Solved cryptogram
The lens in your eye throws an upside down picture onto the retina, and your brain flips it.
Biology Facts, sourced to National Eye Institute.
What it means
Any simple lens inverts the image it forms, and the eye is no exception. What reaches the retina is upside down and reversed left to right. The correction happens entirely in the visual system, and it is learned rather than built in. People fitted with prism goggles that flip the world adapt within days, and then have to adapt all over again when the goggles come off.
The claim comes from National Eye Institute, and the page it comes from was read on 2026-08-27 to confirm it still says this.
This is not the kind of claim that goes out of date, which is why it was set as a puzzle rather than a fact with a shelf life.
Solve it yourself
This fact is a cryptogram here: 73 letters over 18 different ones, graded medium.
- SourceNational Eye Institute
- CollectionBiology Facts
- Difficultymedium
- Length73 letters, 18 of them different
Nearby in the collection
The facts either side of this one.
- Royal Society of Chemistrymedium, 78 letters
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About as hard as this one
Scored closest to it by the model behind our guide to solving cryptograms.
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