In the Earthly Branches, there are four special symbols. They are called Four Burial(四墓库) . The Four Burial Stages of the earthly branches are Chen, Xu, Chou and Wei(辰戌丑未).

Why are they special? Where are they special?

This question will never be answered unless you really understand LuMing’s model, but those “masters” you see on the Internet don’t understand at all.

What is “LuMng Model”?

You need to understand the movement track of the sun and the moon in a year, and connect the symbol of LuMing with them to really understand. They are astrology.

Now what you only need to know is that these four symbols(辰戌丑未) are special. They contain other energies. Once the conditions are mature(6Clash, 3Harms), these energies will be released, resulting in major changes in the energy of the original four pillars.

辰Chen: A lot of Water Energy hidden in it

戌Xu: A lot of Fire Energy hidden in it

丑Chou: A lot of Metal Energy hidden in it

未Wei: A lot of Wood Energy hidden in it

Note that when the conditions are not mature, they only represent Earth. When the conditions are mature, a lot of different energies will be released. 

These conditions include 6Clash, 3Harms. About the relationship you need to understand this article: https://www.rethealth.com/4941.html

For example:

The Four Pillarss of a chart contain 辰Chen. Maybe the MC is 辰Chen. The year comes to 2018, we know 2018 is 戊戌WuXu, then 戌 clash MC辰, the energy is about to be released.

Is the energy of water released? Or is the energy of fire released? Or are they released together?

That is a difficult point, usually only one kind is released, now we need to judge whether there are 壬Ren and 癸Gui on the original Four Pillars? If yes, the energy of Water will be released and the Fire will be extinguished. Breaking the balance will have consequences. If the Four Pillars contain a large amount of 丙丁巳午, Then the energy of Fire will be released and the energy of Water will disappear. It will also have an impact.

This is the principle of judgment.