The Morris dance is common to all inhabited worlds in the multiverse.
It is danced under blue skies to celebrate the quickening of the soil and under bare stars because it's springtime and with any luck the carbon dioxide will unfreeze again. The imperative is felt by deep-sea beings who have never seen the sun and urban humans whose only connection with the cycles of nature is that their Volvo once ran over a sheep.
It is danced innocently by raggedy-bearded young mathematicians to an inexpert accordion rendering of "Mrs Widgery's Lodger" and ruthlessly by such as the Ninja Morris Men of New Ankh, who can do strange and terrible things with a simple handkerchief and a bell.
And it is never danced properly.
Except on the Discworld, which is flat and supported on the backs of four elephants which travel through space on the shell of Great A'Tuin, the world turtle.
And even there, only in one place have they got it right. It's a small village high in the Ramtop Mountains, where the big and simple secret is handed down across the generations.
There, the men dance on the first day of spring, backwards and forwards, bells tied under their knees, white shirts flapping. People come and watch. There's an ox roast afterwards, and it's generally considered a nice day out for the all the family.
But that isn't the secret.
The secret is the other dance.
In the village in the Ramtops where they understand what the Morris dance is all about, they dance it just once, at dawn, on the first day of spring. They don't dance it after that, all through the summer. After all, what would be the point? What use would it be?
But on a certain day when the nights are drawing in, the dancers leave work early and take, from attics and cupboards, the other costume, the black one, and the other bells. And they go by separate ways to a valley among the leafless trees. They don't speak. There is no music. It's very hard to imagine what kind there could be.
The bells don't ring. They're made of octiron, a magic metal. But they're not, precisely, silent bells. Silence is merely the absence of noise. They make the opposite of noise, a sort of heavily textured silence.
And in the cold afternoon, as the light drains from the sky, among the frosty leaves and in the dampair, they dance the other Morris. Because of the balance of things.
You've got to dance both, they say. Otherwise you can't dance either.