The heavenly stem is the yang stem, and when you see the yang stem, you are the god of food. When you see the yin stem, you are the wounding official. (Jia, Bing, Wu, Geng, and Ren are the yang stems; B, Ding, Ji, Xin, and Gui are the yin stems.) For example: Jia wood is the yen, Bing fire is the god of food, and Ding fire is the wounded official. If Yi wood is the sun In Yuan, Ding fire is the god of food and Bing fire is the wounded official.