The three critical probabilities here are Pr(Someone makes an epistemic mistake when thinking about their place in history), Pr(Someone believes they live at the HoH|They haven’t made an epistemic mistake), and Pr(Someone believes they live at the HoH|They’ve made an epistemic mistake).
I think the more decision relevant probabilities involve “Someone believes they should act as if they live at the HoH” rather than “Someone believes they live at the HoH”. Our actions may be much less important if ‘this is all a dream/simulation’ (for example). We should make our decisions in the way we wish everyone-similar-to-us-across-the-multiverse make their decisions.
As an analogy, suppose Alice finds herself getting elected as the president of the US. Let’s imagine there are 10100 citizens in the US. So Alice reasons that it’s way more likely that she is delusional than she actually being the president of the US. Should she act as if she is the president of the US anyway, or rather spend her time trying to regain her grip on reality? The 10100 citizens want everyone in her situation to choose the former. It is critical to have a functioning president. And it does not matter if there are many delusional citizens who act as if they are the president. Their “mistake” does not matter. What matters is how the real president acts.
I think the more decision relevant probabilities involve “Someone believes they should act as if they live at the HoH” rather than “Someone believes they live at the HoH”. Our actions may be much less important if ‘this is all a dream/simulation’ (for example). We should make our decisions in the way we wish everyone-similar-to-us-across-the-multiverse make their decisions.
As an analogy, suppose Alice finds herself getting elected as the president of the US. Let’s imagine there are 10100 citizens in the US. So Alice reasons that it’s way more likely that she is delusional than she actually being the president of the US. Should she act as if she is the president of the US anyway, or rather spend her time trying to regain her grip on reality? The 10100 citizens want everyone in her situation to choose the former. It is critical to have a functioning president. And it does not matter if there are many delusional citizens who act as if they are the president. Their “mistake” does not matter. What matters is how the real president acts.