@Nibbin Think of it this way. In the morning you leave your house, walk for 5 min and come to a crossroads, where you can go left or right. You chose left, but because you had a choice, another universe is created where you took a right.
But, earlier, when you woke up, you had the choice of either staying in bed or getting up. You chose to get up, therby you end up at the crossroads, but this choice creates another universe in which you never got up.
Now, if 2 seconds before you get to the crossroads, someone comes and blows your brains out (yeah bad example, sorry, saw Django lastnight, it's still in my head). then the 2 universes (the left and right) are cancelled. But there is still 1 universe in which you are sleeping nicely in your bed.
So, I guess the moral is, sleeping in won't get you killed? :)
By drowning Booker, Columbia ceases to exist and Anna is just normal kid.
@Nibbin Booker ceased to exist in the universes where he arrives at the baptism. But, for example, if in one universe he never goes to the baptism in the first place, he would continue to exist
@ck10304 I doubt they're twins. In the voxophones, Rosalinda never mentions a brother, and they are simply too similar to be just twins. Robert is most likely from a parallel universe and was brought to Columbia by Rosalinda (''I should know, I've lived it'')
@TheSerpher She was probably born before and after. In some universes she could have been born before the baptism (there is one Elizabeth in the end that doesn't vanish) as well as after (the one's that vanish), or isn't born at all (Comstock's case).
In a multiverse scenario, if it can happen, it will happen.
@bledsoe45sbc @Andrei_V i think the body was just put there by the Lutece's in order to push Booker forward. They've already tried this about a million times (''Chin up, there's always next time'') so they are trying to scare him forward. The philosophy is that they don't need hi to know anything (personally i believe that explaining him the situation would have improved things), they just need him to push forward.
The lighthouse is the doorway in the universe, it's how Elizabeth can move between space (from the Rapture universe to the Columbia one) and time (from after Wounded Knee to the present, etc.)
Ok, so the ending is a play on the multiverese theory from quantum phisics, where every possible combination of an event, actually happens. For example we could have a parallel universe in which the roman empire never falls, Alexander the great never defeats Darius, etc. But it introduces something new: constants. There will allways be a lighthouse, a city, a man with an idea, a girl, some guy to bring it all down, a scientist, etc...
So, at the point of the baptism, whatever Dewitt chooses, in at least several universes he becomes Comstock and builds Columbia, in others, he joins the Pinkerton's and ,at least in one, he never goes to the baptism in the first place (the Anna that doesn't disappear). Now, by killing Dewitt, you're destroying Columbia, but you're forgetting the constants. Another one will have to take Comstock's place and build a dystopia (''There is always a lighthouse, there's always a man, there's always a city...''). You're not just taking the card out of the deck, you're also reshuffling the deck. So, basically, you're killing yourself on the chance that the guy replacing Comstock and builds the utopia, fares better than the prophet.
But the chance of that happening seems very slim. So far, the track record for utopias that stay utopias is very crappy: Columbia was a heaven of racism and slavery, that comes crashing down or tries to enslave the world, Rapture turned its people into crazy murdering junkies. Who's to say that some other nut doesn't come along and starts the 2nd holocaust? You could say that in every universe where Comstock exists, millions die. Millions will die anyway: if it's not the inquisition it's the plague, if it's not the plague it's the crusades, if not the crusades then the world wars, etc.. Just because you stop one of these doesn't mean that the next one doesn't appear or that another one doesn't take it's place. So the suicide seems kinda pointless. Either way a new city is build and you're grasping straws that maybe it will be better. If it's not Rapture it's Columbia, if it's not Columbia it's ............ (insert name of city from sequal ).
So, why drown Booker? So that in at least one universe (maybe the one where Booker doesn't go to the baptism), Anna is never sold, she never becomes Elizabeth, and the two live happily ever after.
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