“The tribal differences that erupt into public controversy typically concern sex (e.g., gay marriage, gays in the military, the sex lives of public officials) and death at the margins of life (e.g., abortion, physician-assisted suicide, the use of embryonic stem cells in research). That such issues are moral issues is surely not arbitrary. Sex and death are the gas pedals and brakes of tribal growth. ... What’s less clear is why different tribes hold different views about sex, life, and death, and why some tribes are more willing than others to impose their views on outsiders (11).”
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