I am interested to study the historical exchanges between Taoist sages and Tantric Buddhists in the Western China- Tibetan region. We have some idea about the interaction of Chan sects and Tibetan Mahayana since the time of the great Samye debate, but I am yet to read the interaction between Tibetan Tantrics and Taoist priests in history. I was reading about how Fahai Lama, a Chinese Dzogchen master, gave Tantric initiations and teachings to his master Huiding, who was also a discple of the famous Hsu Yun. I was surprised to read that Huiding was not aware of the central channel of the human body and the four "chakras" (to use a Buddhist terminology; also called Dantien in Chinese), which I thought was pretty common knowledge among the Chinese Taoists, physicians and even martial artists. I had thought that accomplished masters of Mahayana and even Theravada sects had automatic insight about these things due to their deep meditative experience. Even if the non-Tantric Buddhist masters are not aware of the energy body, it is still quite understandable, but Taoism is full of all these practices. So I am now interested to know about the interaction, and possibly influences and exchanges, between Taoist priests and Tantric Buddhists in China.