1. I have heard there are differences among human beings endowed with yin or yang. What about those with yin character, and those of yang personality?
2. Everything in the world,in the whole universe,can be divided and sorted according to the theory of Five Elements.
3. The sorting of people is also part of this principle. But there is no absolute division between yin and yang. The yin and yang is only the simplest and most direct way of ex pressing the principle.
4. Why? The boy is not usually so rude.
5. Natural endowments are too complicated to be explained with a few words.
More information, please read Inter-Rejection of Yin and Yang.