What do biologists study when they study life today? Drawing on tools from rhetoric and poststructuralist theory, the author argues that the ascent of molecular biology, with its emphasis on molecules such as DNA rather than organisms, was enabled by crucial rhetorical softwares. Metaphors such as the genetic code made possible a transformation of the very concept of life, a transformation that often casts organisms as information systems. With careful readings of key texts from the history of molecular biology such as those of Erwin Schrsdinger, George Gamow, Jacques Monod, and Fran ois Jacob the author maps out the complex relations between the practices of rhetoric and the technoscientific triumphs they accompanied, triumphs that bolstered a postvital biology that increasingly elides and questions the boundary between organisms and machines.