A history question! ! !

Mozi was going to Qi State in the north, and he met a divination wizard. The wizard said, "The Emperor of Heaven is going to the north to kill the black dragon today. Mr. Wang's skin is the same color as the black dragon. I said you should never go to the north. " Mozi didn't listen to him and kept going north. When we got to Zishui, we couldn't cross the river, so we had to go back. The wizard saw Mozi and said, "I told you not to go north." Mozi said: "As you said, southerners can't go to the north, northerners can't go to the south, and people's skin color is black and white. Why can't they walk around? " Besides, the Emperor of Heaven killed Qinglong in the north yesterday, Red Dragon in the south today, White Dragon in the west tomorrow and Black Dragon the day after tomorrow. If you follow your advice, people in the world will be forbidden to walk. This not only goes against people's hearts, but also makes the world empty. You can't listen! "