The text emphasizes Jihi no Kokoro , or the "benevolent heart," arguing that true Ninjutsu is about finding harmony and protecting the spiritual and natural worlds rather than mere assassination.
Hatsumi traces the lineage of the shinobi from the 12th-century Nanboku-chō period through their peak during the Sengoku Jidai (Warring States period). Ninjutsu, history and tradition
Masaaki Hatsumi’s (1981) remains a foundational text for anyone looking to separate historical fact from the cinematic myth of the ninja. As the 34th-generation leader of the Togakure-ryū tradition, Hatsumi provides a unique perspective that treats Ninjutsu not just as a combat system, but as a comprehensive philosophy for survival and spiritual development. A Bridge Between Two Eras The text emphasizes Jihi no Kokoro , or