Disclaimer: I preemptively appologize if my comment appears to be rude. I’m writing a series on anthropics due to the fact that I’ve been passionately dissatisfied with the level of discussion on the topic for a long time. Any strong emotions that you may read from this comment are not targeted at you in particular, but at the general way people tend to reason about these matter.
A common way people tend to justify SIA and all it ridiculousness is by pointing at SSA ridiculousness and claiming that it’s even more ridiculous. Frankly, I’m quite tired of this kind of anthropical whataboutism. It seems to be some kind of weird selective blindness. In no other sphere of knowledge people would accept this as a valid reasoning. But in anthropics, somehow, it works?
The fact that SSA is occasionally stupid doesn’t justify SIA’s occasional stupidity. Both are obviously wrong in general, even though sometimes both may produce correct result. You don’t even need to construct any specific mind experiments to show it. Just think about the main assumptions of them for five minutes:
SIA claims that an observer should reason as if they are randomly selected from the set of all possible observers.
SSA claims that an observer should reason as if they’re randomly selected from all actual observers in your reference class.
SIA fails in cases where observer isn’t selected from all possible observers and SSA fails in cases where observer isn’t selected from all actual observers. Obviously. They are not actually opposite. Why would people assume that either one or the other necessary has to be the case? To what law of the universe do they appeal?
The alternatives to SIA are wholly untenable.
As soon as you stop thinking in “either SIA or SSA” mode, an alternative immediately comes to mind:
An observer should reason as if they’re randomly selected from all actual observers if they are actually randomly selected from actual observers and should reason as if they’re randomly selected from the set of all possible observers if they are actually selected from the set of all possible observers.
Or, basically the same idea:
An observer should investigate the causal process that created them and reason accordingly to it, instead of just assuming things for no reason.
Here I’m leaving a link to my post Conservation of Expected Evidence and Random Sampling in Anthropics. It explains how to use this principle on practice and also why “just being a bayesian about the fact that one exists” can be a bad idea in some cases, leading to contradicting the law of conservation of expected evidence. Previous and next posts are also relevant.
Disclaimer: I preemptively appologize if my comment appears to be rude. I’m writing a series on anthropics due to the fact that I’ve been passionately dissatisfied with the level of discussion on the topic for a long time. Any strong emotions that you may read from this comment are not targeted at you in particular, but at the general way people tend to reason about these matter.
A common way people tend to justify SIA and all it ridiculousness is by pointing at SSA ridiculousness and claiming that it’s even more ridiculous. Frankly, I’m quite tired of this kind of anthropical whataboutism. It seems to be some kind of weird selective blindness. In no other sphere of knowledge people would accept this as a valid reasoning. But in anthropics, somehow, it works?
The fact that SSA is occasionally stupid doesn’t justify SIA’s occasional stupidity. Both are obviously wrong in general, even though sometimes both may produce correct result. You don’t even need to construct any specific mind experiments to show it. Just think about the main assumptions of them for five minutes:
SIA claims that an observer should reason as if they are randomly selected from the set of all possible observers.
SSA claims that an observer should reason as if they’re randomly selected from all actual observers in your reference class.
SIA fails in cases where observer isn’t selected from all possible observers and SSA fails in cases where observer isn’t selected from all actual observers. Obviously. They are not actually opposite. Why would people assume that either one or the other necessary has to be the case? To what law of the universe do they appeal?
As soon as you stop thinking in “either SIA or SSA” mode, an alternative immediately comes to mind:
An observer should reason as if they’re randomly selected from all actual observers if they are actually randomly selected from actual observers and should reason as if they’re randomly selected from the set of all possible observers if they are actually selected from the set of all possible observers.
Or, basically the same idea:
An observer should investigate the causal process that created them and reason accordingly to it, instead of just assuming things for no reason.
Here I’m leaving a link to my post Conservation of Expected Evidence and Random Sampling in Anthropics. It explains how to use this principle on practice and also why “just being a bayesian about the fact that one exists” can be a bad idea in some cases, leading to contradicting the law of conservation of expected evidence. Previous and next posts are also relevant.