The founders of the Zhōu dynasty believed in the idea that King Wen, the father of King Wu (who was the first to actually rule after the Shàng rulers were defeated), continued to be able to act in the world of human beings even after his death. He and his own father and grandfather were central figures in an important document called "The Brass-bound Coffer." Another important document is called "The Announcement of Duke Shao." Both of these documents introduce and support the idea that Tiān decides who will be the human to act as steward or helper to carry out the will of Tiān on earth, and the idea that Tiān will only let someone be king as long as he looks out for the welfare of all human beings.