“The mere fact that the community demands the murderer's life in return for the evil he has done cannot sustain the death penalty, for as Justice Stewart, Powell, and Stevens remind us, "the Eighth Amendment demands more than that a challenged punishment be acceptable to contemporary society.’To be sustained under the Eighth Amendment, the death penalty must compor[t] with the basic concept of human dignity at the core of the Amendment,’ the objective in imposing it must be [consistent] with our respect for the dignity of [other] men.’ Under these standards, the taking of life "because the wrongdoer deserves it" surely must fall, for such a punishment has as its very basis the total denial of the wrongdoer's dignity and worth. The death penalty, unnecessary to promote the goal of deterrence or to further any legitimate notion of retribution, is an excessive penalty forbidden by the Eighth and Fourteenth Amendments. I respectfully dissent from the Court's judgment upholding the sentences of death imposed upon the petitioners in these cases.”