I heard the stars & girlfriend story a little differently; it was Maxwell with a girlfriend, and he told her that he was the only person who knew what starlight really was (electromagnetic waves).

Anyway, isn't one difference between discovering something that's "new" and something that's already been discovered is that, well, when something new is discovered, it might be something that can "change the world", as it were, but something already known has "already changed the world" so the benefit is less. (I think I didn't say that very well...)