I've always believed in populating my films with characters who we like, who we have some warmth for, who have warmth for each other, who we would like to hang out with, who we emulate in one way or another. It's not that they all get along, or that there aren't bad people or people we make fun of. But at the core, there's a kind of sweetness.

I'd always been a science fiction enthusiast.

I believe that improvisation is really just a directorial tool. It's a writing tool. It's not so much that the actors get to say whatever they want, whatever pops into their head. It's an opportunity to write the last draft of the screenplay as you're working on it.

I remember when first, Stripes, and then Animal House came out - which I was really proud of, even though it was kind of loose and quite raucous - there were imitative movies that were not quite as good.

I call it like the domino theory of reality. If you can go one step at a time and it seems to make sense, you can then take your audience into an area that is relatively outlandish.

The real trick for me as a director is to make sure that people don't start pushing because the harder you push as a perform the less funny it becomes.

I never like to do parodies. I never do. It's just not my style of comedy.