The Golden Elixir

① Yin (Tiger) and Yang (Dragon).

The Dragon is Yang, its number is odd, the Tiger is Yin, its number is even. 龍陽數奇，虎陰數偶。

② Two emblems of the agents Wood and Metal. The Dragon is associated with Wood (East, Yang), the Tiger is associated with Metal (West, Yin). (These are the ordinary associations based on the system of the five agents.)

The Tiger is the Metal of the West. … The Dragon is the Wood of the East. 虎，西方金也。… 龍，東方木也。

③ Body and mind.

Body and mind are represented by the Dragon and the Tiger. 以身心喻之龍虎。

④ Lead and Mercury.

Lead is the one particle of True Yang within Kan ☵; we call it Dragon. Mercury is the one particle of True Yin within Li ☲; we call it Tiger. 鉛者、坎中一點真陽、謂之龍也。汞者、離中一點真陰、謂之虎也。

⑤ In Li Daochun’s exposition of Neidan, a term understood in different ways according to different levels of Neidan. ⓐ Nature (xing) and emotions (qing). ⓑ Body and mind. ⓒ Liver and lungs.

In the higher vehicle, Dragon and Tiger are Nature and emotions. … In the middle vehicle, Dragon and Tiger are body and mind. … In the lower vehicle, Dragon and Tiger are liver and lungs. 〔上乘者，以〕性情為龍虎。… 〔中乘者，以〕身心為龍虎。… 〔下乘者，以〕肝肺為龍虎。