Yokai, Yurei, or Kami? How Japan Sorts Its Mysterious Beings

Yokai, ghosts, and gods. All of them are invisible, mysterious beings. So where do you draw the line? Japanese folklore studies offer one surprisingly simple answer: it depends on whether people worship them. The same strange presence becomes a kami (a Shinto god) when it is honored with offerings, and a yokai when it is simply feared.

The dividing line: worship

This idea was made widely known by the folklorist Komatsu Kazuhiko. Among beings beyond human power, those that are welcomed with shrines and festivals are kami; those that aren't are yokai. In other words, they aren't different by nature. What changes the name is how people relate to them.

Seen this way, yokai and kami sit on the same continuum. A god that is no longer worshipped may slip into stories as a yokai, and something once feared may be enshrined and become a god. The border isn't a wall. It sways and shifts.

Yanagita Kunio and the "fallen gods"

Earlier still, Yanagita Kunio, the founder of Japanese folklore studies, suggested that many yokai might be former gods who had come down in the world. As faith faded and no one was left to worship them, those gods were gradually retold as frightening creatures.

The kappa of rivers and ponds is often given as an example: perhaps it was once a water god. Not every yokai fits this pattern, though, and later scholars pointed out many cases where it doesn't work. Even so, his idea of looking at yokai and gods as part of one story is said to have been an important step.

When a ghost becomes a god

And ghosts? A yurei is the spirit of a specific person who has died, appearing in this world. That's a big difference from yokai, which usually have no personal name.

Ghosts too, especially vengeful spirits called onryo, could become gods through worship. The best-known case is Sugawara no Michizane, a court scholar who was exiled from the capital and died in Dazaifu. His angry spirit was feared to have brought disasters on the capital, and he was later enshrined as Tenjin. Today he is cherished as the god of learning, the patron of students before exams. Calming a feared spirit and turning it into a protector, a belief known as goryo shinko, is another example of how worship changes a being's face.

The in-between faces in our Yokaipedia

Look through the Pixel Yokai Yokaipedia with this in mind, and you'll spot some residents of the borderland.

• Yurei: someone's spirit. Honored properly, it might show a different face
• Zashiki-warashi: said to bring prosperity to a house, and sometimes described more like a household guardian than a yokai
• Namahage: it looks like an ogre, but in its home region it is welcomed as a visiting god

Yokai, ghost, or god? Instead of sorting them strictly, try asking how people have lived alongside them. The mysterious beings of Japan start to feel a lot closer.