A couple of things bother me. One goes something like this. I have a fondness for cows. When I say something like, "it seems like a shame to kill them and eat them," somebody usually says, "No, that's what they're for." As much as I love hamburger/steak, something seems wrong in that statement. Before the Civil War, if somebody said, "it seems like a shame to have slaves" doesn't the answer, "no, that's what they're for" seem wrong? How do we really know what anything is for?