The issue of brain death shows how advances in medicine may not provide ultimate answers to profound human questions. In Evangelium Vitae, Pope John Paul II calls to mind the moral confusion which arises wherever technological progress is not directed, formed, and nourished by knowledge and love of God:

[W]hen he denies or neglects his fundamental relationship to God, man thinks he is his own rule and measure, with the right to demand that society should guarantee him the ways and means of deciding what to do with his life in full and complete autonomy. It is especially people in the developed countries who act in this way: they feel encouraged to do so also by the constant progress of medicine and its ever more advanced techniques. By using highly sophisticated systems and equipment, science and medical practice today are able not only to attend to cases formerly considered untreatable and to reduce or eliminate pain, but also to sustain and prolong life even in situations of extreme frailty, to resuscitate artificially patients whose basic biological functions have undergone sudden collapse, and to use special procedures to make organs available for transplanting. (64.2)