GEN122 There are … compelling reasons for rejecting the hedonistic doctrine that ethics revolves exclusively around considerations of pleasure or pain. As the bearer of the image of God, each human being possesses irreducible dignity, sanctity, and inviolability. Quantitative or qualitative factors do not affect that status.  According to the Tanna Ben Azzai, this is the pivotal doctrine of the entire Torah. J. Nedarim 9:4. Concern for the sanctity of life always overrides considerations of social utility. It is categorically prohibited to commit suicide or to kill an innocent person, no matter how much such acts would contribute to the general welfare. “Active euthanasia,” however noble the motive, can never be condoned, even if intended solely for the purpose of ending the suffering of a patient. Because of the absolute sanctity of every human life, it is strictly forbidden to take one life in order to save another life, however valuable. Ohalot 7:6, Terumot 8:12. One may not sacrifice even one individual in order to save a large number of people.  Maimonides, M.T. Yesodei Hatorah 5:5.  The only exception to this rule is when dealing with an aggressor. Be it in self-defense or in defense of another person, if there is no other way to save the victim, Jewish law mandates that one should kill the aggressor. Similar considerations rule out accepting the offer of terminally ill persons to sacrifice their lives for the benefit of another individual. However hopeless their condition, they are not permitted to donate their organs for transplants, if the procedures will inevitably shorten their lives – even if only by a few minutes. Depriving an individual of chayei sha’ah (a minimal duration of life) represents an act of killing, which cannot be condoned. Yoreh Deah 339:1. Obviously, were our ethical norms solely based upon social utility, we would adopt an entirely different attitude.  But since the overriding concern for the sanctity of life is based upon the biblical doctrine that [this verse], it is totally irrelevant that the donor of the organ is anyhow on the verge of death, whereas the prospective recipient might yet make vital contributions to society.  As bearers of the image of God, both possess equal value. ETHRESP 59-60