X0: everyone currently alive dies
You may note that this is already the case: we’re all slated for death within a few decades, unless something odd changes that. If we were already personally immortal, I think it’s likely we would regard it as a kind of x-risk - but a less drastic version than the ones below.
X1: no more biological human beings
In this scenario, AIs or other engineered organisms who are psychologically identical to humans - or at least retain everything we find valuable about ourselves psychologically - still exist. However, homo sapiens is extinct.
X2: no more humanlike minds
In this scenario, there might still be intelligent beings with complex inner experiences, but they’re not like humans. The boundaries between X2 and X3 are a sliding scale: one can imagine ablating sexual desire, then fear of death, then various the cognitive biases… while adding electromagnetic senses, the ability to think intuitively in more dimensions… each step perhaps a Pareto improvement to all lights, but leading towards something so unlike ourselves that it might as well be as if humans had gone extinct and, several million years later, octopodes had developed a complex civilization. Such a world would still have tremendous value, but from our perspective, something very valuable and precious would have been lost.
If there are other intelligent civilizations in our light cone, then the extinction of life on earth has a catastrophic limit here: the Zzalph Confederacy of Taurus B will carry on the light of consciousness and civilization without us. If not - or if we create a non-conscious expansionary process, like a swarm of devouring von Neumann probes - then what we do here could bring us into yet deeper catastrophe.
X3: no more sapience
In this scenario, there is nothing left that can feel and reflect upon its own experiences and make decisions in light of that: only animals, or not-quite-complex-enough computer programs, or hedonium.
I think this is pretty bad, for obvious reasons: I hope we survive, and I hope the Zzalph Confederacy survives for their own sake, but conditional on our dying out with no sapient successors I really hope the plucky Zzalphs live on, stuck carrying forward (some of) our hopes and dreams without knowing it.1
How bad this is depends on the experiences that are left: the S-risk carried by lots of animal-like minds, the potential upside of hedonium. A universe of hedonium would be a pathetic shame, but certainly better than a universe of suffering, or one of…
X4: no more subjective experience
This is a universe of no value. No value except that value might arise here, in some way, except…
X5: no more possibility of subjective experience arising
An expansionary, optimizing-but-not-sapient cloud of Blindsight scamblers or von Neumann probes would, if stable enough, be able to extinguish the possibility of anything more interesting arising. This is the True Death, from which nothing more can be wrested.
We are remarkably early in the history of the universe, so probably not: but imagine a scenario where we are the last of several civilizations, all of the others of whom died in some terrible mistake or coordination failure… how great our responsibility to get this right, even relative to before!
Interesting article. Certainly, a world without subjective experience and second order values would be “valueless” as we understand that term to be, as I believe (and will argue) that values are based on conscious reflection.
Yet I wouldn’t describe such a world as “bad” since such a world would be empty of “good” and “bad.” It’s an unsettling thought certainly, like death typically is, but I wouldn’t view that world as any more bad as the world “before” there was any conscious life.
It’s like the stoic’s conception of death. Presumably you didn’t care about your non-existence before you were born, so why does your non-existence matter after your birth?