A small hand reaches up, and an eager smile appears: “I wanna-pay-wit dat pussle.” From the drawer indicated, the brown puzzle pieces are retrieved, then laid flat upon the carpet. The not-yet-three-year-old sets about his task with the words “I make a diamond.” The “diamond” is a regular heptagon, and the set makes a pair of heptagons, so the dad helps his son divide up the pieces and get started. With some coaching, the son forms first one, and then the other, of the heptagons. Finally, the dad takes his turn, assembling the whole set into a 7-pointed star, with a little help from his son. Repeated many times already, this activity has transcended puzzle into ritual – a ritual that echoes the dad's creation of the puzzle two decades earlier.