Born into a samurai family of the Kumamoto domain in Higo.
He went to study in Edo and associated with Fujita Tōko of Mito and others.
Around this time he opened a school in Kumamoto, teaching jitsugaku, practical learning useful to society.
Invited by Matsudaira Shungaku, lord of Fukui, he became adviser on domain government.
He wrote Kokuze Sanron, setting out how to enrich the country, strengthen its defence and govern well.
When Shungaku took high shogunate office, he assisted him in reforming shogunate government.
Blamed for fleeing an attack, he was stripped of samurai status and lived quietly in Kumamoto, where Sakamoto Ryōma and others visited him.
He was invited into the new Meiji government in an important post.
In Kyoto he was attacked by samurai opposed to opening the country and lost his life.
Sakamoto RyōmaSatō IssaiMatsudaira Shungaku (Yoshinaga)Yuri KimimasaInoue KowashiFujita Toko
Takano ChōeiTownsend HarrisFujita TokoShimazu NariakiraOgata KōanHotta MasayoshiSakuma ShōzanIi Naosuke
People of the Edo period ・ People by period
Based on facts found in textbooks and biographies. Uncertain points are marked as such.