As a scholar of religion and a practicing contemporary Pagan, I am sympathetic with Kripal's arguments. It is part of my community's religious practice to seek out mystical experiences and use them to become more compassionate, more effective, and more deeply connected to other people and the environment. American society at large, however—influenced as it is by secular materialism—is often skeptical, even dismissive, of mysticism. Mutants and Mystics' case against pure materialism is simple: no matter how beautiful, transformative, or liberating mystical experiences may be, materialism struggles to explain them as anything other than brain malfunction. Since paranormal experiences are widespread—one might even say a "normal" part of the human condition—classifying them as illness is unsatisfying at best.

On the other hand, I find myself uncomfortable with Kripal's reluctance to pass judgment on how paranormal experiences are used. Chapter 7 of Mutants and Mystics deals with Whitley Strieber, a science fiction author who claims to have been repeatedly abducted by strange "visitors." Kripal acknowledges Strieber's claim that he was "raped" by the visitors in a procedure that left him with rectal pain and symptoms of post-traumatic stress disorder. To help the reader understand how Strieber came to find his visitor encounters meaningful, Kripal compares Strieber's experiences with tantric encounters with dark goddesses. Without significant knowledge of tantric mysticism, however (and perhaps even with it), it is unclear how an experience that produced PTSD could be desirable or good. Strieber himself ultimately seems to have found them transformative (or at least commercially viable). Nevertheless I feel a lack of healthy skepticism here, as Kripal gives the reader no real model for "testing the spirits," as it were.

If we are to take the paranormal as seriously as Kripal does, then we cannot ignore questions of ethics. Certainly world mythology is full of divine beings who have no respect for human boundaries or for issues of consent. But do we want to continue that pattern by seeking out relationships with "rapist" visitors? Is the UFO religion that has formed as a result of Strieber's books making a positive contribution to our culture? Or, in an era of crumbling institutions and conspiracy theories, is it simply feeding into American feelings of paranoia and powerlessness?

If we are the authors of our own reality, we have an obligation to exercise choice over our relationships with the divine. Kripal does ultimately warn us away from "uncritically believing" in the apparent meanings of paranormal experiences, and refers the reader to gnostic, esoteric, and tantric literature as tools for interpretation. Yet, without addressing the question of where mysticism shades into madness, I can't join Kripal in his unequivocal enthusiasm for consciousness expansion. Strieber's world is not one I want to help create.