Here It Is

Christmas descends. I felt it come down on us yesterday. Like a fall of invisible snow. There's a new quality to the silence. As if the world had caught its breath. As if TinyTim's muffler had been wrapped round ears and mouth. We have entered the zone of ever so slightly altered reality. It's a one way tunnel of a certain length with no side exits.  

How And Why?

You put a lot of washing in the washing machine and one of the items is a duvet case. You take it out again after running the programme and find that all the smaller things have managed to get themselves inside the case. How does that happen?

It's not as if it were a fluke. It happens time and time again. There must be some scientific principle at work.