First off, Sam, I liked the book.
My only problem is the seemingly lack of deference given to an evolutionary explanation for our moral values. The objection that if our morals evolved, it would be considered the height of morality to make daily deposits into the local sperm bank, strikes me as a simplistic straw man view of evolution. It sounds like something a creationist would say about evolution.
We didn’t evolve with Sperm banks. We evolved out of small hunter-gatherer bands. We evolved to have long term pair bonding to maximize our child rearing capabilities. Female bodies cannot bear self sufficient young. The birth canal cannot handle our large brains. That means we are all born very premature - even at 9 months, by other mammal standards. As such we require extensive protection and taking care of for several years while we mature enough to be on our own. Simply producing a lot of pregnant women isn’t going to improve one’s fitness in a hunter-gatherer society - you have to stick around. So we’ve evolved feelings of love and reciprocity to maximize the chances for long term reproductive success.
It seems to me that a proper understanding of the relationship between our moral sense (which appears to be universal and not really cultural) and evolution can help us solve the problem of what is in our best interests and what morals we should hold on to. What we are trying to do, consciously or unconciously, is maximize our reproductive success in the long term. We want to see our genes first and foremost succeed, and then those who are closely related to us, and those of our tribe, nation, and all of humanity, in that order, succeed. Ultimately we want life on earth to succeed and that requires an environmental ethic.
Reproduction isn’t just about sex, although that’s the first important step. Long term reproduction requires us to raise our children right, to provide for our economic well being, to build a stable and just society, and to preserve our ecology. That’s a moral statement that I think would get us to where we want to be a bit faster than Sam’s method.
But I’m interested in hearing other opinions.