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Probability

Written by Louis Trimble

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About this book

"Probability" by Louis Trimble is a science fiction short story written during the early 1950s. The narrative explores the life of Mike Murphy, a bartender, and his interactions with a peculiar customer named Rabelais Pettis, who seems to lead a mundane life yet harbors a secret involving time travel and probability. The story blends humor and speculative elements, particularly focusing on the impacts of small choices on future outcomes. The plot unfolds as Mike Murphy develops a friendship with Rabelais, witnessing his transformation from a timid regular into a wealthy man who can manipulate time. After a series of raucous events, they embark on adventures through the near future, experiencing changes in wealth, status, and even potential fame for Mike. However, the tale pivots when Mike learns that their previous timeline may lead to catastrophic consequences, and Rabelais wants to guide him towards a path of political influence to avert disaster. The story culminates as Mike navigates the challenges of this new trajectory, maintaining a sense of uncertainty about the impact of their actions on future history while ultimately embracing the changes ahead.

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Reading guide

Themes, characters and key ideas in Probability, written by Chaptra AI.

  • about 3 hours
  • intermediate
  • humorous
  • speculative
  • thought-provoking

Louis Trimble's 1950s science fiction short story, "Probability," chronicles the unlikely friendship between Mike Murphy, a bartender, and Rabelais Pettis, a seemingly ordinary customer who secretly manipulates time and probability. The narrative follows Mike's astonishment as Rabelais transforms from timid to wealthy, leading them on adventures through the near future, altering their lives and status. However, their journey takes a serious turn when Mike learns their current timeline risks catastrophe, and Rabelais guides him towards a path of political influence to avert disaster. The story ultimately explores the profound impact of small choices on future outcomes, leaving Mike to navigate an uncertain but critical new destiny.

Every coin toss, Mike, is a universe born. And sometimes, you get to flip the whole damn cosmos.

Key themes

The Impact of Small Choices / The Butterfly Effect
This theme is central to the story, exploring how seemingly insignificant decisions or alterations to probability can lead to vast, unforeseen consequences across time. Rabelais's initial manipulations for personal gain demonstrate this, but the theme deepens when the cumulative effect of these changes is revealed to potentially lead to global catastrophe, underscoring the delicate balance of cause and effect.
Free Will vs. Determinism
The story grapples with the tension between predetermined fate and the capacity for individual choice to alter destiny. Rabelais's ability to manipulate probability suggests a world where outcomes can be changed, implying free will. However, the discovery of a 'catastrophic' default timeline hints at a deterministic underlying current that requires active intervention to prevent, raising questions about whether they are truly exercising free will or simply choosing among a pre-existing set of probable futures.
Responsibility and Intervention
Initially, Rabelais's powers are used for personal gain, but the narrative pivots to explore the moral and political responsibility that comes with the ability to foresee or alter future events. The realization of impending catastrophe compels Rabelais to guide Mike towards a path of political influence, highlighting the ethical imperative to act when given the means to prevent widespread suffering, even if it means sacrificing personal desires for a greater good.

Worth discussing

How does Trimble use humor to make complex ideas like time travel and probability accessible?

Chapter-by-chapter breakdowns, character arcs and the full thematic analysis come with a free account.

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