What you guys forget is that the person getting all the recognition was simply the first to claim an idea, theory, or proof.
There were others like them, on the same path, studying the same material, who weren't as quick to the draw.
But humans would have ended up in roughly the same situation had we lost one of our great minds at a young age.
Who knows? Maybe there was a man before Newton who theorized about gravity, but was killed before his research was known?
Also remember that humankind has survived great intellectual losses in our history. One example is the library of Alexandria; most historians say that the collected works destroyed along with the library contained ideas that weren't suggested again until the early Renaissance, over 1000 years later. Think how advanced our civilization would be right now if we had a 1000 year head start on astrophysics, biology, philosophy, etc.