Escaping danger is undoubtedly the safest art of self-defense, and Yukichi supposedly regarded Iai as entirely a way of seeking after truth and not a way of killing a person, which is close to the ideas of Kaishu KATSU and Tesshu YAMAOKA, who had also never killed a person, although they had a reputation for their mastery of swordsmanship.
無論、逃げる事は最も安全な護身術であるが、福澤自身、居合はあくまでも求道の手段であり殺人術でないと考えていたと思われ、同じく剣の達人と言われながら生涯人を斬ったことが無かった勝海舟・山岡鉄舟の思想と似ている。