A Sound of Thunder

by

Ray Bradbury

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Themes and Colors
Cause and Effect Theme Icon
Authoritarianism, Fascism, and Nostalgia Theme Icon
Mortality Theme Icon
Environmentalism Theme Icon
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Cause and Effect Theme Icon

In “A Sound of Thunder,” Ray Bradbury imagines a world in which humanity can take touristic journeys back in time. As Eckels, a man on a prehistoric hunting trip, discovers, however, even the slightest alteration to the past can forever alter the course of history; after accidentally crushing a butterfly underfoot 65 million years ago, Eckels returns to a present drastically different from the one he’d initially left behind. Small actions can have major repercussions, and, as with much of Bradbury's work, the tale condemns the hubristic use of increasingly powerful technology in a world that human beings do not fully understand. By emphasizing the drastic effects of something as seemingly mundane as crushing a butterfly eons in the past, the story suggests the intimate connection between the past, present, and future, and ultimately argues that every action, no matter how small, has consequences.

The company offering the time travel experiences, Time Safari, Inc., at first seems to understand the dangers of altering the past, as is evidenced by the precautions and warnings given to potential travelers. The company emphasizes that it does not guarantee any particular outcome—not even its clients’ safe return. Before setting off, Eckels has to sign a release of all liability, which the company’s agent explains in terms of danger during the safari: “Those dinosaurs are hungry.” The company has also set up anti-gravity pathways to prevent safari goers from interacting with the world around them and pre-selected dinosaurs that would have naturally died within minutes of being shot by time-traveling hunters anyway.

Mr. Travis, Eckels’s guide, explains the theory behind the company’s many safety precautions to ensure minimal effects on the past from their safaris. At such a great distance into the past, he says, tiny shifts could snowball over time and have a huge impact on human civilization. Things that seem small to Mr. Eckels because they have little impact in an ordinary human lifetime, such as stepping on a mouse or a plant, could mean much more when the time scale of their consequences is millions of years.

Nonetheless, there are penalties in place for the possibility that someone might go off the path—suggesting that the company’s precautions are not as failsafe as they should be, given its alleged appreciation of the danger of altering the past. While the company can account for some causes that might lead to changes in the past, and therefore the present and future, it overestimates its ability to control events and overlooks the ever-present element of chance. For example, when the dinosaur frightens Eckels, he does not have the presence of mind to follow instructions and return to the time machine. Instead, he wanders off the path, and the safari guides do not notice until the damage is already done.

Bradbury seems to thus be presenting a sort of naïveté on the part of humankind; the company paradoxically articulates the immense danger of changing the past in any way, yet also foolishly believes in its own ability to safeguard against such changes. Mr. Travis admits, “Maybe Time can’t be changed by us […] We don’t know. We’re guessing.” The precautions taken by Time Safaris, Inc., then, are based on an incomplete understanding of what time travel technology can do. This element of uncertainty gives the scenario a hint of recklessness, as human beings are meddling with powers they do not fully understand.

Even the smallest slip-up proves enough to set a cascade of historical changes in motion. When Eckels wanders off the path, he does little more than trample a few plants and step on a butterfly. This tiny act of destruction, however, sets in motion a total political upheaval and even changes to the English language back in the year 2055. The first hint that Eckels sees is the sign in the Time Safaris, Inc. office, which now reads “TYME SEFARI INC.” He quickly discovers that the changes go much deeper than simple spelling, this time with an ironic twist. When Eckels first arrived in the office, he joked with the company’s agent about the possibility of wanting to escape the present if Deutscher rather than Keith had won the election. Upon returning, he finds that his trip to the past has caused Deutscher to win after all.

The plot of “A Sound of Thunder” hinges on the idea that the relation between cause and effect is far more complex than humans might like to think. Bradbury uses the conventions of science fiction to explore the consequences of using technology without fully understanding it. His story anticipates a future when humans will be able to meddle with history, and demonstrates how futile and and misguided such an effort would be. Bradbury urges readers to raise the question of whether some technological advances serve only to facilitate human hubris.

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Cause and Effect Quotes in A Sound of Thunder

Below you will find the important quotes in A Sound of Thunder related to the theme of Cause and Effect.
A Sound of Thunder Quotes

Out of chars and ashes, out of dust and coals, like golden salamanders, the old years, the green years, might leap; roses sweeten the air, white hair turn Irish-black, wrinkles vanish all, everything fly back to seed, flee death, rush down to their beginnings, suns rise in western skies and set in glorious easts, moons eat themselves opposite to the custom, all and everything cupping one in another like Chinese boxes, rabbits into hats, all and everything returning to the fresh death, the seed death, the green death, to the time before the beginning.

Related Characters: Mr. Eckels
Page Number: 212
Explanation and Analysis:

Not knowing it, we might kill an important animal, a small bird, a roach, a flower even, thus destroying an important link in a growing species. […] The stomp of your foot, on one mouse, could start an earthquake, the effects of which could shake our earth and destinies down through time, to their very foundations.

Related Characters: Mr. Travis (speaker), Mr. Eckels, Lesperance
Related Symbols: Butterfly
Page Number: 214-215
Explanation and Analysis:

“It can’t be killed.” Eckels pronounced this verdict quietly, as if there could be no argument. He had weighed the evidence and this was his considered opinion. The rifle in his hands seemed a cap gun. “We were fools to come. This is impossible.” […] Eckels, not looking back, walked blindly to the edge of the Path, his gun limp in his arms, stepped off the Path, and walked, not knowing it, in the jungle.

Related Characters: Mr. Eckels (speaker), Mr. Travis, Lesperance
Related Symbols: Thunder
Page Number: 218-219
Explanation and Analysis:

We can’t take a trophy back to the Future. The body has to stay right here where it would have died originally, so the insects, birds, and bacteria can get at it, as they were intended to. Everything in balance

Related Characters: Lesperance (speaker)
Related Symbols: Butterfly
Page Number: 220
Explanation and Analysis:

This ruins us! We’ll forfeit! Thousands of dollars of insurance! We guarantee no one leaves the Path. He left it. Oh, the fool! I’ll have to report to the government. They might revoke our licence to travel. Who knows what he’s done to Time, to History!

Related Characters: Mr. Travis (speaker), Mr. Eckels, Lesperance
Page Number: 221
Explanation and Analysis:

Eckels felt himself fall into a chair. He fumbled crazily at the thick slime on his boots. He held up a clod of dirt, trembling. “No, it can’t be. Not a little thing like that. No!”

Embedded in the mud, glistening green and gold and black, was a butterfly, very beautiful and very dead.

“Not a little thing like that! Not a butterfly!” cried Eckels.

Related Characters: Mr. Eckels (speaker)
Related Symbols: Butterfly
Page Number: 223
Explanation and Analysis:

“Who won the presidential election yesterday?”

The man behind the desk laughed. “You joking? You know very well. Deutscher, of course! Who else? Not that fool weakling Keith. We got an iron man now, a man with guts!”

Related Characters: Mr. Eckels (speaker), Company agent (speaker)
Page Number: 223
Explanation and Analysis:

… “can’t we take it back, can’t we make it alive again? Can’t we start over? Can’t we—”

He did not move. Eyes shut, he waited, shivering. He heard Travis breathe loud in the room; he heard Travis shift his rifle, click the safety catch, and raise the weapon.

There was a sound of thunder.

Related Characters: Mr. Eckels (speaker), Mr. Travis
Related Symbols: Thunder, Butterfly
Page Number: 223-224
Explanation and Analysis: