The Time Patrol And The Temporal Bureau II

The Temporal Bureau exists so that Robert Heinlein can tell a single circular causality short story whereas the Time Patrol exists so that Poul Anderson can present a series of stories of different lengths and even novels about interventions in historical periods. Thus, "'- All You Zombies -'" cannot have a sequel whereas the Time Patrol was eventually expanded to a considerably greater length than its original four stories.

Both organizations close causal circles although the Patrol sometimes does this in order to prevent causality violations which are impossible in the Temporal Bureau timeline.

The Patrol operates from prehuman geological epochs at least until the time of its post-human founders a million years hence. We know that at least one Bureau operative has been in pre-Christian Crete but the organization's headquarters seem to be under the Rockies in 1992. There is no indication that the Bureau operates any later than the twentieth century.

One of the Bureau's "By-laws of Time" is: "Ancestors Are Just People," which is relevant to the Patrol agent, Carl Farness.

The Time Patrol And The Temporal Bureau

"An Unattached agent of the Time Patrol drew on unlimited funds."
-Poul Anderson, The Shield Of Time (New York, 1991), PART ONE, 1987 A. D., p. 4.

"The Temporal Bureau doesn't care how much you spend (it costs nothing)..."
-Robert Heinlein, "'- All You Zombies -'" IN Heinlein, The Unpleasant Profession Of Jonathan Hoag (London, 1980), pp. 126-137 AT p.134.

The Patrol sends time criminals to an exile planet whereas the Bureau can exile its own court-martialed members to a year in, e.g., 1974 when there is strict rationing and forced labor. In Poul Anderson's "My Object All Sublime," (see here) a future civilization exiles criminal to unpleasant past periods.

The Temporal Bureau is named once in a single short story whereas the Time Patrol fills two long volumes.

Knowledge Of The Future And The Past

HG Wells' Time Traveler knows the general course of the future because he has traveled through it and returned to his present.

In James Blish's The Quincunx Of Time,  Service agents know of the future because they receive messages from future periods, then ensure that the events described in those messages occur.

Poul Anderson's Time Patrol agents observe unrecorded past events in order to know the course of the history that they must protect from extratemporal interference.

Anderson's contending Wardens and Rangers, living in our future, try to influence their future by controlling unrecorded details of past history.

In Anderson's There Will Be Time, two groups of mutant time travelers contend. One group changes the significance of known events.

The temporal agents in Robert Heinlein's "'- All You Zombies -'" cannot prevent events but sometimes cause them.

Heinlein's Lazarus Long visits the period of his childhood but to no good purpose.

Isaac Asimov's time traveling "Eternals" change events to maximize human happiness until they themselves are prevented from existing but I argue that Asimov's narrative is incoherent. See The Logic of Time Travel: Part II, here.

There is time travel between two periods of Brian Aldiss' future history, Galaxies Like Grains Of Sand.