Also called Sakuma Zōzan, Shōzan (佐久間象山, 1811-1864) was a progressive samurai intellectual of the Bakumatsu period.

Born in Matsushiro, the castle town of the Matsushiro domain (松代藩 Matsushiro-han, modern-day Nagano Prefecture), Shozan studied Chinese learning (漢学) under his father, a scholar-administrator of the domain and Satō Issai (佐藤 一斎, 1772–1859), a professor at the Shōheikō (昌平黌), a Confucian academy in Edo (present-day Tokyo). Just like many other intellectuals of his time, Shozan was alarmed by the rising power of Western nations as illustrated by China's humiliation in the Opium War (1839-42).

From 1842 onward, he studied rangaku (蘭学, "Dutch learning" or Western Studies in Dutch language), thereby exploring how Japan could preserve its security and independence from Western encroachment, under many scholars of Western learning, many of whom he was to surpass in a few years, Egawa Tarōzaemon (江川太郎左衛門, 1801-55), Shimosone Kinzaburō (1806-74), Kurokawa Ryoan (黒川良安, 1817-90), Tsuboi Shindo (坪井信道, 1795-1848), and others. He soon became an expert on Western-style gunnery and military tactics and opened his private school of Western gunnery in Edo in 1850, thus expanding his fame. Among those who flocked to the school were some of the most illustrious figures of Japan in the second half of the nineteenth century: Yoshida Shōin, Sakamoto Ryōma, Nakaoka Shintarō (中岡慎太郎, 1838-67), Hashimoto Sanai (橋本左内, 1834-59), Katō Hiroyuki (加藤弘之, 1836-1916), and Nishimura Shigeki (西村茂樹, 1828-1902).

As Shōzan immersed himself in the technical knowledge of the West during the 1840s, he conducted a series of experiments. Relying on the Dutch translation of a French encyclopedia by Noël Chomel, he produced glass in 1844. Following other Dutch books, he later cast a Western-style bronze cannon and conducted experiments with electricity based on the elekiter.

In Matsushiro, he encouraged the eating of pork, a relatively new dietary habit, and even raised some hogs. He also introduced the large-scale cultivation of potatoes and tried – unsuccessfully – to mine copper and lead. At the age of 42, he married Katsu Junko, Katsu Kaishu's 16-year-old sister.

By the time Commodore Perry's black ships entered Edo Bay in July 1853, Shōzan had come to believe that studying Western-language books was not sufficient, comparing it to "scratching an itchy foot through one's shoe." He maintained that the most effective way of knowing the Western enemy was to send the talented to the enemy's lands to observe conditions there. This belief led him to encourage his disciple Yoshida Shōin to try to go abroad by stowing away on board a Western vessel in violation of Japan's national seclusion policy. When Shōin's second attempt failed in 1854, Shōzan's complicity was revealed. This disclosure brought about an eight-year-long domiciliary confinement at Matsushiro. During the early part of his house arrest, he wrote his famous work, Seikenroku (勝海舟, Reflections on My Errors). Much of the work, written in Chinese, consists of a criticism of the general ignorance of Western science on the part of Confucian scholars and the ineptness of the shogunate in dealing with Perry, thereby concerning itself more with others' errors than with Shōzan's.

In June 1864, he was made an adviser to the shogunate on defence matters and went to Kyōto, then the hotbed of sonnō jōi (尊皇攘夷 "Revere the Emperor, Expel the Barbarians") advocates. In sending Shōzan to Kyōto, the shogunate appears to have intended not only to have him serve as an adviser but also to win the sonnō jōi faction over to the movement for the union of court and shogunate (公武合体 kōbu gattai). Before he could exercise any influence on behalf of the shogunate, he was assassinated by a sonnō jōi adherent, Kawakami Gensai (河上彦斎, 1834-72), in August 1864.


Shōzan has been described as a creative and diligent, yet exceedingly proud, uncompromising, and even immodest scholar. The more he learned about the West, the more profoundly he thought of himself. Despite being only a rear vassal (陪臣 baishin) of the shōgun, he felt that the reputation he enjoyed as a scholar of Western learning, together with the Confucian emphasis on men of talent, entitled him to convey his views on national defence to the shogunate.

Shōzan is best remembered for his slogan "Eastern ethics and Western technique" (和魂洋才). After studying Western technology and science and comparing it with Neo-Confucianism (朱子学 shushigaku), he concluded that while they were both indispensable aspects of human knowledge, the spiritual element, Eastern ethics, was the more venerable. His belief thus heralded the transformation of Japan into a modern nation, based on the blending of the old and new, of the East and West.


  • Earl, David Magarey; Emperor and Nation in Japan: Political Thinkers of the Tokugawa Period, Praeger 1981
  • Feifer, George; Breaking Open Japan: Commodore Perry, Lord Abe, and American Imperialism in 1853, Smithsonian 2006
  • Jansen, Marius B.; Sakamoto Ryoma and the Meiji Restoration , Columbia University Press 1995
  • Jansen, Marius B.; The Making of Modern Japan, Cambridge 2002
  • Reitan, Richard M.; Making a Moral Society: Ethics and the State in Meiji Japan, University of Hawaii Press 2009

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