This is a philosophical short story I read in the 80s.
On an alien planet the most intellectually advanced beings are creatures with no arms and one foot to hop around on.
They are highly intelligent but have no civilization or technology, or even ability to make things. They just lie around in the sun philosophising and speculating about things, imagining how they might do them in theory only.
One day one of them has as idea and somehow manages to tame a number of monkey-like creatures, stupid but dexterous with their hands. He has them make physical examples of some of his mental inventions.
Over a very short period of time the planet is completely industrialised. Their technology advances by leaps and bounds because they already had plans for everything worked out in principle.
At the end of the story an individual sits on a hill watching a spaceship launch and wonders if they wouldn't have been happier as they were.
I remember this as having a bit of a fable vibe to it.
Edit: I'm pretty certain about the one foot and hopping around. That bit stuck in my mind.
