Right before Doc is about to travel in the time machine and right before the terrorists arrive, he mentions how he'll see who wins the next 25 world series in a exciting voice. Somewhat implying he might try to bring that information back to use and get rich off of, like how Biff did.
But then in Part 2, Doc makes it clear he doesn't want to use the time machine for financial gain.
Hmm, something interesting there! Maybe he just said it as a way to be excited about the kind of knowledge he can learn, of which he may or may not put to any use.
shareMaybe he did change via helping Marty in the past. That whole experience made him take time traveling more seriously than he originally did.
sharemaybe he's just really into baseball (thats what your ,er, 'world series' is right?) and is curious of the future of the teams even if he's not going to make money on it.
shareI never took Doc's remarks about the World Series as anything other than curiosity. Or an example that he thought Marty would relate to.
shareDon't bring other movies to this movie's discussion board, thank you very much.
In any case, let's see.. Doc is either ALIVE or DEAD. I don't know if that's a BIG change, but yeah.