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We appreciate the ingenuity of circular causality paradoxes in time travel fiction but usually forget the details. Here, I summarise the paradoxes in a 1965 novel by Poul Anderson. I have omitted some details because they do not bear directly on the paradoxes.
We appreciate the ingenuity of circular causality paradoxes in time travel fiction but usually forget the details. Here, I summarise the paradoxes in a 1965 novel by Poul Anderson. I have omitted some details because they do not bear directly on the paradoxes.
Rival
regimes called "Wardens" and "Rangers" from two thousand years in our
future wage war through time and are the real cause behind historical
conflicts like Catholics and Protestants or Cavaliers and Roundheads.
They cannot change their past but hope, by manipulating social trends
and subtly altering the balance of forces, to influence their future
from which they are barred by their successors.
The
Warden, Storm, tries to lead an attack into the Ranger homeland by
driving a new time corridor through from the twentieth century.
However, the Ranger, Brann, already informed about the new corridor,
leads a counterattack down the corridor. Storm escapes alone and hires a
twentieth century man, Lockridge, to accompany her to 1827 BC and the
Danish village of Avildaro where they can await a ship to Iberia and
thence to the Warden base in Crete. When an Aryan war party approaches
Avildaro, Lockridge persuades Storm to stay and defend the village with
futuristic weapons. He and she become prisoners of Brann who leads the
war party with superior weapons and captures the village.
Brann
predicts that Lockridge will change sides because it was he who had
informed Brann of the new corridor and the flight to Avildaro.
Lockridge escapes and brings Wardens who capture Brann and free Storm.
Lockridge must then travel to the era of Wardens and Rangers and
pretend to defect to the Rangers in order to tell Brann about the new
corridor and Avildaro. Threatened with painful interrogation to confirm
his story, he escapes and returns to Avildaro where Storm plans to
build a Warden base in Stone Age Northern Europe by supervising the
intermarriage of Sea People, from villages like Avildaro, with the
Aryans.
Lockridge
cooperates despite the unhappiness of his friends among the Sea
People. Wardens Storm and Hu fly on gravity belts to investigate a
large fleet approaching from England. In their absence, Lockridge finds
that Brann is still alive but being painfully interrogated by the
Wardens. On their return, he confronts them and is held under guard but
he and a group of villagers escape when the English fleet attacks.
Before leaving, Lockridge frees Brann from the interrogation machine so
that he will die quickly. Lockridge leads his people to England twenty
five years earlier, builds a progressive federation that he already
knew of and leads the fleet that attacks Avildaro. Lockridge's wife
from Avildaro, who returns with him, sees their younger selves fleeing
from the village. Storm, captured, is bound and confined in the house
from which she had ruled where she is strangled by the dying Brann who
has just been freed by the younger Lockridge. Lockridge's confederation
builds Stonehenge of which, of course, Lockridge had known in the
twentieth century.
Comments
How
easy is it to "escape" when held captive? Lockridge does it three
times. The third time makes sense because his captors are under attack.
If he had not escaped from Brann in Avildaro, then Brann would not
have known to attack Avildaro. If Lockridge had not escaped from the
Rangers in their own era, then their "psychic probe" would have
extracted the truth from him. In that case, the Brann who had
counterattacked in the time corridor and who had captured Avildaro
would have known that he was to be captured and would have ordered
other Rangers to recapture Avildaro as soon as Lockridge had departed
for the Wardens' and Rangers' era.
