Koishi Genshun (小石元俊)

Genshun KOISHI (1743-February 9, 1809) was a Rangakusha (a person who studied Western sciences by means of the Dutch language) and Ranpoi (a person who studied Western medicine by means of the Dutch language) in the late Edo period.
Genshun' was his by-name, and his real name was 'Kokuzui.'
His childhood name was 'Taikichi.'
His azana (courtesy name in adulthood) was 'Yuso,' and his go (pseudonym) were 'Daigu' and 'Hekikasan.'
Genzui KOISHI was his children. Hosaku SAITO, Hakumin NANBU, and Sokichi HASHIMOTO numbered among his pupils.

His master's teacher was Toyo YAMAWAKI, and Genshun was a leading proponent of Ranigaku (Western medicine) in Kansai (western Japan). His name can be found in "Rangaku Kotohajime" (The Beginning of Dutch Studies) authored by Genpaku SUGITA because he was acquainted with Rangakusha in Edo, such as Genpaku and Gentaku OTSUKI. Genshun is also considered a person who ensured liaison between eastern and western Rangakusha.

Brief Personal History

He was born in the village of Katsura, Yamashiro Province (currently, Katsura, Nishikyo Ward, Kyoto City). His father came from the Rinno family, the chief retainer of the Obama Domain in Wakasa Province, and it is said that his father changed his name to 'Koishi' while leading an itinerant life. His mother, the second wife, was a daughter from the Shibahara family. In 1750, Genshun moved to Osaka, accompanying his father.
Aspiring to study medicine, he became a pupil of Gensen TANNOWA, the disciple of Toyo YAMAWAKI and a doctor for the Yanagawa Domain, and he changed his name to 'Genshun.'
On referral from Gensen, he also studied under Dokshoan NAGATOMI, who was also the disciple of Toyo, and learned the Western medicine. In Nagatomi's training school, he was called 'the three greatest talents,' together with Nanmei KAMEI and Koshuku ODA. He also practiced Zen under Jiun, a bonze in Kawachi.

In 1764, his father passed away. In this period, he traveled from place to place in western provinces. In1769, he opened Eiseikan (Hall of Hygiene) in Osaka. Influenced by Nanmei KAMEI, he enrolled in a government-backed school operated by Kien MINAGAWA and immersed himself in writing the book "Genen" (Fundamental Flow), whereby he criticized the old-fashioned medicine based on Onmyo-gogyo-setsu (Chinese traditional pseudo-science built on five elements). In Minagawa's school, he enjoyed friendship with Ritsuzan SHIBANO and others and learned history from Shunsui RAI. He was also acquainted with famous intellectuals such as Gyokudo URAGAMI and Kenkado KIMURA.

In 1783, he dissected a human body for examination in Fushimi. He had a spouse in this year. He had his son, Genzui KOISHI, become a pupil of Santo SHINOZAKI, his friend in Osaka, when Genzui was still a young child.

Energized by "Kaitai Shinsho" (the historic Japanese translation of a Dutch anatomical text) published in Edo in 1774, he visited Genpaku SUGITA and Gentaku OTSUKI in a row and stayed in Edo to collect information, sojourning at Otsuki's residence. In 1788, his book "Genen" was burned due to the Great Kyoto Fire of the Tenmei period. He dissected a human body also in 1796 and reported results in his book "Seyaku-in Kainantai Zozu" (Pharmacy Institution Edition of the Anatomy of Male's Body). In 1801, he opened his own medicine school, Kyuri-do, in Kyoto and contributed to the spread of Ranguku in Kansai. Through join-investment with Shigetomi HAZAMA, he stationed Sokichi HASHIMOTO, an umbrella craftsman, to Shiran-do in Edo (for the master of Rangaku). Genshun died at the age of 66.

His works are "Genen," "Guide to Medical Study," and "Yuin Shin-ron" (Theory of Psychological Causes). His graveyard is located at Koho-an, a subsidiary temple within Daitoku-ji Temple, in Kita Ward, Kyoto City.