How come when you close both eyes you see black but when you close one eye you just see nothing?

Question

Why don’t you see black on that one eye when you close it?

In: Biology

Answer 1

Another part of this is due to overlapping fields of view. Consider this: open just your left eye; then close it and open just your right eye; then alternate back and forth. While there’s a little difference, you’re seeing mostly the same stuff, right? Each eye, with the exception of what’s on the periphery, sees almost all of the same scene content as the other (i.e. they have largely overlapping fields of view). With one eye open, we still see something like 95% of what we see when both eyes are open. With both eyes closed, our field of view is 100% reduced; however, with only one eye closed, our field of view is only marginally reduced. Therefore it makes sense that we wouldn’t notice the “blackness” of one eye being closed as easily as we would when both eyes are closed.