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The earliest known concept of pressure points can be seen in the South IndianVarma kalai based on Siddha. The concept of pressure points is also present in the old school Japanese martial arts; in a 1942 article in the Shin Budo magazine, Takuma Hisa asserted the existence of a tradition attributing the first development of pressure-point attacks to Shinra Saburō Minamoto no Yoshimitsu (1045–1127).
Hancock and Higashi (1905) published a book which pointed out a number of vital points in Japanese martial arts.
Accounts of pressure-point fighting appeared in Chinese Wuxia fiction novels and became known by the name of Dim Mak, or "Death Touch", in western popular culture in the 1960s.
While it is undisputed that there are sensitive points on the human body where even comparatively weak pressure may induce significant pain or serious injury, the association of kyūsho with notions of death have been harshly criticized.
References
Andrew Nathaniel Nelson, The Original Modern Reader's Japanese-English Character Dictionary, Tuttle Publishing, 2004, p.399.
It is also called Internal point.
Takuma Hisa Sensei, Shin Budo magazine, November 1942. republished as Hisa, Takuma (Summer 1990). "Daito-Ryu Aiki Budo". Aiki News. 85. Archived from the original on 2007-10-11. Retrieved 2007-07-18. "Yoshimitsu dissected corpses brought back from wars in order to explore human anatomy and mastered a decisive counter-technique as well as discovering lethal atemi. Yoshimitsu then mastered a technique for killing with a single blow. Through such great efforts, he mastered the essence of aiki and discovered the secret techniques of Aiki Budo. Therefore, Yoshimitsu is the person who is credited with being the founder of the original school of Daito-ryu."
Felix Mann: "...acupuncture points are no more real than the black spots that a drunkard sees in front of his eyes." (Mann F. Reinventing Acupuncture: A New Concept of Ancient Medicine. Butterworth Heinemann, London, 1996,14.), quoted by Matthew Bauer in Chinese Medicine TimesArchived 2009-01-22 at the Wayback Machine, vol 1 issue 4, Aug. 2006, "The Final Days of Traditional Beliefs? - Part One"