Let me relate to you a dialogue I once overheard.
Picture two children. One of them -- "Ray" I think his name was -- was visibly distressed by the revelation that his brother Brian no longer believed in Father Christmas.
- But you must believe! How can you not believe?
- Ray, don't you see it? There is no Father Christmas. It's just a fantasy!
- Well, if there's no Father Christmas, who gave you that shiny new Game Kit last Christmas?
- It says "Made in Taiwan" on the Kit. I don't think it came from the North Pole. You know, I snuck a peek into papa's wallet, and there was a receipt for a Game Kit. It's our parents who are giving us those presents.
- Well maybe Father Christmas put the receipt there! He's testing our faith!