In Chinese traditional system of five elements, there are (at least) three possible angles of comprehension or interpretation: firstly conceptual, secondly physical or spacial and thirdly temporal.
Conceptually speaking, five elements (metal, water, wood, fire and earth) represent the fundamental elements forming everything. This is an intuitive understanding of formation. In our modern scientific paradigm, the periodic table (chemical elements) forms a more comprehensive/complex system of understanding. The question is: what is the purpose of trying to understanding our world, in the first place, through five elements, and in the second place, through our current periodic table?
In traditional Chinese culture, five elements forming a mythical/spiritual system through which man can understand almost every aspects of his surrounding: including both physical and spiritual aspects of man. A modern periodic table's ambition becomes very modest by comparison!
Fair to say, most modern Chinese can get along their lives very well without consideration of the five elements. This system has become more spiritual, for specific people, rather than physical. Even the usage of five elements in modern Chinese medicine is symbolic rather than actual (Knowledgeable readers might not agree with me here. I shall discuss its relation to Chinese medicine in a future post).
Another important conceptual understanding of five elements is the famous Facilitative (相生) and Destructive (相克) influences that I discussed at a previous post: The mysterious five elements and I-Ching. And these two influence also cover the temporal interpretation of five elements.
How about physical interpretation? Traditionally five elements can be interpreted physically as positions of North, South, East, West and Center. Probably with an intention to mystify (nowadays we have a term for it: "barrier to entry", aiming at those interested to become professionals in the discipline!), North is equal to map-South (i.e. true North), South to true-North, East to true-West and West to true-East! Center, fortunately, remains the same. Schematically it can be represented as follows:
According to prominent scholar Nan Huai-jin (南懷僅), in his Essays on I-Ching (易經雜說), the physical positions of the five elements are based on the geographic position of China as perceived by ancient Chinese: Center being China, with North signified by water as snow, South signified by fire as sun's heat, East signified by wood as plantation, and West signified by metal as mining. Assuming Nan is right, then the interesting point becomes: a simple descriptive interpretation of the five elements had later become the foundation of an influence practice of Feng Shui(風水). The issue as to the true nature of this practice (psycho-therapeutic, spiritual or superstitious) depends on each person's own choice and/or belief system.
If this is not complicated enough, one should note that each physical position is further divided into two positions: Yang （陽) or Yin (陰), each symbolized by one of the ten Heaven Stems!(5 [elements] x 2 [Yin/Yang] = 10 positions) One should note that as a symbolic system the mapping of five elements and the heaven stems is purely arbitrary (with "barrier to entry" overshadowing everything). Its later mystical interpretation and mystical power associated with it is one "application" of the purely symbolic five elements system.
Note: 天干 The Heavenly Stems
甲 the first of the ten Heavenly Stems
乙 the second of the ten Heavenly Stems
丙 the second of the ten Heavenly Stems
丁 the third of the ten Heavenly Stems
戊 the fifth of the ten Heavenly Stems
己 the sixth of the ten Heavenly Stems
庚 the seventh of the ten Heavenly Stems
辛 the eighth of the ten Heavenly Stems
壬 the ninth of the ten Heavenly Stems
癸 the last of the ten Heavenly Stems