“Keep Out,” an old short story by Fredric Brown

“Keep Out,” a short story by science fiction and mystery author Fredric Brown that was originally published in the March 1954 issue of Amazing Stories magazine, can be downloaded for free from ManyBooks or read for free online at Project Gutenberg. Set on the Red Planet in the year 2074, “Keep Out” is about the complexities of human nature and the difficulties they create for colonization. Here are the opening lines of the story:

Daptine is the secret of it. Adaptine, they called it first; then it got shortened to daptine. It let us adapt.

They explained it all to us when we were ten years old; I guess they thought we were too young to understand before then, although we knew a lot of it already. They told us just after we landed on Mars.

"You're home, children," the Head Teacher told us after we had gone into the glassite dome they'd built for us there. And he told us there'd be a special lecture for us that evening, an important one that we must all attend. ...

Thanks to Dave Tackett of the blog QuasarDragon for the tip.