I nearly died of pneumonia under rather strange circumstances when I was 12. It left me with the utter conviction that I was mortal - a notion that most adolescents are lucky enough to lack.

Rather than being unable to imagine that I would ever die, I was unable to imagine that I would make it to middle age. Naturally, I had some fairly dramatic ideas about being doomed and dying young.

Talk about cognitive dissonance! This year I turned 40 and survived cancer. I'm an old fartress, which just goes to show how mistaken I can be.