QuoteThere is no Booker 1.0 and 1.1 There is Booker and there is Comstock. The baptism is where that path splits. Booker goes on and has a child. Comstock goes and builds a city in the sky.The split point is when Booker picks between having the baptism or not. Liz takes him back before that choice and drowns him making it so that pick NEVER happened. BOOKER picked for that choice HE picked to kill comstock when he was "born" Liz even stops him and says" are you sure" And Booker goes ahead with it.
Booker had a child and sold her off. Comstock never had a child and built the city. The reasons COMSTOCK can not have a child is because of his constant expose to the Tear machine.
This is a good sum up