Book excerpt: James Elkins's How to Use Your Eyes invites us to look at--and maybe to see for the first time--the world around us, with breathtaking results. Here are the common artifacts of life, often misunderstood and largely ignored, brought into striking focus. With the discerning eye of a painter and the zeal of a detective, Elkins explores complicated things like mandalas, the periodic table, or a hieroglyph, remaking the world into a treasure box of observations--eccentric, ordinary, marvelous.