"We found out early that if you did something with a character, either animal or human or whatnot, that couldn't possibly be rigged up in live action, why then, you've got a guaranteed laugh. If a human can do it, a lot of times it isn't funny in animation. Or even if it is funny, a human could do it funnier....But if you can take a fellow and have him get hit on the head and then he cracks up like a piece of china, then you know you've got a laugh!"
—Tex Avery, in an interview with Joe Adamson.
Maybe I'm just a duck, but I'm human.
— Donald Duck, Early to Bed
I once said about Bloom County's Opus that when you draw a penguin sitting on the toilet reading the newspaper, it's funny, but if you put an adult man there, it's disgusting. With more fanciful characters, you're freed from the expectations and baggage of realism, and you have more latitude.
—Bill Watterson, in Exploring Calvin and Hobbes