 Let us now review the different elements of fully free and informed consent in some detail, starting with the notion of consent itself. English admits of both psychological and behavioral senses of consent. Psychologically, consent can designate “a state of mind of acquiescence” (Westen 2003, 5), and “an act of will—a subjective mental state…” (Hurd 1996, 121). But the medical requirement of informed consent seems to include at least some behavioral expression of consent (Kleinig 2010, 9–10), ranging from a patient’s signature, to her not protesting when a nurse approaches with a syringe (so-called implicit or tacit consent). That said, the need for some comprehension and voluntariness means that mental states also affect when consent legitimizes medical intervention, perhaps supporting a hybrid view of one sort (Miller and Wertheimer 2010, 84) or another (Alexander 2014).