I listen to a lot of original movie scores. After a while, you learn to recognize certain traits that are typical of certain composers. I don’t know anything about how they (or orchestras for that matter) work, but I can still tell when there are some instruments and sounds that they favor. And in James Horner’s case, I recognize more than that. He’s a brilliant talent, but he sure likes to revisit his older scores to find themes he can alter a little bit and put to use in new works.
Hans Zimmer is better at stealing from himself and making it sound fresh. Just listen to the tracks above. “Time” is from Inception (2010), “Chevaliers du Sangreal” from The Da Vinci Code (2006). They’re basically the same tune, built to achieve the same kind of grandiose effect. And yet I have failed to recognize this no matter how many times I’ve listened to them. It just struck me the other day. Either I’m just stupid… or Zimmer is very clever.