Steven Shapin in the Los Angeles Review of Books:
Eating people is wrong. But why? People of different sorts, at different times, expressing their views in different idioms, have had different answers to that question. Right now, our culture isn’t obsessed with cannibalism, though we are still unwholesomely fascinated enough to buy books and go to movies about anthropophagy among the Uruguayan rugby team that ran out of food after their plane crashed in the Andes; or about “the Milwaukee cannibal,” Jeffrey Dahmer; or Armin Meiwes’s successful, internet-mediated search for a voluntary victim (and meal) in Germany in 2001; or, most famously, about the (still controversial) dietary practices of the Donner party stranded in the Sierra Nevada mountains in 1846.
Our modern idioms for disapproving of cannibalism are limited. There is a physical disgust at the very idea of eating human flesh, though it’s not clear that this is necessarily different from the revulsion felt by some people confronted with haggis, calf brains, monkfish liver, or sheep eyes, the rejection of which rarely requires, or receives, much of an explanation. It is widely thought that cannibalism is in itself a crime, but in most jurisdictions it isn’t. (It is criminal to abuse a corpse, so eating dead human flesh tends to be swept up under statutes mainly intended to prevent trading in human body parts or mutilating cadavers.)
Modern condemnations of cannibalism largely set aside questions of moral law or natural law, with their suppositions about the nature of human beings, and thus what is unnatural.