Theory of Devolution (University of Illinois Press), David Groff’s impressive first volume of poetry, tracks HIV from crisis to epidemic to “These days my friends keep on living.” Theory’s poems stay tuned to concrete images; still, its title is a tease. Bad things, of course, have happened in the poet’s life, thus the devolution of consciousness, sacred cows and sentimentality—but not of the desires that pushed him toward them to begin with.