Why did Ray Bradbury write "A Sound of Thunder"?  

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mwestwood eNotes educator| Certified Educator

While very hopeful for the future of man, Ray Bradbury, nevertheless, foresaw the dangers inherent in the use of technology by humans blinded to their own interests.  For, Bradbury felt that this preoccupation and enthrallment with technology poses a threat to human beings, who often place themselves in positions in which their destruction is possible. Consequently, Bradbury's Farenheit 451, and short stories, such as "There Will Come Soft Rains" and "A Sound of Thunder" come as warnings against the exploitation of technology for man's self-serving ends.

Much like the story "There Will Come Soft Rains," Bradbury's "A Sound of Thunder" has as its theme the dangers of overusing and abusing technology. In both stories, advanced technology is used for the pleasurable and self-serving designs of people, people who are irresponsible.  With his wealth, Eckels of "A Sound of Thunder" perceives technology as a means to his enjoyment and excitement.  However, when he is confronted by the dinosaur that he wishes to kill after going back in time, Eckels loses his nerve.  Worse than this, he steps off the virtual  path and onto the earth of eons ago, inadvertently crushing a butterfly. Then, after the time-travel ship returns to the present time,

The room was there as they had left it. But not the same as they had left it. The same man sat behind the same desk. But the same man did not quite sit behind the same desk. Travis looked around swiftly. "Everything okay here?" he snapped.

The death of the butterfly has, indeed, changed the course of history, and Eckels act has set in motion a rippling effect with Life.

Eckels stood smelling of the air, and there was a thing to the air, a chemical taint so subtle, so slight, that only a faint cry of his subliminal senses warned him it was there....What sort of world it was now, there was no telling....

The mere killing of one butterfly has had momentous effects.  When technology interrupts the ways of nature, there are lasting results, Bradbury seems to say.