Baseball might usually be a metaphor for life, but in Good Will Hunting, baseball is a metaphor for luuuuurve.
In one of the famous scenes from this movie, Sean Maguire tells Will all about the time he and his friends slept out on the sidewalk all night to get tickets to game 6 of the 1975 World Series. But when the time came to go to the game, he "just slid my ticket across the table and I said, 'Sorry guys, I gotta see about a girl.'"
The reason he ended up missing the game is because he had just met his future wife, Nancy, and he wanted to be with her more than anything else. The whole point of this story is that Maguire knew right away that he wanted to be with his wife. It was love at first sight. Aww, jeez.
But there's more to Maguire's story than love for his wife. He also tells it to show Will that it's worth putting your heart on the line even if you might get hurt in the end. Will asks him if he ever regrets meeting his wife because of the pain it now causes him, but Maguire answers,
MAGUIRE: I don't regret the last years when she got really sick. And I sure as hell don't regret missin' the damn game.
So when it comes down to it, Maguire wants Will to know that it's a whole lot better to have loved and lost than it is to never have loved at all.
And you know what? Will listens. He listens so well that he ends up borrowing Maguire's line—he lets Maguire know that he's decided to drive to California to be with his ladylove by writing, "Sorry, I had to go see about a girl."
Who knew that a Sox game could end up being a metaphor for love, intimacy, and daring to be vulnerable? (The answer is probably "99% of the Sox fans out there.")