This book is not about the medical, psychological, psychiatric, sociological, statistical, or even theological aspects of suicide. It does not investigate the pathology of why some people kill themselves and it certainly does not attempt either to prevent or to encourage suicide. It is a book on the philosophy of suicide. It examines (1) the ontology of suicide, i.e., what suicide is from the perspective of being, and (2) the ethics of suicide, i.e., whether suicide ought to be morally permitted and what its effects in the world are when it is. In other words, it is about the "axiology," i.e., the "theory of the value" of suicide. Toward this end, it occasionally considers historical, biographical, and literary cases.