 One such area is medical ethics, where proposed conditions for autonomous informed consent often reference the need to ensure that consent is not manipulated. In fact, one of the earliest sustained philosophical discussions of manipulation appears in Ruth Faden, Tom Beauchamp, and Nancy King’s influential book, A History and Theory of Informed Consent (1986). The view that manipulation undermines the validity of consent is widely held among medical ethicists. However, there is far less agreement about how to determine whether a given form of influence is manipulative. Nowhere is this lack of agreement more apparent than in recent discussions of “nudges”.