Versions Of Reality

Many possible futures and mutually incompatible fictions can be incorporated into a hypothetical multiverse. Poul Anderson, in particular, presents an extraordinary diversity of future history series. Most sf authors that have written any future history are known, at most, for one future history series, not for several. Surprisingly, even contemporary fiction by a single author can present different versions of reality. Obviously, although Anderson's various time travelers (Time Patrolmen, mutant time travelers, Wardens and Rangers) pass through the twentieth century, it is not the same twentieth century in all of these works, i.e., they cannot meet each other - still less when the passers through are immortals, visiting aliens etc.

Suppose an author confines his fiction not only to the time of writing or the near future but also specifically to a single genre? Even then, realities can diverge. Czarism is restored in one novel by Frederick Forsyth but not in others. John Le Carre describes at least two versions of MI6 with different personnel:

one is nicknamed "the Circus" because its headquarters is, counterfactually, in Cambridge Circus;

the other is nicknamed "the Office" and has its headquarters where everyone knows it is.

But maybe they can all meet in the Old Phoenix.