The 16th century Chinese fight book Jian Jing 劍經 (Sword Treatise), written by the Ming dynasty (1368–1644) general Yu Dayou 俞大猷, is the oldest available comprehensive work on Chinese fencing theory. This paper argues that the treatise uses the terms gang 剛 (hard) and rou 柔 (soft) as technical terms to label tactics what are known as first and second intention offence in modern sport fencing. The terms hard and soft became widely used from the late 17th century onward by practitioners of the so-called ‘internal schools’. Since then the terms hard and soft have remained part of Chinese martial arts vocabulary.