Since few people have thought of the Doomsday argument independently, and there is lots of discussion of it, why should one look at individual people? Shouldn’t the reference class be “civilizations” or “intellectual communities”? And then it’s not at all clear that doom is coming anytime soon.
Really, though, the whole idea of picking a “reference class” is just arbitrary, indicating that the whole line of reasoning has no sound basis.
As I said in “Each reference class has its own end”, the problem of reference class is not problem, because for each class there are its own type of the end.
In your example, our civilization started to think about doomsday argument around 1973, almost 50 years ago. And in around 50 years from now we will stop to think about it. It is not necessary a global catastrophe, may be wу will just lose interest. But combined with other forms of DA (birth rank) and other non-DA ideas, like x-risks, it looks like a plausible explanation.
This actually demonstrates the problem further. If using “civilization” as the reference class then as you said humans would stop thinking about DA in about 50 years since it started 50 years ago. But what if we use “people thinking about DA” as the reference class? Due to the internet giving it more exposure, there are a lot more people thinking about DA now than in the 80s and 90s. If I am in the middle of all these people, then we would likely stop thinking about DA a lot sooner.
Similarly, human civilization has existed for about 5000 years so it would exist for another 5000. But for much of history, the global population is way less than a billion. We are likely around the 100 billionths human every born. So if use each person as the reference class then with the population boom the end shall arrive much sooner.
The forecast of the future changes drastically when different reference classes are used. So for DA to be valid there must be an exclusively “correct” reference class. But they all seem arbitrary.
I agree with your prediction: complex civilization capable to think about DA will collapse soon, in a few decades, but some form of medieval civilization can exist a few millennia. It is completely normal and typical outcome, if we ignore hopes on space exploration.
This staged collapse prediction is what follows from the idea that “each reference class has its own end”: for the reference class of DA thinkers the end is nigh. For written civilization it is in few thousands years.
I would regard the world in 1900 as a “complex civilization capable of thinking about DA”. It’s just that nobody bothered to think about it or publish their thoughts. So shouldn’t we expect our society to remain that capability for another 120 years? At the same time, we also expect everyone to stop thinking about DA in 50 years. Because DA has been only discussed for 50 years so far?
For any choice of reference of class to have the same prediction of the future, that prediction would effectively be a mirror image of the past.
I think the very idea of “I am a typical observer” is misguided. Because “observer” is a target drawn around where the arrow is. The arrow is the first person “I” in this analogy.
Everyone knows who the first-person “I” refers to since the only subjective experience felt is due to that particular physical body. We then put physical systems similar to this body into a category, and give it a name. But what similar feature is chosen to perform this grouping is arbitrary. From my personal perspective, such groups can be middle-aged men, things that can do simple arithmetic, synapsids, carbon-based lifeforms, macroscopic physical system, etc. It would be rather absurd to think the first-person “I” is typical for all these groups.
Furthermore, what does “typical” among a group really mean? If we look at the features that define a category, then of course I am similar to everything else. Since this grouping is based on me having that feature in the first place. This gives a false sense of mediocracy. But why would I be typical in terms of other features? e.g. for macroscopic physical systems, the defining feature is its scale, why should I expect myself exist at a typical time for this group? There is no reason for it. Various anthropic camps try to support this by regarding “I” as a random sample of some sort. But that is just adding ad-hoc assumptions.
It is not a coincidence that most anthropic theories have trouble defining what “observer” really means, which in turn messes up the reference class. (This is not exclusive to SSA. SIA and FNC are plagued by it too). Because it has no hard definition. It is just a circle drawn around the first-person “I” with a radius of anyone’s choosing.
Many think “observer” can be conclusively defined as someone/something that is conscious. But what is consciousness in the first place? The only consciousness that anyone has access to is that of the first person. “I know I am conscious, and can never be sure if you are just auto-piloting philosophical zombies.” I guess other people/animals/programs might also be conscious only because of their similarity to myself.
All in all, I feel people who hold “I am a typical observer” as an indisputable truth didn’t take a hard look at what the word “I” or “observer” or “typical” really means.
I think that what you said here and elsewhere could boil down to two different views:
Going from 1 position to 3 position in probabilities sense is ontologically impossible, period. No meaningful probability updates.
We need to take hard look on what is “I”, “observer”, and “typical”, and only after we clearly define them, we could said something meaningful about probabilities.
I tend here to agree with the second view, and I explored different aspects of it in some of my posts.
I’m not sure what 1 position and 3 position mean here. I would summarize my argument as the first-person perspective is based on subjective experience. It is a primitive notion that cannot be logically analyzed. Just like in Euclidean geometry we can’t analyze any of its axioms. Take then as given, that’s it.
All the rest, like no self-locating probability, perspective disagreement, rejection of doomsday argument and presumptuous philosopher, double-halving in sleeping beauty, and rejection of fine-tuned universe, are just conclusions based on that.
Well in that case yes. 3rd person’s perspective is just a shorthand for the perspective of a god’s eye view. We should not switch perspectives halfway in any given analysis.
To get more credible estimates with 90 per cent confidence, it better to take just order of magnitude. In that case, the apparent strange overconfidence of DA predictions dissappears as well as its mirror structure.
So we can say that both ability to think about DA and the thinking about it will exist for several decades.
(Note also that Laplace seems to be the first who was close to DA, and it was in 1801)
It is like Laplace sunrise problem: everyday the sun have risen is a small bit of evidence that it more likely to rise again. The same way if the world didn’t end today, it is a small evidence that allows to extend our expected doomsday date.
I’ve read your linked post, and it doesn’t convince me. The reasoning doesn’t seem rooted in any defensible principles, but is rather just using plausible-sounding heuristics which there is no reason to think will produce consistent results.
The example of the person placed on the unknown-sized grid has a perfectly satisfactory solution using standard Bayesian inference: You have a prior for the number of cells in the row. After observing that you’re in cell n, the likelihood function for there being R rows is zero for R less than n, and 1/R for R greater than or equal to n. You multiply the likelihood by the prior and normalize to get a posterior distribution for R. Observing that you’re in cell 1 does increase the probability of small values for R, but not necessarily in the exact way you might think from a heuristic about needing to by “typical”.
To illustrate the inconsistencies of that heuristic, consider that for as long as humans don’t go extinct, we’ll probably be using controlled fire, the wheel, and lenses. But fire was controlled hundreds of thousands of years ago, the wheel was invented thousands of years ago, and lenses were invented hundreds of years ago. Depending on which invention you focus on, you get completely different predictions of when humans will go extinct, based on wanting us to be “typical” in the time span of the invention. I think none of these predictions have any validity.
“End of the reference class” is not extinction, the class could end in differently. For any question we ask we simultaneously define reference class and what we mean by its ending.
In your example of fire, wheels and lenses: imagine that humanity will experience a very long period civilizational decline. Lens will disappear first, wheels seconds and fire will be the last in million of years. It is a boring but plausible apocalypse.
Possible, sure. But the implication of inference from these reference classes is that this future with a long period of civilizational decline is the only likely one—that some catastrophic end in the near future is pretty much ruled out. Much as I’d like to believe that, I don’t think one can actually infer that from the history of fire, wheels, and lenses.
Since few people have thought of the Doomsday argument independently, and there is lots of discussion of it, why should one look at individual people? Shouldn’t the reference class be “civilizations” or “intellectual communities”? And then it’s not at all clear that doom is coming anytime soon.
Really, though, the whole idea of picking a “reference class” is just arbitrary, indicating that the whole line of reasoning has no sound basis.
As I said in “Each reference class has its own end”, the problem of reference class is not problem, because for each class there are its own type of the end.
In your example, our civilization started to think about doomsday argument around 1973, almost 50 years ago. And in around 50 years from now we will stop to think about it. It is not necessary a global catastrophe, may be wу will just lose interest. But combined with other forms of DA (birth rank) and other non-DA ideas, like x-risks, it looks like a plausible explanation.
This actually demonstrates the problem further. If using “civilization” as the reference class then as you said humans would stop thinking about DA in about 50 years since it started 50 years ago. But what if we use “people thinking about DA” as the reference class? Due to the internet giving it more exposure, there are a lot more people thinking about DA now than in the 80s and 90s. If I am in the middle of all these people, then we would likely stop thinking about DA a lot sooner.
Similarly, human civilization has existed for about 5000 years so it would exist for another 5000. But for much of history, the global population is way less than a billion. We are likely around the 100 billionths human every born. So if use each person as the reference class then with the population boom the end shall arrive much sooner.
The forecast of the future changes drastically when different reference classes are used. So for DA to be valid there must be an exclusively “correct” reference class. But they all seem arbitrary.
I agree with your prediction: complex civilization capable to think about DA will collapse soon, in a few decades, but some form of medieval civilization can exist a few millennia. It is completely normal and typical outcome, if we ignore hopes on space exploration.
This staged collapse prediction is what follows from the idea that “each reference class has its own end”: for the reference class of DA thinkers the end is nigh. For written civilization it is in few thousands years.
I would regard the world in 1900 as a “complex civilization capable of thinking about DA”. It’s just that nobody bothered to think about it or publish their thoughts. So shouldn’t we expect our society to remain that capability for another 120 years? At the same time, we also expect everyone to stop thinking about DA in 50 years. Because DA has been only discussed for 50 years so far?
For any choice of reference of class to have the same prediction of the future, that prediction would effectively be a mirror image of the past.
BTW, what is your opinion about medocrity principle, that is, the idea of typicality of you, me and Earth?
I think the very idea of “I am a typical observer” is misguided. Because “observer” is a target drawn around where the arrow is. The arrow is the first person “I” in this analogy.
Everyone knows who the first-person “I” refers to since the only subjective experience felt is due to that particular physical body. We then put physical systems similar to this body into a category, and give it a name. But what similar feature is chosen to perform this grouping is arbitrary. From my personal perspective, such groups can be middle-aged men, things that can do simple arithmetic, synapsids, carbon-based lifeforms, macroscopic physical system, etc. It would be rather absurd to think the first-person “I” is typical for all these groups.
Furthermore, what does “typical” among a group really mean? If we look at the features that define a category, then of course I am similar to everything else. Since this grouping is based on me having that feature in the first place. This gives a false sense of mediocracy. But why would I be typical in terms of other features? e.g. for macroscopic physical systems, the defining feature is its scale, why should I expect myself exist at a typical time for this group? There is no reason for it. Various anthropic camps try to support this by regarding “I” as a random sample of some sort. But that is just adding ad-hoc assumptions.
It is not a coincidence that most anthropic theories have trouble defining what “observer” really means, which in turn messes up the reference class. (This is not exclusive to SSA. SIA and FNC are plagued by it too). Because it has no hard definition. It is just a circle drawn around the first-person “I” with a radius of anyone’s choosing.
Many think “observer” can be conclusively defined as someone/something that is conscious. But what is consciousness in the first place? The only consciousness that anyone has access to is that of the first person. “I know I am conscious, and can never be sure if you are just auto-piloting philosophical zombies.” I guess other people/animals/programs might also be conscious only because of their similarity to myself.
All in all, I feel people who hold “I am a typical observer” as an indisputable truth didn’t take a hard look at what the word “I” or “observer” or “typical” really means.
I think that what you said here and elsewhere could boil down to two different views:
Going from 1 position to 3 position in probabilities sense is ontologically impossible, period. No meaningful probability updates.
We need to take hard look on what is “I”, “observer”, and “typical”, and only after we clearly define them, we could said something meaningful about probabilities.
I tend here to agree with the second view, and I explored different aspects of it in some of my posts.
I’m not sure what 1 position and 3 position mean here. I would summarize my argument as the first-person perspective is based on subjective experience. It is a primitive notion that cannot be logically analyzed. Just like in Euclidean geometry we can’t analyze any of its axioms. Take then as given, that’s it.
All the rest, like no self-locating probability, perspective disagreement, rejection of doomsday argument and presumptuous philosopher, double-halving in sleeping beauty, and rejection of fine-tuned universe, are just conclusions based on that.
1 position = first-person perspective, 3 position = third-person perspective
Well in that case yes. 3rd person’s perspective is just a shorthand for the perspective of a god’s eye view. We should not switch perspectives halfway in any given analysis.
To get more credible estimates with 90 per cent confidence, it better to take just order of magnitude. In that case, the apparent strange overconfidence of DA predictions dissappears as well as its mirror structure.
So we can say that both ability to think about DA and the thinking about it will exist for several decades.
(Note also that Laplace seems to be the first who was close to DA, and it was in 1801)
[edited]
It is like Laplace sunrise problem: everyday the sun have risen is a small bit of evidence that it more likely to rise again. The same way if the world didn’t end today, it is a small evidence that allows to extend our expected doomsday date.
[edited]
Why?
I’ve read your linked post, and it doesn’t convince me. The reasoning doesn’t seem rooted in any defensible principles, but is rather just using plausible-sounding heuristics which there is no reason to think will produce consistent results.
The example of the person placed on the unknown-sized grid has a perfectly satisfactory solution using standard Bayesian inference: You have a prior for the number of cells in the row. After observing that you’re in cell n, the likelihood function for there being R rows is zero for R less than n, and 1/R for R greater than or equal to n. You multiply the likelihood by the prior and normalize to get a posterior distribution for R. Observing that you’re in cell 1 does increase the probability of small values for R, but not necessarily in the exact way you might think from a heuristic about needing to by “typical”.
To illustrate the inconsistencies of that heuristic, consider that for as long as humans don’t go extinct, we’ll probably be using controlled fire, the wheel, and lenses. But fire was controlled hundreds of thousands of years ago, the wheel was invented thousands of years ago, and lenses were invented hundreds of years ago. Depending on which invention you focus on, you get completely different predictions of when humans will go extinct, based on wanting us to be “typical” in the time span of the invention. I think none of these predictions have any validity.
“End of the reference class” is not extinction, the class could end in differently. For any question we ask we simultaneously define reference class and what we mean by its ending.
In your example of fire, wheels and lenses: imagine that humanity will experience a very long period civilizational decline. Lens will disappear first, wheels seconds and fire will be the last in million of years. It is a boring but plausible apocalypse.
Possible, sure. But the implication of inference from these reference classes is that this future with a long period of civilizational decline is the only likely one—that some catastrophic end in the near future is pretty much ruled out. Much as I’d like to believe that, I don’t think one can actually infer that from the history of fire, wheels, and lenses.