With philosophy traditionally seen as the way to truth, wisdom and goodness, it is to metaphysics, logic and ethics that we have historically turned to solve personal, social, and existential dilemmas, and find peace and contentment. Rarely is it noted, however, that despite two millennia of debate, philosophers have yet to produce a coherent theory of human/worldly existence. At the same time, the global incidence of mental illness has risen to what many see as epidemic proportions. This book argues that this is no coincidence. Its analysis of key metaphysical texts suggests that the entire philosophical (and religious) canon has been founded upon and distorted by an Aristotelian misconception. Through its social/discursive inscription, this misconceived metaphysics is disrupting the development of fe/male selfhood to a degree that, under further conditions, is causing mental illness. Thus, our metaphysics is making us mad, and the more muddled it gets, the more disordered we become. The testing of this theory via eating disorder research supports a new `spirogenetic' model of subjectivity that resolves not only mental illness, but also the ancient mysteries of the Holy Grail and Philosopher's Stone.