Abstract
Although our moral intuitions lead us to distinguish, with regard to euthanasia, between the omission to treat a terminal patient and the act of actively kill him, consequentialists deny that there is such a distinction. The article considers a logico-mathemtical difficulty following from the consequentialist approach to moral problems, arguing thus for the necessity to take into consideration also other philosophical resources to deal with the issue of euthanasia. Indeed, as soon as one considers a population varying both in its composition and in its size as the whole in respect to which the consequences of an action have to be assessed, the problem arises that there are many possible optima, so that the assessment is difficult or even impossible.