Eye / Library of Congress If you imagine your eye as a clock, then my vision is empty from five o’clock to six.  I don't see a black space; my brain fills it in with the colors of visible areas nearby.  What is actually there is invisible to me. This damage is not to my eyes, but to my brain’s understanding of vision.

Big things are not the problem. The menace is toddlers running straight at me; they disappeared into thin air.