If given an unambiguous test, prayer invariably fails. The best-known example is to pray for a fair coin to land heads thirty times consecutively. The chance of this happening is about one in a billion. If God wanted to though, He could easily arrange the run. Yet the prayer has no effect – even when the salvation of an individual is at stake, which is a fairly strong motivation for God to intervene.

America has a very large population of christians, many of whome pray for the country on a regular basis. Yet the country still suffered the 911 attacks. Un-christian ideas continue to make headway in politics. Democrats still regained a majority in both houses, albeit very slim. The US forces in Iraq continue to take losses and struggle. Abortion remains legal. So what, exactly, has all the praying in the past done? As it appears to have failed at achieving the objectives of those doing the praying, is there any reason to suppose that more prayer in future should have any greater effect?

In some ways, prayer is like any other superstition. People continue to avoid walking under ladders, to touch wood, to hang horseshoes… even though these, like prayer, have no impact.