3. Yin, Yang, Qi and Five-element Theories

The ancient Chinese perception of five elements, which give rise to all forms of matter, included metal 6 (jin), wood (mu), water (shui), fire (huo) and earth (di). It was thought that these elements successively produce and destroy each other, thereby causing the physial and chemical transformations, e.g., earth generates metal metal generates water and water generates wood wood generates fire fire generates earth. 'jin jin metal mu mu wood shui shui water huo huo - fire di tu earth

Likewise, earth destroys water water destroys fire fire destroys metal metal destroys wood and wood destroys earth. Much is written about the theory of Yin and Yang as well as the five-elements in relation to the processes of alchemy. The theory of Yin and Yang is beautifully 7 explained by Ho Peng-yoke in the following way. - - The pneumatic concept of the Greeks had its parallel in China. The universe was filled up with qi, whose state of rest and motion give rise to the two cosmological forces Yin and Yang. From these two forces were derived four different "phases" water, when the qi had already been at rest for a maximum period i.e. when Yin had reached the highest point, metal when the qi of Yin just entered a state of rest; wood and fire when the qi of Yang had reached its maximum state of motion. These four "phases" congealed in different proportions giving rise to the earth "phase" which gave the material forms of all matter. The qi above the earth changed cyclically, according to the seasons. This could alter the proportions of the different "phases" in the composition, say of a metal, resulting in transmutations. However, this natural transmutation would take time, at least a few hundred years, too long for mortals to wait. Chinese alchemists believed that ways and means could be found in their laboratories to hasten this process. The Chinese alchemists divide substances into Yin and Yang categories. Yin represents every thing that is cool, feminine and Yang, hot and masculine. 7. Ho Peng-yoke, "Final Curtain on Chinese Alchemy", unpublished manuscript. 51