It is one of my earliest childhood memories. I am about five years old, seated on a normal (adult) chair at a wooden table, the edge of the table barely under my chin. On the table is a plastic cup, lying on its side. Around the cup is a large puddle of milk, which, given the table's slight incline, is dripping off the right-hand side of the table onto the white linoleum floor. There is nobody else in the room.

I stare at the cup in fascinated terror. For it was me who knocked the cup over. And my mother would be returning in a moment and she would know I did it. She's too clever, our mum, she knows cups don't spill themselves, she knows birds can't fly in through closed windows to tip cups over, she would not have felt the earthquake that shook the table, cup and milk.