Eight Keys to Eden

If you've ever had a discussion with someone on whether there is really an objective reality, or whether reality is literally what we make it, you'll find this story written in a similar vein.

Humanity is colonizing the galaxy, and has stumbled on a near perfect analog to Earth which comes to be called Eden. It's not an accident, and this name and point will be pounded into you by the end of the story.

A colony unexpectedly becomes trapped on Eden, as do their rescuers, and one 'free thinker' must plumb the depths of the above-mentioned notions of reality to find both figurative and literal liberation.

As seems typical of Clifton's work, this veers into the preachy from time to time, as if it were not enough to make a point once and carry it out in action.

Leaps and bounds better than his Hugo award winning work, so worth the read.