The Science of Discworld IV Judgement Da - By Terry Pratchett, Ian Stewart Page 0,25

four cardinal points, and the Earth shakes when they adjust their positions – an imaginative explanation for earthquakes. They variously occur as a set of four, eight, or sixteen. The Amarakosha, a dictionary in verse written by the scholar Amarasinha around AD 380, states that eight male and eight female elephants hold up the world. It names the males as Airavata, Anjana, Kumunda, Pundarika, Pushpa-danta, Sarva-bhauma, Supratika and Vamana. It is silent about the names of the females. The Ramayana lists just four male world elephants: Bhadra, Mahápadma, Saumanas and Virúpáksha.

It may or may not be significant that the name Mahápadma is mentioned in Harivamsa and Vishnu Purana as a supernatural snake. Like dragons in the mythology of other cultures, it guards a hoard of treasure. Brewer’s Dictionary describes a ‘popular rendition of a Hindu myth in which the tortoise Chukwa supports the elephant Maha-pudma, which in turn supports the world’. This variant spelling seems to come from a misprint in a 1921 edition of one of the stories of the Mahabharata by the Indian freedom fighter and poet Sri Aurobindo:

On the wondrous dais rose a throne,

And he its pedestal whose lotus hood

With ominous beauty crowns his horrible

Sleek folds, great Mahapudma; high displayed

He bears the throne of Death.

However, this creature is clearly a giant cobra – unless you think the lotus hood is the elephant’s ears.

Our main interest in these stories, in the present context, is comparative mythology. The creation myths of many ancient cultures contain very similar elements. It is tempting to explain these similarities in terms of cross-cultural contact. It is becoming increasingly clear that the ancient world, at various times and in various places, was more advanced than we have previously imagined, and there is good archaeological evidence for trade over much longer distances than used to be assumed. However, temptation should probably be resisted, even so, because other explanations are more plausible. One is cultural convergence driven by human psychology and common environments.

Images such as the Earth rising from a primal ocean seem to be the sort of thing that naturally occurs to intelligent but uninformed human beings who try to explain where their world came from using human-centred thinking. Seas rise and fall with the tides, rocks appear and disappear. Floods drown low mounds, and then reveal them again as the waters recede. We take inspiration from nature, make it larger than life, and use our own invention to explain what we can’t understand. Creation myths open up windows into the human psyche. Ubiquitous natural phenomena, such as seas, mountains, volcanoes and earthquakes, suggest similar supernatural explanations. All ancient cultures were greatly influenced by the animals and plants that existed in their vicinity. If you live in a land full of possums and jaguars, it is no surprise if you develop possum gods and jaguar gods.

In many ways the differences between mythologies in disparate cultures are their most significant features. They suggest that the similarities may often result from some kind of convergent evolution, in which the same general supernatural explanation turns up independently because it has a certain logic – often of the Discworld kind – that appeals to the human mind. Explaining thunder as the gods throwing things, for example.

It is also interesting to see how myths evolve, like Chinese whispers, when they are passed on by oral tradition. Snakes become elephants. When the myths were preserved in written form, they still underwent dramatic changes before the invention of printing made it easy to mass-produce books. Even today, many of us can remember the general outline of a joke, or a story, but not the names of the characters. In mathematical circles, there are some standard stories about famous mathematicians, and the stories never change, but the famous mathematicians often do; the important point is that they should be famous. After that, it doesn’t greatly matter who they were – the story is just as funny, whoever you choose. The turtle joke in the next section is an example.

The logic of mythology can also sometimes shed a little light on scientific issues, by reminding us of the principal reason for adopting the scientific method: the human tendency towards self-deception. We all too easily accept some kinds of evidence, or some types of argument, when they confirm what we want to believe; we tend to reject them if they conflict with our beliefs.

In 2012 a Gallup poll found that 46% of American adults agreed that ‘God created human beings pretty much in their present