 This ambiguity is resolved in "Conclusions" when Josie's clone reveals that the Janitor is an observer of observers.The observers are a people to guard and maintain the time stream against those who would manipulate time travel and alter history for their own ends.While the Josie Clone was also trained as an observer when the Janitor took her to the future it is made clear in "Conclusions" that he is from a much more distant point in the future and acts as the observer of the other observers.