Since the beginning of time, people have wondered about and speculated over both the existence and nonexistence of life after death. However, concrete signs of death itself were expected to go without saying, that is if recurrent anxiety attacks caused by the risk of being buried alive are cast aside. Today, medical progress has put a new skew on this question. Advances in reanimation and organ transplants have lead to the adoption of a brain-focused definition of death. The latter is quite clear operationally and empirically speaking, though it remains mysterious in its conceptual foundations. Is brain death indeed synonymous with death of the conscience or does it actually denote the ceasing of the complete and coherent functioning of the human organism? Unlike the widely found view, it is in fact this second interpretation which justifies the concept of brain death. Nevertheless, the concept remains a controversial one should it be suspected as being too lax in regard to the demands of transplant medicine, its theoretical validity be contested, or even a neocortical definition of death be preferred, which would be the material correlate of the death of the mind.