Ruqing (, 1803-1887), also wrote on the topic after they retired from government service, though those works along with more by Li Yiyu were not made public until the 1980s and 1990s, so have been called "lost classics". Wu likely also shared his writings with Yang Luchan, and with Yang's son Yang Banhou (, 1837-1890) who Wu tutored (probably in literacy as well as t'ai chi). Although the Wu and Yang lineages appear to have drifted apart by the next generation, in the early twentieth century Yang Chengfu's disciples began to publish their own versions of these texts with their own additions, and began to call them the "T'ai Chi Ch'üan Classics". The Name of T'ai Chi Ch'üan The name "t'ai chi ch'üan" (Pinyin: tàijíquán) may have first appeared in the Wu/Li family's mid-nineteenth century writings, perhaps drawn from the Wang Zongyue text which begins with the words "Taiji is born from Wuji; it is the mother of Yin and Yang". As the Wu family had no need to promote their art, it was left to the Yangs to bring this to the public first. But with different priorities, especially as the two families drifted apart (or worse) by the second generation, they often felt no need to mention each other at all which is why few knew of this. Yang family tradition tells us only that imperial court scholar Weng Tonghe (Ong Tong) used the term "t'ai chi" in a poem describing a performance by Yang Luchan. It is not clear if that was an additional influence on the name, or if the new name was already in use there, along with the earlier names "Thirteen Postures" (), "Long Boxing"(), and "Soft/Cotton/Neutralizing Boxing" (). Written evidence for Yang family adoption of the name "T'ai-chi" first appeared in a later text, possibly completed in 1875 by Yang Luchan's son Yang Banhou (who had been tutored by Wu Yuxiang), or no later than the first decade of the twentieth century by one or more of Banhou's Yang or Wu () disciples. By the second decade of the twentieth century, Yang Chengfu disciples and Sun Lutang were using the term "t'ai chi ch'üan" in their publications, including in the titles of some of the T'ai Chi Ch'üan Classics. It then appeared in a book by a Chen family member, Chen Xin, published after he died in 1929. This timeline may represent the