A reader writes:

I find this series of posts fascinating, partly because new science about the natural world is inherently interesting, but mostly because it raises profound questions about the relationship between the natural and the moral.  Too often the evolutionary psychology crowd leaps straight from one to the other (which even the title of the posts does), whereas I see morality, in many of its dimensions, as the attempt to constrain what is natural.  This is because I am a Christian and believe in the doctrine of original sin - not the shallow and narrowly sexual form that talk of original sin often takes, but the deeper sense that our human essence, including our biological essence or DNA - is corrupt as well as beautiful.  We simply cannot look to animal behavior, or our own genes, as guides for living and expect to remain civilized.

Surely murder is natural, and we may well find genes for violence; chimps are well-known killers.  This influences my thinking on the morality of murder not one bit.  Likewise, I have no reason to doubt the latest findings on the infidelity of monogamous birds or the health benefits of a mid-life testosterone boost, but I can't help thinking that the research is fueled in part by horny middle-aged nerds looking to justify their wandering ways.  I am not a sexual puritan by any means. I simply find these genetic and evolutionary arguments utterly irrelevant when the conversation turns to morality.

Somehow, we have to find a balance between what is natural and what is moral. This isn't easy. I find the attempt to separate them completely unpersuasive - but I agree with my reader that there's a lot of cherry-picking going on in the conflation of the two as well.

For me, original sin becomes much more comprehensible through a Darwinian prism. Our DNA is full of things - violence, selfishness, abuse, hatred - that are perfectly "natural" from an evolutionary point of view, but desperately in need of restraint when combined with humankind's formidable pre-frontal cortex and its increasing capacity to inflict damage of planet-wounding proportions. We are neither beasts nor angels, but as time goes on and our capacity for damage increases, we'd better try reaching for the angels more persistently.

Our task is not to deny our nature, but to channel it, with God's help, and through practice, to better ends.

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