In Japanese folklore, satori (覚, "consciousness") are supernatural monsters (yōkai) who pass for living in the mountains of Hida and Mino provinces (modern Gifu Prefecture) and are able to read people's minds.
Humans encounter them along mountain trails or when resting in the mountains. After reading a person's mind, the satori says out loud the person's thoughts faster than a human could.
There is also a theory that they are the child incarnations of the mountain gods who came to destroy and borrow the form of the yōkai.
They may appear in front of people in mountain shelters and may even try to kill and eat them if they get the chance, but if something unexpectedly surprises the satori, they are seized with fear and run away.
Another theory claims that they pose no danger to people and would not dare to harm mountain workers, which makes it possible to cohabit with them.
A satori is described in Toriyama Sekien's Konjaku gazu zoku hyakki but since it is composed on the model of yamako (玃) in the Wakan Sansai Zue and other works and it even says "there are yamako deep in the mountains of Hida and Mino" in the text, Toriyama Sekien is said to have given it the name satori because they are able to read (satoru) people's minds.
The yamako was an ape-man of Chinese legends but in the Wakan Sansai Zue, it is an animal that reads people's minds in Hida and Mino and since the character 玃 can also be pronounced kaku, the character 覚 (also kaku) was used as appropriate for a replacement,
which was later misinterpreted as satori and thus it was this interpretation that gave rise to the legend of the satori as a different type of yōkai than the yamako.
Another theory posits that satori are modeled after yamabiko found in the Konjaku Gazu Zoku Hyakki, Hyakkai zukan, and other collections, but according to folklorist Kunio Yanagita in his book Yokai Dangi, the idea that satori read spirits and the legend that yamabiko can imitate voices have the same origin.