to its history and the particular training insights of master teachers. Currently, the subdivisions of Chen style Taijiquan include: Historical training methods from Chen Village; forms derived from the lineage of Chen Fake commonly known as Big, or Large, Frame: Old Frame and New Frame; Chen family Small Frame; training methods from Chen Fake's students, such as Tian Xiuchen, Feng Zhiqiang and Hong Junsheng; and closely related traditions, such as Zhaobao Taijiquan (趙堡太極拳). In the past, the efficacy of a training method was determined through actual combat. In the modern era, such tests of skill no longer take place. There also are no recognized central authorities for Taijiquan. This led to the determination of authenticity for any style depending on anecdotal stories or appeal to historical lineage. Chen Taijiquan also follows this trend for the most part. The Chen style practitioner, however, follows a more stringent requirement. According to Chen Fake (1887-1957), the last great proponent of the Chen style in the modern era, the external appearance of the form is not important. Each movement is based on intricate theories unique to this system. A correct Chen style Taijiquan form should be based on the same fundamental principle and each element of a form should have a purpose. In Chen Fake's words: "This set of Taijiquan does not have one technique which is useless. Everything was carefully designed for a purpose." ("这套拳没有一个 动作是空的, 都是有用的") The understanding of each subdivision should be interpreted with these ideas in mind. The fundamental principles for Chen style taijiquan are summarized as follows: Keep the head suspended from above (虚领顶劲, xū lǐng dǐng jìn) Keep the body centered and upright (立身中正, lìshēn zhōngzhèng) Loosen the shoulders and sink the elbows (松肩沉肘, sōng jiān chén zhǒu) Hollow the chest and settle the waist (含胸塌腰, hán xiōng tā yāo) Drop the heart/mind energy [to the dantian] (心气下降, xīn qì xià jiàng) Breathe naturally (呼吸自然, hū xī zì rán) Loosen the hips and keep the knees bent (松胯屈膝, sōng kuà qū xī) The crotch is arch shaped (裆劲开圆, dāng jìn kāi yuán) Empty and solid separate clearly (虚实分明, xū shí fēn míng) The top and bottom coordinate (上下相随. shàng xià xiāng suí) Hardness and softness facilitate each other (刚柔相济, gāng róu xiāng jì) Fast and slow alternate (快慢相间, (kuài màn xiāng jiàn) The external shape travels a curve; (外形走弧线, wài xíng zǒu hú xiàn) The internal energy travels