Mikao Usui (臼井甕男, 15 August 1865 – 9 March 1926, commonly Usui Mikao in Japanese) is argued to have been the creator of a form of pseudoscientific spiritual practice called Reiki, a form of alternative therapy for the supposed treatment of physical, emotional, and mental diseases.
Source: “Mikao Usui”, English Wikipedia (CC BY-SA 4.0), excerpt
