: Lots of people in the halo verse wanted it. Librarian wants us to have it.
: Didact wants us not to have it. As a player I'm asking, "Why should I
: care about it?" I like to "do the right thing". But I don't
: see why only one race can have it. If you think that caring about others
: is good then isn't it best if everyone shares in that belief and everyone
: tries to help? Let everyone who wants it share the mantle. Why be precious
: about it?

: I'm not saying that YOU are being precious. I'm just asking a general
: question. I've never understood why adults would only want the mantle for
: their own race. It smacks of pride and sounds like the white man's burden.
: It also sounds like they don't trust the other races. Wanting to possess
: the mantle is arrogance and attaining the mantle for humanity is not a
: gameplay motivator for me.

"Ownership of the Mantle lies with those whose evolution is most complete."

I think that's the quote. That's off the top of my head.

While the idea could certainly be explained much better, I think it pretty much amounts to:

Would you rather have an uneducated, still-growing child making moral and ethical decisions, or an adult who has had time to experience more and find balance within their own life?

Obviously, it's an idealistic view. The Forerunners, it is very clear, were not worthy of the Mantle, and their society was slowly torn apart from within due to their various conflicting ideas about what the Mantle actually means.

It's incredibly rare for a race to advance to the same societal stage as the Forerunners (and beyond, to the level of the Precursors, before their corruption). Because it is so unlikely, it would be rare for more than one to achieve this state at the same time. As such, the race which has reached this point and has had the most time to meditate on the sanctity of life and apply this understanding to their society is the one to protect the galaxy's inhabitants. This serves as a reminder and a deterrent to this society possibly breaking down and betraying these very teachings (as the Forerunners' did). When one race is no longer worthy, they will either pass the Mantle on to the next worthy successors, or will likely be wiped out by this imbalance in their society, combined with their level of power.

I think where fans are getting mixed up is that they're assuming the Forerunners were executing the Mantle as it was supposed to be, rather than seeing it as their flawed understanding of the Mantle.