In the first year of the college, a Japanese law professor wrote a book title, "Der Kampf um's Recht," on the blackboard. It was one of my favorite books in the high school days. He asked who knew the book title. Anybody in the class of six hundreds or more said nothing to him and I said to him, "It's Jhering's." He asked me for its Japanese translation and I replied it to him.
Before entering the law college in Japan, I was familiar with legal treatises published in Germany. Among them, von Jhering's were the best to me. "Der Kampf um's Recht" means "The Struggle for Law." That is the golden rule in the world, for ever.