There's nothing more contagious than the laughter of young children; it doesn't even have to matter what they're laughing about.
The best ideas will eat at you for days, maybe even weeks, until something, some incident, some impulse, triggers you to finally express them.
Closed in a room, my imagination becomes the universe, and the rest of the world is missing out.
Everyone has a sense of humor. If you don't laugh at jokes, you probably laugh at opinions.