Close just one eye and you’ll not even see your eyelid. You can test it by turning on your phone’s flashlight, closing your eyes, pointing it to one of them, and opening the other.
Tested with an additional barrier between the eyes, I can still see the light. And by looking in the direction of the closed eye I can even see the red of the eyelid.
Your brain may helpfully filter out the closed eye but you can still trick it to drop the filter.
Close just one eye and you’ll not even see your eyelid. You can test it by turning on your phone’s flashlight, closing your eyes, pointing it to one of them, and opening the other.
Tested with an additional barrier between the eyes, I can still see the light. And by looking in the direction of the closed eye I can even see the red of the eyelid.
Your brain may helpfully filter out the closed eye but you can still trick it to drop the filter.