I have heard Christadelphians assert that our prayers are answered in one of three ways; 'Yes', 'No' or 'Not yet'. I think this is an interesting manoeuvre for two reasons. Firstly, because it means that there is no evidence that can possibly be used to falsify this assertion - as a 'truth proposition' it is impossible to verify. And secondly, because if prayer didn't work we would expect to see these exact same outcomes. If the natural course of events were to play out then these are the only three possible options available.