Watch your little brother lose it laughing at a cartoon. Joy that cheap is worth paying attention to.

Joy that costs nothing is worth studying, because the price goes up as you get older. A seven-year-old can be destroyed by a cartoon, fully and physically, over something you would describe as not even funny. Sophistication raises the entry fee for being delighted, and nobody warns you that the raise is permanent unless you work against it.

Sit down and watch the stupid thing with him this week. Let yourself laugh at the level it deserves rather than the level you think suits you now.