It is one of those weird social things. Even as parents we say, oh, don't be sad. You know, come here, we'll distract you with some ice cream or something. And I don't know if that's always the best thing. But it's certainly - you understand why people do it.

I knew that there was an upcoming screening where not only were we going to show it to everybody else at the studio, we also needed to move into production... And yet I was sitting there in editorial going this is not working. I'm a failure.

But the truth is, at some point, our films - almost every single one of them - are really bad. And it's largely hats off to John Lasseter and Ed Catmull who have set up a system whereby they're expecting it.

We found some scientists think that there are basically three emotions. Others went up to 27. Others had 16. Some were in the middle. So we were kind of left with no definitive answer to our basic question - how many are there?

Dr. Paul Ekman, who worked in San Francisco - still does - which is where Pixar Animation Studios is, he had early in his career identified six. That felt like a nice, manageable number of guys to design and write for. It was anger, fear, sadness, disgust, joy and surprise.

So we can sit with Lee Unkrich and Andrew Stanton, and all the other folks and experience what the film is going to be like. And then we go away into a room, and we talk about what worked and what didn't. And then we take all of those findings and we do that whole process again.

We actually needed the memory - if you see the film - as a very different kind of a plot device of revealing some information to our main character. So we chose to represent it as these sort of beautiful little snow globes, which kind of, weirdly, that's the way we think of memories - at least, most of the folks that we talked to. You think of these memories as being very pure and absolute and unchanging. That's not actually real life.