There's something really emotional about not having any sound. That allows, I think, the audience to participate more actively and kind of imagine what are they talking about there?

Well, the film initially - we had decided to pair joy with fear because I don't know about you - for me fear was a major motivator in junior high. So we thought there's probably some good stuff there... As the film went on, we had developed all these great scenes that were really funny, but in the third act, it wasn't adding up to anything.

The way real memories work, from what we understand, is really complex. And it's an interconnection of different things and redundancy in the brain. So the idea of a memory existing as a little snow globe - the way we represent it in the film - is actually not scientifically accurate at all.

It might have been introduced slowly over the course of the years as you recall this memory over and over. So that was a very cool but complex idea that we thought about representing in the film but could not find a way to make it work.

Any great movie you watch has some element of darkness or loss or some suffering in it. That's what makes the fun parts fun.

The drive of the story is sort of hinted at the beginning, is Joy and Sadness and those two characters. Especially Joy starting to understand that there's more to life than being happy. And so that's based on real life observations and things that we've learned as adults.

There's something really emotional about not having any sound. That allows, I think, the audience to participate more actively and kind of imagine what are they talking about there?