Migraine blindness starts with the funny feeling that I've missed a clue, that someone's pulling a prank on me. I know what to look for, and I spread my right hand in front of my face, palm up, and stare at the tip of my baby finger. My thumb disappears. If I let my eyes stray toward where my thumb should be it will reappear, but fix my eyes on my pinky again, and it vanishes. As soon as I check, I am aware that I have known of the problem for some time, but that it has only now reached my conscious attention. Things have been missing (ears, page numbers, the arm of a sofa) but I have been filling in for them. Now that I am paying attention, reading becomes impossible; the ending of a long word disapp . Everyone is one-eyed, smiles are weirdly abbreviated. Try driving; indeed, try walking in this condition. Objects appear out of gopher holes, or lumber toward me on half their ordinary complement of wheels, or cross my path and vanish. Soon, this simple absence becomes visible. A shimmering arc stands before me. It is energetic and purposeful. Quickly, it lengthens and becomes more elaborate. It moves when my eyes move, and I can see it with my eyes shut. Within the scimitar are short flashing vanes of light that ripple across the arc in quick succession, at varying angles to one another. The arc becomes a blazing shield that blots out the whole right side of the world. Its surface is hectic with churning blades of light. Then the blades fade back, the churning calms to a slight eddy, the whole apparatus recedes. There is something both horrible and magnificent about the chimera that visits me and borrows my eyes for the duration of this ceremony, twenty minutes, then rolls on its way. When I have my eyes back I am not sure I know them. The healed real world looks whole, but its colors are a little tawdry, it turns up at the edges. I keep checking to make sure all the pieces are there, but if something were missing, could I tell?