When he was fourteen, he started to go to purchase indigo plants by himself, which created the foundation on which he could easily absorb economic systems in the Europe era and later brought about his thoughts of realistic rationalism.
14歳の時からは単身で藍葉の仕入れに出かけるようになり、この時の経験がヨーロッパ時代の経済システムを吸収しやすい素地を作り出し、後の現実的な合理主義思想につながったとされる。