This paper aims to analyze the problems arising from discoveries of genomics and the application of human enhancement and to present the posthuman bioethics in Richard Powers' Generosity. To explain the biopolitical system formed in the context of techno-science capitalism, this novel explores the connections between the concept of happiness and biomedical subjects and examines how the technological influences in biomedical knowledge production enters into the concept of individual self. This novel revolves around her teacher Russell Stone, the geneticist Thomas Kurton, and Thassa who always seems happy enough to be believed that her hyperthymia condition has a genetic basis. This novel shows that the heterodiegetic narrator dissolves the transhumanist discourse, in which Kurton intends to acquire the happiness gene from Thassa. In the final scene, Russell, who takes on the role of narrator/protagonist offers an alternative ending to revive Thassa through vitalistic writing. In this process, readers might distrust Kurton’s argument, because the biotechnology to create a happier population is revealed to be combined with transhumanism. In this self-reflective narrative, Powers warns a transhumanist view that sees happiness as an engineering product. In conclusion, Generosity evokes readers’ empathy that the realization and achievement of happiness is not in the mechanism of gene coding, but in the improvement of mental state. Powers presents an alternative view of happiness as a state of mind that can be obtained from exercising the resilience and appreciating the dailiness in the real world. This novel will have significance because it suggests readers to have a vitalist posthuman bioethics in terms of emphasizing a community consciousness that protects the life dignity of others, a perspective that recognizes the diversity of moral species, and a posthuman subjectivity with the interrelationship of non-human, technology, and nature.