Evolving Thoughs, The evolution of morality:
“Morality is an “acquired dialect”, which is a very useful metaphor. Like a dialect, it is conventional, and varies by geography. It is not inborn (although the capacity to acquire it, like that of language, is), and it doesn’t correlate with biology (a Sicilian raised in Japan would speak Japanese, not Sicilian). This is what Sayre-McCord refers to as social conventions. And these things evolve at the social level, not (in general) at the biological. So to explain why, for example, it is regarded as moral to marry a first cousin in Louisiana, but not in London, while marrying within “seven degrees of kinship” in Orthodox society, or marrying anyone with the same family name in Korea (but a first cousin of a different name is acceptable) are considered taboo; these things are best explained in terms of the historical process at the level of social institutions, conventions, economic and cultural factors, rather than biology.
But explaining why it is that humans are disposed to learn and accommodate themselves to these cultural rules is another matter. Moreover, it may be that some moral rules are in fact biologically based, or biased, or at least agreeable. (…)”
