Chapter 5 examines to what extent metabolisms are renewable and even replaceable, through the feature of willpower and the science of surgery. It is concerned with absorptions between the body and willpower. It considers what kinds of treatment for obesity are possible when drugs and diet fail. The chapter explores the phenomenon of metabolic surgery, in which surgeons attempt to reconfigure the inner organs such as the stomach and intestine to “adjust” the invisible force of the metabolism. Overweight people turned to metabolic surgery to free themselves from their perceived frailties of willpower over consumption, based on the belief that their bodies could no longer be further disciplined by diet. The surgery promises to cure metabolic disease by targeting the metabolism as a biomedically manageable proxy for the will. In this context, intervention upon the metabolism shows the promise of a fix for the intransigencies of metabolic disorder.