Japanese writings that adopt Chinese traditions contain essentially three basic types of visual representation of the human body.[1]
The first is a flow chart of the ‘tracts and channels’ (Jap. keiraku經絡) below the skin that serve the circulation of the pneuma-like Qi (Jap. ki氣). Representations of this type show the male body from the front, side, and back. The organs are usually missing. In addition to pictures of the entire network, we also find some representations that demonstrate individual tracts. In many of these cases, half-naked figures that remind us of Chinese monks and scholars are depicted. This type of representation invariably displays the human body as alive and pervaded by dynamic flows (fig.1 left).)
The second type presents the so-called ‘five full organs’ or ‘five viscera’ (i.e., the liver, heart, spleen, lung, kidney) and ‘six hollow organs’ or ‘six bowels’ (i.e., the large intestine, gall bladder, urinary bladder, stomach, small intestine, and ‘triple burner’), and the spine. ... Certain characteristics of the eleven organs mentioned above are described in many texts, but these organs were always seen in terms of their functional relationships with the tracts and channels and the flow of Qi. Thus, when the body was ill, individual organs were never considered as isolated objects for diagnosis or therapy. This also explains in part why little need was felt for more precise anatomical observations and descriptions.
http://wolfgangmichel.web.fc2.com/pu...9/089index.htm
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Yamawaki Tōyō was the first one to carry out a government-authorized autopsy in Kyoto in 1754. Sugita Genpaku was inspired by Yamawaki’s findings and decided to study and revise traditional teachings. He attended one of the rare occasions in 1771 when a body was dissected. According to Uematsu, these dissections have led to the introduction of new, more accurate anatomy books in Japan. Even though dissection was still controlled by the government for another 80 years, there was a revolutionary change that was caused by the scientific methods that described facts based on observation instead of Confucian theories (Uematsu, 1990:163)
Read more about Toyo Yamawaki on page 235 here, and how he had to struggle to have traditional Confucian ideas overturned by simply having people look for themselves ...
https://books.google.co.jp/books?id=...organs&f=false