would expect a small turtle to hold up four giant world-bearing elephants. Big turtles come out onto land to lay their eggs, but that’s a mystical event and it doesn’t cast serious doubt on the theory that a turtle’s natural place is in water. Where, please notice,
it does not require support
. It can swim. So it stands to reason that any self-respecting giant space-faring turtle will swim through space, which implies that it needs no artificial support to avoid falling. Examining the animal more closely, a world-spanning turtle seems ideal as a support for giant elephants. It is hard to imagine what could perform the task better.
In short, Discworld is, as stated earlier, the sensible way to make a world.
By comparison, Roundworld makes no sense. It’s the wrong shape, it’s held up by nothing, and it swims through space unaided despite not being the right shape to swim through
anything
. Basically, it’s a giant rock, and you all know what rocks do when you throw them in the lake. It is hardly surprising that it took the wizards a long time to come to terms with the way Roundworld organises itself. Accordingly, we should not be surprised to find that pre-scientific humanity had the same problem.
Flat worlds, giant elephants, world-bearing turtles … how did these enter the human psyche? One of the ironies of human-centred thinking is that it is unavoidably attracted to superhuman questions – the big picture. What are we? Why are we here? Where did it all come from? And one of the ironies of universe-centred thinking is that it is far better equipped to answer human-scale questions than cosmic ones.
If you want to find out how the rainbow gets its colours, you can pass light through a glass prism in a darkened room. This is what Isaac Newton did in about 1670, though he had to overcome some practical problems. The worst was his cat, which kept wandering into the attic to find out what Isaac was doing, pushing open the door and letting light in. So the ingenious scientist cut a hole in the door and nailed up a piece of felt, inventing the cat flap. When puss had kittens, he added a smaller hole next to the big one, which probably seemed logical at the time. fn1
What keeps the elephants up?
If the idea of an ordinary elephant hovering in mid-air is ludicrous, how much more so is that of a vast, extraordinarily heavy elephant doing the same? Discworld’s answer is A’Tuin, a giant space-faring turtle. The turtle’s shell provides a firm place for the elephants to stand. As a cosmology, it all hangs together pretty well … but of course a further question arises:
What keeps the turtle up?
It might seem that we could go on like this indefinitely, but at this point observations of nature come into play. The natural world provides a long list of exceptions to the belief that the natural place of any object is on the ground: celestial bodies, clouds, birds, insects and all water-borne creatures – fish, crocodiles, hippos, whales and, crucially, turtles.
However, we can prune the list. Birds and insects do not remain aloft indefinitely; wait long enough and they do, in fact, descend to their natural place, typically a tree or a bush. The Sun, Moon and stars do not inhabit the terrestrial realm at all, so there is no reason to expect them to behave in a human-centred way – and they don’t. Assigning them to the realm of the supernatural has so many attractions that it becomes virtually unavoidable. The same arguably goes for clouds, which have a habit of producing awe-inspiring phenomena such as thunder and lightning. Scratch clouds. Crocodilesand hippos are out: they spend a lot of time on land. Fish are not renowned for doing that, but no sensible person would try to fit four elephants on top of a fish.
Which leaves turtles.
Small turtles spend a lot of time on rocks, but no one in their right mind would expect a small turtle to hold up four giant world-bearing elephants. Big turtles come out onto land to lay their eggs, but that’s a mystical event and it doesn’t cast serious doubt on the theory that a turtle’s natural place is in water. Where, please notice,
it does not require support
. It can swim. So it stands to reason that any self-respecting giant space-faring turtle will swim through space, which implies that it needs no artificial support to avoid falling. Examining the animal more closely, a world-spanning turtle seems ideal as a support for giant elephants. It is hard to imagine what could perform the task better.
In short, Discworld is, as stated earlier, the sensible way to make a world.
By comparison, Roundworld makes no sense. It’s the wrong shape, it’s held up by nothing, and it swims through space unaided despite not being the right shape to swim through
anything
. Basically, it’s a giant rock, and you all know what rocks do when you throw them in the lake. It is hardly surprising that it took the wizards a long time to come to terms with the way Roundworld organises itself. Accordingly, we should not be surprised to find that pre-scientific humanity had the same problem.
Flat worlds, giant elephants, world-bearing turtles … how did these enter the human psyche? One of the ironies of human-centred thinking is that it is unavoidably attracted to superhuman questions – the big picture. What are we? Why are we here? Where did it all come from? And one of the ironies of universe-centred thinking is that it is far better equipped to answer human-scale questions than cosmic ones.
If you want to find out how the rainbow gets its colours, you can pass light through a glass prism in a darkened room. This is what Isaac Newton did in about 1670, though he had to overcome some practical problems. The worst was his cat, which kept wandering into the attic to find out what Isaac was doing, pushing open the door and letting light in. So the ingenious scientist cut a hole in the door and nailed up a piece of felt, inventing the cat flap. When puss had kittens, he added a smaller hole next to the big one, which probably seemed logical at the time. fn1
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