I present the following proposition for consideration: “Every human being has infinite value and therefore one can never justify killing a human being on the ground that killing that human results in a net overall increase in pleasure even for the human in question.”
What reasoning could possibly warrant believing this proposition to be true?
Let’s say we have two people debating the matter. “John” accepts the first principles of the Judeo-Christian belief system. “Sam” is a metaphysical materialist.
John: This is easy. One of the first principles of the Judeo-Christian belief system is that humans are created imago Dei, literally, in the “image of God.” God is, by definition, the most valuable of all things, and it follows that anything that is created in his likeness shares in that value. Therefore, each human has infinite value and unique dignity and cannot be traded for any other “good.” Therefore, John says in answer to the question in the heading, “never.”
Sam: Hmmm. Well . . . You see . . . Hmmm. I got nothin’.
Sam has nothing indeed. Will Provine is correct. If God does not exist and has not declared an ethical standard then there simply is no foundation for ethics. Everyone is cast adrift in a sea of conflicting opinions about the grounding of any ethical norm, including the ethical norm, “Thou shalt not commit murder.” In fact, one system of materialist ethics (consequentialism, especially the utilitarian version of it) holds that no absolute statement such as this is ever true. If you ask a consequentialist whether it is OK to murder someone, all he can say is “Does it increase overall happiness to murder that person?” If yes, go ahead and murder him. So the materialist who subscribes to consequentialism answers the question in the heading “depending on the circumstances, sometimes.”