Poul Anderson's "Turning Point" (short story, first contact, free): Human space farers scared by aliens with primitive technology
A bunch of humanoid aliens living primitive hunter/gatherer existence on an earth-like world the humans will call Joril. A human ship, not really interested in colonization but only for a brief stop over, lands near a village.
Human space farers have well understood & practiced ways of dealing with alien aboriginals - only "there were certain disturbing symptoms", in spite of general peace & primitive local technology.
For one thing - locals seem to learn too fast. As the story progresses over a span of several days, humans discover an extremely scary fact - even a little child here has intelligence that will put a human genius to shame, & their smarts are well beyond the grasp of human mind.
They have primitive tech only because they never needed it. But now that they know - they are moving way too fast. How to protect humanity from an onslaught that is bound to happen soon?
Many options are considered & discarded - including exterminating the communities the visitors came into contact with. Ultimately a peaceful solution...
Fact sheet.First published: Worlds of If, May 1963.
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