Style is the material body of lyric poetry, Helen Vendler suggests. To cast off an earlier style is to perform an act of violence on the self. Why might a poet do this, adopting a sharply different form? In this exploration of three kinds of break in poetic style, Vendler clarifies the essential connection between style and substance in poetry. Opening fresh perspectives on the work of three very different poets, her masterful study of changes in style yields a new view of the interplay of moral, emotional, and intellectual forces in a poet's work.