eg The solution you propose of having some probability threshold below which we can ignore more speculative risks also has many issues. For instance, this would seem to invalidate many arguments for the rationality of voting or for political advocacy, such as canvassing for Corbyn or Sanders: the expected value of such activities is high even though the payoff is often very low (eg <1 in 10 million in most US states). Advocating for degrowth also seems extremely unlikely to succeed given the aims of governments across the world and the preferences of ordinary voters.
You seem to assume that voting / engaging in political advocacy are all obviously important things to do and that any argument that says don’t bother doing them falls prey to a reductio ad absurdum, but it’s not clear to me why you think that.
If all of these actions do in fact have incredibly low probability of positive payoff such that one feels they are in a Pascal’s Mugging when doing them, then one might rationally decide not to do them.
Or perhaps you are imagining a world in which loads of people stop voting such that democracy falls apart. At some point in this world though I’d imagine voting would stop being a Pascal’s Mugging action and would be associated with a reasonably high probability of having a positive payoff.
One reason it might be a reductio ad absurdum is that it suggests that in an election in which supporters of one side were rational (and thus would not vote, since each of their votes would have a minuscule chance of mattering) and the others irrational (and would vote, undeterred by the small chance of their vote mattering), the irrational side would prevail.
If this is the claim that John G. Halstead is referring to, I regard it as a throwaway remark (it’s only one sentence plus a citation):
For instance, a simple threshold or plausibility assessment could protect the field’s resources and attention from being directed towards highly improbable or fictional events.
You seem to assume that voting / engaging in political advocacy are all obviously important things to do and that any argument that says don’t bother doing them falls prey to a reductio ad absurdum, but it’s not clear to me why you think that.
If all of these actions do in fact have incredibly low probability of positive payoff such that one feels they are in a Pascal’s Mugging when doing them, then one might rationally decide not to do them.
Or perhaps you are imagining a world in which loads of people stop voting such that democracy falls apart. At some point in this world though I’d imagine voting would stop being a Pascal’s Mugging action and would be associated with a reasonably high probability of having a positive payoff.
One reason it might be a reductio ad absurdum is that it suggests that in an election in which supporters of one side were rational (and thus would not vote, since each of their votes would have a minuscule chance of mattering) and the others irrational (and would vote, undeterred by the small chance of their vote mattering), the irrational side would prevail.
If this is the claim that John G. Halstead is referring to, I regard it as a throwaway remark (it’s only one sentence plus a citation):