In fact,the legend about spreading a poisonous spiritual force which results from their ignorance of infectious diseases is a superstitious way of saying.

The Miao′s belief in fanggu is one of the cultural phenomenons that have been affecting the life of the Miao area for a long time.

There was a character of "Gu" in inscriptions on bones or tortoise shells of the Yin-Shang Dynasty,which shows that,three thousand years ago,people had found the animals that live in the human body.

In dealing with advancing or withdrawing, entering society or being a recluse, hexagrams Gu (Arresting Decay, the 18th hexagram in the received version of Zhouyi) and Dun (Retreat, the 33rd hexagram) advocate a eremite life.

The controversies about "venomous worm of witchcraft" reveal the ways of imagining and constructing other based on self-centrality and the separation from the neighborhood.

Oracular shells excavated at Zhouyuan and the hexagram of Gu in Zhouyi;

And Gu Du(poison) is the most mysterious portion of black withcrafts in Songs folk culture and causes a great disaster in peopless social lives.