Does anyone own "The Moral Landscape"?

[DLJ]

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I laid out four positions of moral skepticism. If you'd adopt one to defend, we can have a debate. If you agree with more than one brand of moral skepticism, that's fine too. But let us treat them one at a time.

Did you mean these?

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So there are two main branches of moral skepticism: relativism and nihilism. One way to determine if moral facts are real or not is to examine all the types of moral skepticism and see if they are "runaway skepticism" or not. Each branch has two main offshoots:

MORAL RELATIVISM
Cultural relativism: the view that moral values are only a construct of one's overarching culture [James Rachels successfully argued against this IMO, but if it is still a thing with you, we can discuss it.]

Individual relativism: the view that what ever one personally thinks right/wrong is all there is to morality.

MORAL NIHILISM

Error theory: Moral statements are in fact misstatements. They are errors. Just like when someone says "The grace of God carried me through the proceedings" they aren't talking about anything real, when I say "Murder is immoral." I am (similarly) not talking about anything real.

Expressivism: Moral statements are actually emotional expressions. When I say "Murder is wrong." What I'm really saying is "Murder--yuck!" or "Murder--blehhhh!"

So which mode of moral skepticism do you find most compelling? In order for me to defend moral realism, I need to know where you're coming from. You sound a bit like an error theorist, but I figured I'd lay them all out just so we could be clear before proceeding.

What if they are all partially valid and invalid or, as the Catuṣkoṭi would have it: P and not P?