  William replies that Avicenna's principle leads to an infinite regress; for if something's operating after not operating requires a change in it, this change will itself require a new cause, and that new cause will itself require a new cause, and so on ad infinitum. William instead holds that it is possible that God, without changing in any way, start to operate after not operating. What William means by this is that the effect of God's eternal will is a world with a temporal beginning. In general, he holds that verbs such as “create” express nothing in the creator himself but rather something in things. We might put “God begins to create the world” to have the import of: “God by an eternal willing creates the world, and the world has a beginning.”