The first Toy Story was groundbreaking for countless reasons, but the adventures of Woody, Buzz and co would never had connected so hard had they not had the character, story and dialogue to back up the then-groundbreaking visuals.
Whedon acted as one of the writers on the original movie, lending a warmth and humour that is, at times, quintessentially, undeniably Whedon-y.
Can anyone hear this classic Buzz/Woody exchange and argue that anyone but him was behind it?
Woody: "You are a TOY!"
Buzz: "You are a sad, strange little man, and you have my pity."