Well, what if we did this in the mind as opposed to the brain? So instead of blood vessels and dendrites, what if it was consciousness and dream production? And that would allow us to have characters that represent emotions. And that felt like, man, that's exactly what animation does best - strong, opinionated, caricatured personalities. And that just got me excited.

And usually I'm not watching the screen. I'm kind of sitting and looking off to the side, spying on people to see what they react to' cause it's - as Joe Ranft used to say, you know, animation is like telling a joke and waiting for three years to see if anyone laughs

Yeah, we were looking for a way to represent adulthood and the passing into adulthood. And I think, for me personally and a lot of the folks that I work with, childhood is kind of a sacred, special kind of point in time that has a real joy and purity to it. And we sort of long on a daily basis to reach back and kind of grab onto that in some way.

One of the other experts we consulted with, this guy named Dacher Keltner, he was big on sadness as community bonding - I think is the word he used.

Well, we try to - we definitely try to have a balance. And I think things have gotten a lot better at Pixar. When we did "Toy Story," that was an all hands on deck situation that really was time intensive.

People are funny -- they are able to project personality onto anything. I remember as a kid I spent a $ 5 bill once and felt so bad because the other $ 5 bill was now going to be lonely without all the other bills I had in my wallet, you just invest these dead things with life and that is our tendency as people. So animation takes advantage of that, grabs on to it, and runs with 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?