Namazu

Under the islands of Japan, down in the mud, lies an enormous catfish.

The deity of Kashima holds it down with a stone — the kaname-ishi, the keystone rock, pressed on the fish's head.

When the god's attention wanders, the catfish thrashes.

That's the earthquake.

The stone is real and you can go and look at it

The kaname-ishi is at Kashima Shrine in Ibaraki. It sticks up out of the ground a few inches. Unimpressive, honestly — a modest rounded stone in an enclosure.

The tradition says it goes down forever.

And there's a famous test of that. A lord of Mito — the story attaches it to Tokugawa Mitsukuni — had it excavated, to settle the question.

They dug. They kept digging. They could not find the bottom, and gave up.

I can't verify that dig. But the shrine has been telling it for a very long time, and the stone is still there, still a few inches proud of the earth, still attached to the claim that it is the visible tip of something the size of the country.

The cosmology is younger than it feels

Here's the honest bit, and it's important.

The catfish-earthquake connection isn't ancient. It doesn't appear until the late 17th century, and it peaks in the 19th.

That's very recent, for something that reads as primordial. This is not a belief that came down from the age of the gods. It assembled itself in the early modern period, in a literate, urban, commercial society — which turns out to matter enormously for what happened next.

There's a precipitating story, from 1855. An eel fisherman noticed the catfish behaving wildly, hours before the Ansei Edo earthquake struck that night.

Which — for what it's worth — is not a closed question. Catfish sensitivity to pre-seismic activity remains a real subject of research. Nobody has demonstrated it well enough to build a warning system on, and plenty of studies have found nothing. But the fisherman was reporting something people had noticed, and scientists have been intermittently checking it ever since.

And then 1855, when the catfish became a political cartoon

This is the part that makes the namazu unlike anything else in Japanese folklore.

The Ansei Edo earthquake killed thousands and flattened much of the city.

And within weeks, the print shops of Edo were flooded with namazu-e — "catfish pictures." Hundreds of designs. Cheap, fast, anonymous woodblock prints, sold everywhere, produced faster than the authorities could react.

The early ones are what you'd expect. The god subduing the fish. The fish grovelling and apologizing to the people of Edo.

And then the designs turn.

The catfish becomes the god of world-rectification

Yonaoshi daimyōjin. "Great deity of world-rectification."

The argument in these prints is astonishing, and it is made in pictures, without a word of editorial.

The earthquake shook the wealth out of the rich.

The prints show hoarded gold disgorged from the storehouses of merchants and landlords — coins spilling, raining down onto the carpenters, plasterers, and labourers who were about to be paid very well indeed to rebuild the city.

The catfish isn't a disaster any more. It's a redistribution event.

The monster that killed thousands is recast as the people's avenger — performing, in one night, the levelling that the social order never would.

Censors chased them. There were too many.

Why this is the best-documented thing in the whole tradition

Because nearly every other monster in Japanese folklore reaches us through somebody's summary — a scholar's note, a village informant, a catalogue entry.

The namazu reaches us as hundreds of surviving prints, made in a specific month, in response to a specific catastrophe, by people who were living in the rubble at the time.

You can look at what ordinary Edo residents actually thought about wealth and disaster and blame, in the weeks after their city fell down, because they drew it and sold it for coppers on the street.

A yokai as political cartoon. Fully documented, gloriously visual, and every last sheet of it out of copyright.