Let's say you've either cloned yourself a native population (the ethical option) or taken a bunch of volunteers and wiped all their memories of modern technology and society (the slightly more morally iffy option), then taken your fresh batch of blank slates and dropped them into a closed, simulated environment mimicking Earth (in this case an O'Neill cylinder spun up to either full Earth gravity or an appreciable fraction thereof) to see how they develop on their own.

This social/anthropological experiment is going nicely if you, a staff member, can stomach the slightly dodgy ethics of breeding an entire native population for what is essentially glorified roleplaying with the project overseers as the DMs/de facto gods of this neat little fantasy world you've encapsulated. For funsies, you've even genetically altered and segregated the population into three distinct species occupying different "levels" of the cylinder, which is built like an onion. But you, in your godhood, now have a problem you must address.

How do you prevent your new, primitive occupants from realizing they're living in an artificially-made cylinder? Do you come down from "heaven" to tell them the truth yourself, and risk contaminating the experiment? Do you attempt to cleverly hide it somehow by either altering the landscape to hide it or simply transferring them to a larger cylinder where the curvature would be less noticeable? Or do you simply not bother to disturb the subjects and allow them to draw their own conclusions, reacting with amusement as they form entire religions and creation myths to explain why the Earth is curved? Is there a better/best option?


4 Answers 4


If the subjects are native to the habitat or had their memories of Earth completely erased they will lack the context to realize their environment is somehow different from anything else. Even the idea of other places people might live could take ages to develop.

Great care would have to be taken to edit references to Earth and Earth-based assumptions and phrases from all educational and cultural material provided, and the inhabitants shouldn't be given access to the hull or external communications. I would also use the windowless variant of O'Neill's design, because the manufactured appearance of the windows and the openings they sit in would betray the artificiality of their world.


Aren't all Earth religions based in a concept that humankind and the world we live on was artificially created by a higher being and this higher being observes humankind and judges how they live? And even from today's people who are educated in sciences only a minority question that this may not be true.

So if your populations do not carry any previous knowledge of life on Earth and start afresh, then thinking their world was created by unknown being(s) just for them to live on would only be a natural step in the progress of their new and evolving culture.


Heinlein had a novel with similar characteristics

Basically, if I wiped all of your knowledge and put you in a box (Schrodinger) all you would know is box.

You could equate this much like Heinlein did, and rationalize human perception like that of pre-Columbian society. The Earth is flat because we believe so.

In this case your folk will probably believe their entire world to be a tin can with nothing beyond it. Till some explorer type wills it to challenge their perception.

In Heinlein's book the protagonist discovers a porthole and sees the stars realizing there is more beyond the ship.

  • $\begingroup$ What is the title of this novel? $\endgroup$
    – gerrit
    Commented Jul 5, 2018 at 11:24

Even if you've gone to all this length just for the sake of experiment - you don't need to worry about them figuring out they are on a false earth.

As you've said, their memories are wiped or non-existent, so they don't know earth is curved, or even existed In the first place. As their knowledge progresses they would discover the upward curve of their cylinder and so on, up untill they discover telescopes they would think that living on a cylinder is the norm.

And then you could mask space with bright skies or debris clouds

Imhabitants would never find out they are living on an artificial world, only that it's cylindrical

  • $\begingroup$ An O'Neill is just 16 km in diameter, so the curvature would be instantly apparent. $\endgroup$
    – rek
    Commented Sep 26, 2017 at 4:48
  • $\begingroup$ Also, the gravity is moving outwards of the cylinder I think, so they wouldn't be looking at space, but the insides, right? $\endgroup$
    – Robin
    Commented Sep 26, 2017 at 6:47

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