A translation of two books on the philosophy of the Itto School of Sword Fighting. Book 1: The Twelve Rules of the Sword. Book 2: The Sword Manual of Kanamaki Jizai. The first is attributed to Ito Ittosai the legendary swordsman of the 16th century. Ittosai travelled the country and fought the head students of 33 schools, winning every time. The second is a 16th century instruction manual attributed to Ittosai's teacher Kanamaki Jizai. These books are essential for understanding the development of traditional Japanese sword arts and Kendo.