This is the first book in a new series that will publish the very best work in the philosophy of biology. The series will be non- sectarian in character, will extend across the broadest range of topics, and will be genuinely interdisciplinary. The Immune Self is a critical study of immunology from its origins at the end of the 19th century to its contemporary formulation. The book offers the first extended philosophical critique of immunology, in which the function of the term 'self' that underlies the structure of current immune theory is analysed. However, this analysis is carefully integrated into a broad survey of the major scientific developments in immunology, a discussion of their historical context, and a review of the conceptual arguments that have molded this sophisticated modern science.