Ethical Cartesianism

In general I tend to dislike arguments in which the phrases 'moral status' or 'moral significance' occur; such stilted, jargonish, roundabout phrases are usually a tip-off that we are about to be subjected to a truly dimwitted argument, glossed over with a phrase that, because pedantic, looks precise while it is really, because unspecific, imprecise and full of equivocation. Even fairly sophisticated attempts to use such concepts quickly begin to break down, and the arguments that founder on it are truly legion. This is especially true when it is used in debates over abortion.
Independently of any problems with the term itself, we should be careful of descriptions of pro-life positions that use the phrase 'moral status'; it tends to be much more popular among pro-choicers describing pro-life views than among pro-lifers describing their own views, which should raise red flags.

But I thought Richard's post, Pro-Life, Pro-Zombie?, was somewhat interesting, despite using 'moral status' as the linchpin; possibly, depending on what precisely was meant by the term, it could be reworked without it.

Many pro-lifers hold that an individual has moral status in virtue of its biological kind (being "human") rather than its particular cognitive qualities (being a self-aware "person"). But then, our counterparts in the zombie world are presumably still biologically human. They're physically identical to us, after all, and biology supervenes on physics. As far as biologists are concerned, they are "individual human lives" the same as you and me. So the bio-focused pro-lifer would seem committed to the view that non-conscious zombies have moral status. But that's absurd. (At least, it's absurd to think that they have anything like the kind of moral importance that conscious people do. Maybe complex physical structures can have a kind of value, like ant colonies, or New Zealand's pancake rocks. But I assume the pro-lifer wants to make a stronger claim than that embryos have the value of ants and rocks.)

I think it's a bit obscure here why non-conscious philosophical zombies would lack 'moral status' (however that may be glossed, or perhaps precisely because it is unclear how it should be glossed here). And this is perhaps what struck me as interesting about the argument, because it really is a revival of Cartesian animal-machine arguments in ethics, on new ground. And that is interesting in itself. (I also think Richard underestimates how much, in this day and age, many pro-lifers would be glad even to achieve agreement with some pro-choicers that embryos at least have some kind of value independently of their usefulness to someone.)