" Essentially, there are three types of problem. First, doubt may be raised whether anything can be bad for a man without being positively unpleasant to him: specifically, it may be doubted that there are any evils which consist merely in the deprivation or absence of possible goods, and which do not depend on someone’s minding that deprivation. Second, there are special difficulties, in the case of death, about how the supposed misfortune is to be assigned to a subject at all. There is doubt both as to who its subject is, and as to when he undergoes it. So long as a person exists, he has not yet died, and once he has died, he no longer exists; so there seems to be no time when death, if it is a misfortune, can be ascribed to its unfortunate subject. The third type of difficulty concerns the asymmetry, mentioned above, between our attitudes to posthumous and prenatal nonexistence. How can the former be bad if the latter is not? "

― Thomas Nagel , Mortal Questions