Page 48 - Tales Apocalyptic and Dystopian

Into the Tempifuge

we have exchanged sterilized sand for soil from as far back as 1000
BC. The organic content is undamaged.”
“You mean—”
“Yes, Dr. Underwood. We can send you back to 1989, one year
before Mahesh Shivalingam sealed the Package. Given your
knowledge of events, you should be able to gain his confidence and
sabotage the incendiary device before it is installed. As soon as you
are transported, we will open the Package. If you have not succeeded,
then its contents will be lost. No better means is available to us to
affect the outcome.”
“Now, wait a minute.” Underwood shook his head. “I’ve always
thought that a basic paradox precluded the possibility of time travel:
you can’t alter the past. Now you tell me that you have achieved
temporal displacement. The paradox, therefore, must be invalid. So
all you have to do is send someone back there who can burglarize
Shivalingam’s laboratory and put the plans somewhere you will know
to look for them now.”
John Smith and Colonel Cruz deferred to Delirian.
“The paradox has not disappeared; it is, however, more subtle than
conceived by the man in the street. Indeed, the past cannot be
changed. But that is limited to what is known about the past, or, to
phrase it differently, anything can be changed in the past if it has no
known effect on the present. You cannot go back and prevent the
assassination of Abraham Lincoln; you might, however, stand in a
shadowy recess of Ford Theatre and witness the event. Why? No
record exists to contradict it. Furthermore, no evidence for time
travel is found in the historical record: therefore no one going back in
time has yet to leave an impression as an intruder. Anyone intending
to go back and change history will inevitably be thwarted; all that one
can do there is to live more or less anonymously, using one’s
apparently prodigious knowledge judiciously enough to avoid making
an impact on current affairs sufficiently great to merit recording. A
time traveler seriously intending to affect the outcome of significant
events may not merely be blocked by a minor obstacle; he may be
stopped by being crushed. You will have to grasp that principle very
firmly to avoid trouble in 1989, professor.”
Underwood scowled in perplexity.

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