Mao Collection, Upper Volume Radical: Heart (xīn) 愫 Kangxi Strokes: 14 Page 396, Entry 12 Gathering of Rhymes (Jiyun), Collected Rhymes (Yunhui), Standard Rhymes (Zhengyun): Pronounced su. Gathering of Rhymes (Jiyun): Sincerity. Collected Rhymes (Yunhui): True feelings. Collection of Characters (Zihui): Genuine emotional state. History of the Former Han (Qian Han Shu), Biography of Zou Yang: To reveal one's heart and expose one's true feelings (qing su). Commonly written as the variant form (su).