change. We can clearly see that some things in the world are in the process of change, and this change must be a result of something else, since a thing cannot change of itself. But the cause of the change itself, since in the process of change, must also be caused to change by something other than itself, and so on again, ad infinitum. Clearly, there must be something which is the cause of all change, but which itself does not undergo change. For, as Aquinas says, ‘if the hand does not move the stick, the stick will not move anything else’. The first mover, Aquinas concludes, is God.

