Demonstrates the dramatic interplay of elements that comprise the concepts of norm, bisexuality, and development. A brilliant and original reimagining of sexuality, Sleights of Reason examines how concepts lend themselves to power/knowledge formations. Many contemporary French philosophers make incidental use of the notion of a ruse. Its names are “duplicity,” “concealment,” “forgetting,” and “subterfuge,” among others. Mary Beth Mader employs Gilles Deleuze’s philosophy of the concept to describe three specifically conceptual ruses, or sleights, that make up part of the conceptual support for the concept of sex. These are the sleights associated with the concepts of norm, bisexuality, and development. Mader argues that concepts can trick us, and shows how they can effect conceptual sleights, or what she calls sleights of reason. She concludes by offering a robust synthesis of insights from Foucault and Deleuze to extend those into a proposal for a conceptual next step for imagining the structures of sexuality as eros. “In addition to creating her own philosophical concept, Mary Beth Mader pulls off something no one else has even attempted, to my knowledge—namely, to bring Gilles Deleuze’s rigorous analyses of the nature of the concepts in What Is Philosophy? to bear on the concept of sexuality. The result is an injection of conceptual rigor into debates that hitherto have been more focused on historical considerations. This is a superb book.” — Daniel W. Smith, coeditor of Gilles Image and Text “Somewhere between mere errors and dialectical illusions, Mader’s ‘sleights of reason’ are biases that derive from the ability of concepts to refer to themselves. Tendentious concepts such as ‘norm,’ ‘bisexuality,’ and ‘development’ purport to refer to actual objects, but actually refer only to their own ability to structure experience. Like Jacquemarts, they hammer home a way of thinking, repeatedly striking us as self-evident features of the world. By showing in detail how the three sleights of her subtitle came to govern modern conceptions of sexuality, Mader frees us from their conceptual bell tower.” — Andrew Cutrofello, author of The Owl at A Sequel to Hegel’s Phenomenology of Spirit