>> Tai chi is an internal Chinese martial art practiced for both its defense training and its health benefits

Tai chi is an internal Chinese martial art practiced for both its defense training and its health benefits. Though originally conceived as a martial art, it is also typically practiced for a variety of other personal reasons: competitive wrestling in the format of pushing hands (tui shou), demonstration competitions, and achieving greater longevity. As a result, a multitude of training forms exist, both traditional and modern, which correspond to those aims with differing emphasis. Some training forms of t'ai chi ch'uan are especially known for being practiced with relatively slow movements.

Today, t'ai chi ch'uan has spread worldwide. Most modern styles of t'ai chi ch'uan trace their development to at least one of the five traditional schools: Chen, Yang, Wu (Hao), Wu, and Sun. All of the former, in turn, trace their historical origins to Chen Village.

Yang Chengfu in a posture from the Yang-style t'ai chi ch'uan solo form known as Single Whip c. 1931

From a modern historical perspective, when tracing t'ai chi ch'uan's formative influences to Taoist and Buddhist monasteries, there seems little more to go on than legendary tales. Nevertheless, some traditional schools claim that t'ai chi ch'uan has a practical connection to and dependence upon the theories of Song dynasty Neo-Confucianism (a conscious synthesis of Taoist, Buddhist, and Confucian traditions, especially the teachings of Mencius). These schools believe that t'ai chi ch'uan's theories and practice were formulated by the Taoist monk Zhang Sanfeng in the 12th century, at about the same time that the principles of the Neo-Confucian school were making themselves felt in Chinese intellectual life.

However, modern research casts serious doubts on the validity of those claims, pointing out that a 17th-century piece called "Epitaph for Wang Zhengnan" (1669), composed by Huang Zongxi (1610–1695 A.D.), is the earliest reference indicating any connection between Zhang Sanfeng and martial arts whatsoever, and must not be taken literally but must be understood as a political metaphor instead. Claims of connections between t'ai chi ch'uan and Zhang Sanfeng appeared no earlier than the 19th century.

Painting in Chenjiagou, illustrating taolu according to the Chen style of taijiquan.

History records that Yang Luchan trained with the Chen family for 18 years before he started to teach the art in Beijing, which strongly suggests that his art was based on, or heavily influenced by, the Chen family art. The Chen family are able to trace the development of their art back to Chen Wangting in the 17th century. Martial arts historian Xu Zhen believed that the Taiji of Chen Village had been influenced by the Taizu changquan style practiced at the nearby Shaolin Monastery, while Tang Hao thought it was derived from a treatise by the Ming dynasty general Qi Jiguang, Jixiao Xinshu (New Treatise on Military Efficiency), which discussed several martial arts styles including Taizu changquan.

What is now known as "t'ai chi ch'uan" appears to have received this appellation from only around the mid-1800s. A scholar in the Imperial Court by the name of Ong Tong He witnessed a demonstration by Yang Luchan at a time before Yang had established his reputation as a teacher. Afterwards Ong wrote: "Hands holding Taiji shakes the whole world, a chest containing ultimate skill defeats a gathering of heroes." Before this time the art may have had a number of different names, and appears to have been generically described by outsiders as zhan quan (沾拳, "touch boxing"), Mian Quan ("soft boxing") or shisan shi (十三式, "the thirteen techniques").
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