Is it a book about justice, as the subtitle of the book suggests?

这是本有关正义的书籍吗，就如子标所暗示；

耶鲁公开课 - 政治哲学导论课程节选

It was practical books about fortifications, hydraulics, artillery, navigation, and shipbuilding.

而是实际的书籍,比如有关防御工事的,水力学,炮术,航海和造船的

耶鲁公开课 - 欧洲文明课程节选