the sticking and thrusting pole practice of the Yang and Chen styles, but without the many rotations of Chen-style spear forms. These forms share many other similarities with Yang-style weapons forms, and may be closely related. In some Hao family schools the straight sword form is almost exactly the same as the Yang-style version. In the Li family lineage, although their straight sword form is a different sequence, their two-person saber set is quite similar to a set practiced by some Yang-style branches and may be related via Yang Banhou. This is worthy of more research. Partner work includes stationary and stepping push hands (, tuīshǒu), as well as freestyle grappling (, sàndǎ). Further discussion of push hands theory is in the Comparisons section below. As mentioned above there are also two-person weapons sets for saber and staff. The 13 Important Points The T'ai Chi Classics of the Wu (Hao) style include a list of thirteen important points for every practitioner to keep in mind. Wu Yuxiang compiled the first eight, the "body methods" (, shēnfǎ), while Li Yiyu added the final five "essentials" (, Simplified , yāolǐng). All Wu (Hao) lineages agree on the importance of this list for each and every movement, though some list them in a slightly different order. Following is a translation of the list as taught by Liu Jishun, grandmaster of the Hao family lineage. Comparisons: Chen and Yang (and the origin of Kai He) Wu (Hao)-style t'ai chi is based on principles shared with other styles, especially Yang style. For example, Yang Chengfu's "Ten Essential Points" are quite similar to the Wu (Hao)-style "Thirteen Important Points" listed above, and in fact Wu Yuxiang has been named as the source of the Yang essential points list by some writers in the Yang-style lineage. Chen-style masters also teach these essentials with a few additional points, most notably the concept of internal spiral energy paths. Like Yang-style, Wu (Hao)-style focuses on "pulling silk" (, , chōusījìn) rather than the Chen-style "reeling silk" (, , chánsījìn), and Wu (Hao) shares with Yang the focus on "sinking qi to the dantian" (, ) rather than the Chen emphasis on dantian rotation (, ). But all t'ai chi styles contain all of these principles, varied only by emphasis. Other points of comparison include the many posture names and sequences in the empty-hand forms that are shared with Yang style