He went to Edo at the age of 16 to learn more about agriculture. In Edo he studied Dutch and pharmacology under Genzui Udagawa and astronomy, geography, zoology, botany, calendar science and surveying under Taizo Kimura and Shoei Yamamura and other scholars.
In 1785, he followed Genzui to Tsuyama (Okayama Prefecture), where he wrote Kaikakuki (On Reform) and dedicated it I to the lord of Tsuyama.
In 1791, he went to Nagasaki, stayed there one year and then toured other parts of Kyushu, giving advice to lords on the administration of their domains. He returned to Edo (1795) and practiced medicine. He became an adviser to Lord Kano of Ichinomiya in Kazusa Province (Chiba Prefecture) at the latter's request and made recommendations on promotion of the local fisheries.
Returned to Edo and again practiced medicine. Became the Awa Clan's (Tokushima Prefecture) teacher of gunnery and Western military science at a time when Russian activities in the north awakened the nation to the need of coastal defense. Although he became famous for his learning, he often offended the government because of his outspokenness.
Satō advocated an authoritarian government based on Western science and political institutions. In his Keizai yōryaku (The Epitome of Economy), he wrote that "The rationale of economy is to manage the realm, develop goods, make domains affluent, and succor everyone."