"What happens next, you won't believe," Chiasson writes in "From the Life of Gorky," and it is fair warning. This collection suggests that a person is like a world, full of mysteries and wonders-and equally in need of an encyclopedia, a compendium of everything known. The long title sequence offers entries such as "The Sun" ("There is one mind in all of us, one soul, / who parches the soil in some nations / but in others hides perpetually behind a veil"), "The Elephant" ("How to explain my heroic courtesy?"), "The Pigeon" ("Once startled, you shall feel hours of weird sadness / afterwards"), and "Randall Jarrell" ("If language hurts you, make the damage real"). The mysteriously emotional individual poems coalesce as a group to suggest that our natural world is populated not just by fascinating creatures-who, in any case, are metaphors for the human as Chiasson considers them- but also by literature, by the ghosts of past poetries, by our personal ghosts. Toward the end of the sequence, one poem asks simply, "Which Species on Earth Is Saddest?" a question this book seems poised to answer. But Chiasson is not finally defeated by the sorrows and disappointments that maturity brings. Combining a classic, often heartbreaking musical line with a playful, fresh attack on the standard materials of poetry, he makes even our sadness beguiling and beautiful.