But what makes us obliged not to mistreat humans? After all, if naturalism is true, "a human being is a biological animal," as naturalist Julian Baggini admits. But unless humans have unique moral worth not had by beasts, it seems objective moral truth wouldn't exist. It wouldn't, for instance, be immoral to rape or kill, for animals do so to each other regularly with no moral significance.When somebody says "it seems," that may be an indication that there isn't a solid argument. Here, for instance, Wanchick says that unless humans have unique moral worth distinct from all animals, there is no objective moral truth. The conclusion clearly doesn't follow without additional premises. The more obvious conclusion from the premise that humans are not the unique holders of moral worth is that animals also have moral worth, that mistreating and abusing them is wrong, and perhaps that it is immoral to kill animals for food--this is the conclusion drawn by many vegetarians and vegans. Moral worth is a distinct concept from moral responsibility, so the fact that animals don't respect each others' moral worth doesn't make them morally blameworthy. One can have moral worth and rights that deserve to be respected without having the capacity for moral reasoning or responsibility.
Paul Draper pinpoints the problem such properties would cause for naturalism: "every human being has a special sort of inherent value that no animal has, and every human has an equal amount of this value. Such equality is possible despite the great differences among humans, because the value in question does not supervene on any natural properties. It is a nonnatural property that all (and only) humans possess." The great naturalist philosopher J.L. Mackie, and myriad others, agree.Mackie's "queerness" argument certainly does carry some weight as an argument against the objectivity of moral properties. This argument about equality, however, I find less convincing. I would argue that the inherent value that is "equal" is that we recognize a set of individual rights for those who meet certain minimal criteria of personhood (or sentience, consciousness, capacity for pain, or whatever are the minimal features which give rise to such rights), and it is those rights which are equal, and are so for social and economic reasons. In fact, the actual value any one person has (for themselves and others) does vary from person to person based on natural properties.
Unfortunately, to defend naturalism, Draper and Mackie (like Carrier) have to absurdly deny that humans have such unique inherent worth. Carrier even says some animals are more morally valuable than certain humans in virtue of their superior intellect, rationality, etc. But such positions are obviously false. Humans have moral worth not found in animals, regardless of their comparative capabilities, and the failure to recognize this is simply a lack of moral insight.There is no argument here except bare assertion: "such positions are obviously false." Those who advocate animal rights would question Wanchick's capacity for moral insight, and since Wanchick supplies no evidence or reasons to support his position on this issue, there is no reason to prefer his position to theirs.
But since these moral properties obviously do exist in human beings and aren't natural, they must have a supernatural source. And since moral properties exist only in persons, the source of moral properties must be a supernatural person.Again, Wanchick has proceeded by bare assertion--"these moral properties obviously do exist in human beings and aren't natural"--that's two assertions, neither of which he has offered any support for. He then asserts that "moral properties exist only in persons," again without argument. I have some ideas about how such an argument could be constructed, though most of them involve non-objective meta-ethics, which would not support Wanchick's view. I don't think that Wanchick actually believes that "moral properties exist only in persons"--surely he would agree that there are particular actions that are objectively wrong, such as an axe murder. But an axe murder is not within a person, it is an action in the natural world, and for it to be objectively wrong is for that action to have moral properties. If Wanchick agrees with this, it undermines this entire argument. If he disagrees with it, then he owes an explanation for how his view is not a form of subjectivism.
The moral order, then, is evidence of a supernatural person who grounds moral truth. Additionally, at least some moral truths are necessary, and thus their foundation must be a necessary being grounding moral facts in all possible worlds.Wanchick finishes up with more bare assertion, throwing in his "additionally" remarks without any justification or argument.
I'm not sure if this is the worst of Wanchick's six arguments, but it's quite feeble.