The samurai warrior remains an enduring symbol of Japan. In the 17th century, when peace came to the country after more than a century of wars and turmoil, samurai continued to practice their sword-wielding skills, with emphasis shifting from the demands of the battlefield to ideals of self-cultivation. With expert Alex Bennett, we examine the philosophy of influential swordsman Yagyu Munenori, who popularized swordsmanship as a means of cleansing one's heart and achieving one's full potential.