Born in 1782 as the eldest son of the wealthy merchant Hakataya in Hita in Bungo Province (today Hita, Oita). Brilliant at learning from an early age but of frail health, he did not take over the family business and devoted himself to scholarship. He studied under Kamei Nanmei and his son Shoyo in Fukuoka, and after returning home, in 1805 at age 23, opened the 'Seishosha.' In 1807 he opened 'Keirin-en,' and in 1817 opened 'Kangien' at its present site. The name 'Kangien,' meaning 'all alike good,' is drawn from the Classic of Poetry and symbolizes the open-door principle of welcoming anyone to study regardless of origin, age, or prior learning. Its hallmarks were the 'three-strippings rule' (on entry, one's origin, age, and prior learning were not asked) and the 'monthly evaluation' (ranking by monthly assessments). Over eighty years, more than 4,800 students gathered from across the country, producing disciples from as far east as Mutsu to as far west as Satsuma. Takano Choei, Omura Masujiro, and Cho Sanshu were among his pupils. He died in 1856 at the age of 75. Using the pen name 'Enshi,' he was also an excellent poet and left the collection 'Enshiro Shisho.'

An educator of frail health but warm temperament, strict in etiquette. Seeing through each student's individuality, he held fast to a method that nurtured their strong points. Combining severity with warm feeling, he was respectfully loved as 'Master Tanso.' A humble man of practice who refused official posts and gave his life to education. As a poet too he excelled, eagerly teaching his students the craft of Chinese verse, and the exchange of poems colored the daily life of the academy.

Kangien continued for eighty years until its closure in 1897, and with more than 4,800 students in all, it was one of the largest private schools in the world at the time. It produced talent in politics, the military, and scholarship — Takano Choei, Omura Masujiro, Cho Sanshu, Kiyoura Keigo (later prime minister), Ueno Hikoma (the photographer). In 2015 it was designated a Japanese national heritage site as part of the 'Group of Educational Heritage Sites of Early Modern Japan.' The Kangien Education Research Center now stands on the site, and Tanso's educational thought is being reevaluated as carrying a message that speaks also to today's lifelong learning and education for diversity.