Kogi Shoji was born in Arita, Hizen Province (Saga Prefecture), in the family of a wealthy merchant.
Fond of learning since childhood, especially of practical economy.
Contrary to many scholars of the time who favored a feudalistic economic system divorced from the rest of the world, Kogi insisted the necessity of foreign trade. Lamenting that the traffic system of Japan was kept in an inconvenient state for military reason, he proposed that roads be improved. He believed that inequality is a law of nature and that the artificial control of usury entails no good effect.
Kogi Shoji developed a large acreage of wasteland by employing many peasants. Although his beliefs were sometimes contradictory, he was the best bourgeois economist of the time, as against Nobuhiro Sato, who was a sort of national socialist.