The arguments by Bostrom, Yudkowsky and others can be summarised as follows:
- Superintelligence is possible
- We don't know how to align a superintelligence
- An unaligned superintelligence could be catastrophically dangerous
I'm not sure if premise 1 is falsifiable, but it is provable. If someone either develops an AI with greater intelligence than a human, or discovers an alien with same, or provides proof through information theory or other scientific knowledge that greater-than-human intelligence is possible, then premise 1 is proven. (Someone more qualified than me: is this already proven?)
Premise 2 is falsifiable: if you can prove that some method will safely align a superintelligence then you have disproved the claim. To date, no one understands intelligence well enough to come up with such a proof, despite a lot of effort by people like Yudkowski, but the claim is not unfalsifiable in principle.
Admittedly premise 3 is less falsifiable, because it's a claim about risk (an unaligned superintelligence could be very dangerous, not definitely 100% will be). But to disagree with premise 3 you have to believe that an unaligned super-intelligence is definitely safe. Either you claim that no superintelligence of any alignment will ever be dangerous or you claim that humanity will always be able to restrain a rogue superintelligence. Neither of those are the sort of claim you could reasonably consider to be 100% certain.
At this point, we're down to debates about how large the risk is, and IMO that explains why Yudkowsky and Bostrom give lots of different scenarios, as a counter-argument to people who want to assume that only certain narrow paths lead to catastrophe.
If on the onset there is a rejection of binary falsifiability then the argumentation Bostrom uses of disjunctive arguments with conjecture makes total sense, since every disjunction can only add to the total probability of it being true. Disproving each independent argument can then also not be done in a binary way, i.e. we can only decrease its probability.
Changing the minds would be to decrease the probability of the (collective) argument to a point where it becomes not worth considering, yet, as Templarrr stated, any nonzero chance of extinction (for which preventative action could be undertaken) would be worth considering. Looking at it from this perspective there must be binary falsification because any chance greater than 0 makes the argument 'valid', i.e. worth considering.
I am assuming there are a lot, perhaps contrived, cases of nonzero chance of extinction with possible preventative action which would sound preposterous to undertake compared to AI alignment (either for their absurdly low chance or absurdly high cost to undertake). Those do not interest me; rather I wonder if this is perceived as an actual problem and why/why not? I have no clue why it would not be a problem (maybe that's where the contrived examples come in) and maybe it would not be a problem as it is definitive proof that they are right. The latter point I find very unconvincing, so I hope there are some better refutations at hand within the community.
P.S. thanks for the recommendation, I will check what Joseph Carlsmith has written.