I have a question for our materialist friends. Let’s imagine a group of chimpanzees. Say one of the male chimps approaches one of the female chimps and makes chimp signals that he wants to have sexual relations with her, but for whatever reason she’s not interested and refuses. Is it morally wrong for the male chimp to force the female chimp to have sex with him against her will?Recall that Darwinians claim that ethics (or morality) are simply "illusions fobbed off on us by our genes to get us to cooperate" (Michael Ruse and E.O. Wilson). If that's so then the Darwinian pretty much has to say that what the hairless ape does is not significantly different from what the hairy ape does. The materialist (or naturalist) has no grounds, in other words, for saying that rape is wrong, but will insist nevertheless that it is. Just don't ask him to explain why.
If you answer “no it is not morally wrong,” imagine further a group of humans. On the materialist view, a human is just a jumped up hairless ape. Is it morally wrong for a human male to force a human female to have sex with him against her will? If you answer “yes, it is morally wrong,” I certainly agree with you. But please explain why on the materialist view it is not wrong for a hairy ape to force a female to have sex with him, but it is wrong for a hairless ape to force a female to have sex with him.
Actually, not all of them will insist that it's wrong. Some of the more thoughtful naturalistic materialists will admit they can't really say that. They acknowledge that, on materialism, there simply is no right or wrong, good or bad.
Thus, biologist Richard Dawkins: "What's to prevent us from saying that Hitler was right? I mean, that is a genuinely difficult question."
Or philosopher Joel Marks: "There is no morality....Even though words like 'sinful' and 'evil' come naturally to the tongue as, say, a description of child-molesting, they do not describe any actual properties of anything. There are no literal sins in the world because there is no literal God."
And philosopher Richard Rorty: "For the secular man there's no answer to the question, 'Why not be cruel?'"
Even serial murderer Jeffrey Dahmer saw clearly the implications of naturalistic materialism: "If a person doesn't think there's a God to be accountable to, then what's the point of trying to modify your behavior to keep it within acceptable ranges?"
We could go on, but the point is clear. Materialism, or naturalism (atheism), leads to moral nihilism. Imagine living in the materialist's dream society, a society that has extinguished belief in God. It's a society in which the hairless ape's rape is no different than the hairy ape's rape. It's a Hobbesian society of war of every man against every man in which life is nasty, brutish and short.
We can deny God's existence and authority or we can cling to the notion that rape really is objectively wrong, but we can't do both. Ideas have consequences.