The following are excerpts from notes that I wrote while reading X-Risk by Thomas Moynihan, which have a lot to do with Rawlette's project as well. So I split them off into this file, to be somewhere between both projects.
Perhaps later in the book [this was written after reading up to p. 95 of X-Risk], Moynihan will propose moral realism. I can offer a theistic moral realism, but he wouldn't offer that. He might like Rawlette's. Does hers successfully motivate a person to take responsibility for the extension of value? At least, should it motivate people inclining to civilization-scale nihilism?
I can see Rawlette perhaps making the case that value and disvalue are reliably found in the phenomenology of goodness and badness. Whether we have any duty to maximize them, though, as opposed to a reason to prefer them, I don't know.
On further thought, I think that Rawlette's moral realism would convince some unconvinced people to care about X-risk, on the basis of reason. But it does not argue for one of its important foundations, which is: how is it that a person has any moral accountability to external reality? In simantist terms, why do I have any moral accountability to what is not-me? Not-me including "I need to respond to pain or pleasure" or "I need to respond to threats to my survival" or "Reality all adds up, so I need to do math -- aggregation -- to be moral" or "I need to actually look at my present state of affairs and projected future states of affairs and compare them, bringing myself into them". I am relating to the not-me things of: pain, pleasure, survival, possibility of death, external reality in general, aggregation, present situation, future possibilities. Do I have to relate to those things? [For the sake of this paragraph, I'll call them "the List".] Why should I, if I don't want to? This is a hard problem, one which I think even God can't solve without overriding human free will. But just as Rawlette's theory makes inroads on the problem, I think a theistic moral realism can make further inroads by saying that ought itself is real, has ontological grounding as one of God's limbs, as it were, one of his opinions. If we compare tradition, caprice, tyranny, preaching, or even the tyranny of the nature of pain and pleasure, or even badness and goodness themselves, which are the things to which we must give up our freedom on a secular account, and on the other hand an unshaming God who suffers the same degradations we do, then I can see that some people would be motivated to trust the foundational concepts (or, simantic words) that lead to morality, mentioned above [i.e., the List], who wouldn't by the best secular metaethics. And where secular metaethics tends to (maybe not in the case of Rawlette, I'm not sure) say "hey, if every human on earth wants to slack off and call it an existence and let things run down" [then that's fine], theistic metaethics says "The collective opinion of the human race is not the only one that matters, and we need to do our best, whatever that cashes out to be as theists".
This last point raises a question: what is the theistic take on X-risk?
[I should probably write a longer post on this (I did), but basically, the MSLN take might be "For some reason (certainly this is biblical), God works through, may even have to work through, evolving civilization. Our civilization, believe it or not, is better from his perspective in some important way than the past. Maybe we are getting close to the world in which hardening is minimized. So to throw all of that away to try to start fresh could be costly from his perspective, and so we should value our own civilization and make it more something that minimizes hardening.]
Some people can at least ask "Should I take aggregation, pain, pleasure, etc. seriously?" If they can still ask this question, they are still concerned about "should" or "ought" of some sort. A case can [or might] be made that God is true ought, that all that is is ought, that what ought to be is, and that what ought not to be is the clash between two things that ought to be. And this ought that could be taken to [be] being above God is God himself. If we are interested in reality outside ourselves, we can come by reasonable ideas about the nature of God, and these inform our metaethics. [Any real should, including the should in "Should I take aggregation, pain, pleasure, etc. seriously?" (which is "What is to be done, according to should"), must be in tune with God, who can be partially known.] This might be an inroad on nihilism, waking up people if they have the barest connection to should. [To claim that ought fundamentally is, the evidence coming from the called-for-ness of asking the "should?" question.] If it is possible to be rational at all, "should" is involved, and thus excellence is called for apart from human judgment.
A person comes to value their life because they choose to live in the face of unbearable experiences. Once they value their life, they come to value what furthers their life and this includes reason. If God exists (one who lives in the face of much greater unbearability than any one human), then there exists a being who cares more than we do, even if some future human race drops out of concern with reality. If this dropping out is because we will have all rejected God, and thus desire to have no responsibility to him, if reality should require it of us, then he may leave us in our hardenedness, before destroying us. But if our nihilism is not an expression of our enmity with God, he will restore us somehow, perhaps with a healthy dose of unbearability, to challenge us to exist, or reach into our personal beings directly to change us, so that we can begin to relate to him and other beings in a deep way once again.