Well, it's when grownups ask, What are you going to do? And you say, Nothing. Then you go out and do it.
10 seconds sound clip from the The Many Adventures of Winnie the Pooh movie soundboard.
You can hear this line at 01:12:41 in the Blu-ray version of the movie.
Quote context
[...]
- And where a place called Brazil is.
- What do you like doing best in the world?
- What I like best is me going to visit you, and you saying, How about a smackerel of honey?
- I like that, too. But what I like best is just doing nothing.
- I like that. Let's do it all the time.
- You know something, I'm not going to do just nothing any more.
- When I'm away just doing nothing, will you come up here sometimes?
[...]