The conditions under which the taking of a human life is socially sanctioned vary tremendously from culture to culture. 'Murder' is the unjustified taking of another human life. 'Murder' by no means has a universally agreed-upon definition.
To acknowledge this obvious reality is not to advocate Mansonism. Dr. Hippler's insight ('all societies prohibit murder') is naïve, as it rests on a word with a far too elastic definition.
Dr. Hippler may have then distilled his assertion into: 'No society allows people to wantonly kill anyone for no reason.'
I should have responded:
If your central position in this debate is that humans naturally converge on a single universal morality, and your evidence is that 'human societies usually don't sanction wanton mass killing'--then you have an extremely weak argument. If you believe humans naturally converge on similar moral views, why do we observe such immense diversity in kinship arrangements?
I've previously quoted a person on the MN Atheists Meetup site who attended the debate and found considerable fault with my performance.
I emailed him today and invited him out for coffee--as I am wont, when I find I have an intelligent critic. (I assured him I just wanted to learn more of his perspective and had no interest in a boxing match.) Alas he doesn't live in town, but he immediately mirrored my friendliness stance and gently retracted his one stinging word. He then honed his critique into:
...you could have made a better case during the debate, primarily by abandoning ethical relativism and admitting that there are ethical universals. The fact that some moral rules are culture-specific does not imply that all are, and the prohibition against random killing of one's societal associates, pointed out during the debate, is a clear example of a universal. Arguably, such principles derive from our evolved human nature, especially our tendencies to be social creatures who feel empathy towards others. They also derive from what we've learned as a species over millennia, and have embedded, meme-like, in cultural practices that are universal or nearly so: For instance, you simply can't have a society in which people are allowed to randomly kill their fellows, and the institution known as private property contributes to general societal well-being.The fact that all human societies prohibit random mass killing cannot be offered as proof that humans naturally converge on One Morality, can it?
The human tendency to feel empathy toward others is a similar example: Many societies have displayed shockingly little empathy toward people living in their midst; examples too numerous to mention immediately spring forth--including within our own recent history, in America. Humans are hypersocial primates, though cruelty, violence and aggressiveness are also widely observed. The human tendency to feel empathy toward others simply doesn't tell us anything interesting.
Rules for the division of property vary greatly from one culture to the next and from epoch to epoch. During most of our species' evolutionary history, individually-owned property was rare. Prevailing contemporary property ownership law is entirely a social construction: It is not the inevitable outgrowth of any built-in human moral rules-system--as can easily be verified by the most cursory examination of the anthropological record.
Different societies have come up with really, really distinct moral rule-books--with quite little observed moral convergence*. The relativist responds, 'So what? That's exactly what I'd expect!'
Since the debate I've been genuinely surprised by the prevalence--among atheists--of the assumption that the thinking non-believer is required to define one universal morality that can be accepted by everybody. To the dustbin!
*'quite little convergence' when we compare isolated human societies that haven't experienced significant influence upon each other.
The convergence in values we observe in the world today--the international love of hip-hop or anime, i.e.--has no bearing on Dr. Hippler's argument, since:
Dr. Hippler argues that humans naturally gravitate toward a single vision of the good. To show that that's correct, we'll want to look only at isolated societies. Societies whose values have cross-contaminated remove them from consideration, of course.