[quote]There's always a lighthouse. There's always a man. There's always a city.[/quote] I didn't spoiler block it because I put as much in the OP title. So Elizabeth says this, referring to both Rapture and Columbia. Now, if the two cities are variables, but the lighthouse, man, city formula is a constant, what does that say for a reality that seemingly contains none of these? Booker's reality? Is Rapture set in that? If we match the constants and variables between Columbia and Rapture, we discover that Jack is Rapture's Booker. So no, Rapture exists in another reality altogether. Which means that Booker's reality, in which he rejected baptism, Anna was born, and Lutece was a man.... has another lighthouse, man, city scenario. Another new BioShock. This probably isn't the case, especially given that Columbia, its lighthouse and Comstock are all nullified with Booker's death, but... it's a thought. Or does the nullification of Columbia, etc. produce [i]another[/i] city in that reality?