The draft of Family Law in Civil Law during the Meiji period was close to Yukichi's theory of the equality of the sexes, and Yukichi supported the draft, but it was replaced by Family Law adopting patriarchy because the draft was opposed by the descendants of samurai families.
なお、明治民法の家族法の草案段階は、福澤の男女同等論に近いものであったり彼もそれを支持したが、士族系の反対があったため父家長制のものに書き換えられた。