Those of us in the sighted world may have walked past a blind person and asked, ''How, exactly, do they do it?'' Ryan Knighton, a creative-writing teacher whose talent shines on every page of Cockeyed, a feisty, bittersweet memoir, both answers that question and shrugs it off as he describes his 15-year descent into darkness, the result of a rare degenerative eye disease. In the beginning, he simply ignored his troubles (''At night I drove Braille. Didn't everybody?''). But when everyday living proved too difficult, he found redemption and a fascinating new way of ''seeing'' the world through the love of his patient girlfriend, Tracy, and a nifty walking cane. Along the way, Knighton explores the fascinating linguistics of blindness, but it's his penchant for disdaining pity and shame that makes this such a compelling, sturdy read.