I’m not entirely persuaded by doomsday arguments (yet) either, but it does seem that there’s an easy answer to your point about the ancient cult. Suppose doom is coming soon for us, but people throughout history have been believing falsely that the doomsday argument applied to them. In that case still the vast majority of people who applied doomsday reasoning throughout time will turn out to have been correct, because now there are so many of us!
(P.S. I don’t think I understood the point about us being delusional—where did that come from?)
The delusional part was a reference to a comment in the op about deluded worlds, where empiricism isn’t valid regardless of all else. Imagine, for example, a universe in which you’re the only person, living an elaborate delusion that you’re actually interacting with other minds. The entire argument collapses in meaninglessness.
And a quick Google search suggests currently living humans only constitute around 10% of all human beings which have ever lived, so there’s a 90% chance that any given believer is incorrect. At what point it becomes correct depends on population dynamics which I hesitate to forecast into the future (except that it’s going to remain valid for at least the next century, provided the birth rate doesn’t rise considerably).
But none of this gives you any additional information about whether or not doomsday is in fact correct—even if it were accurate about the population, and it told you that most people who believe in doomsday are correct, it doesn’t give you any information about whether or not you personally are correct. There’s no new information contained there to update your existing knowledge upon.
You didn’t prove anything. How is our situation now (compared with a galaxy-wide human civilization) different than the caveman (vs. today)? How do we know the ‘vast majority’ of humans are not still in the future, yet to be born?
How is our situation now (compared with a galaxy-wide human civilization) different than the caveman (vs. today)?
The difference is that we exist, whereas a galaxy-wide human civilization may or may not exist in the future.
How do we know the ‘vast majority’ of humans are not still in the future, yet to be born?
We don’t know that, but this is what the doomsday argument provides evidence for.
In general, statistical arguments only work in most cases, not in all cases, so the fact that the first 1% of people would have been misled by the doomsday argument does not show that the doomsday argument is flawed.
The difference is that we exist, whereas a galaxy-wide human civilization may or may not exist in the future.
That’s exactly my point—the caveman could make the same argument: “we hunter-gather tribes exist, whereas a planet-wide civilization of 7 billion human beings may or may not exist in the future.”
In general, statistical arguments only work in most cases, not in all cases, so the fact that the first 1% of people would have been misled by the doomsday argument does not show that the doomsday argument is flawed.
Doomsday will come, whether it is around the corner or 120 billion years from now in the heat-death of the universe. At some point some group of humans will correct in believing the end is nigh. But that is not to say that by the OP’s anthropic reasoning they would be justified in believing so. Rather, a broken clock is still right twice a day.
That’s exactly my point—the caveman could make the same argument: “we hunter-gather tribes exist, whereas a planet-wide civilization of 7 billion human beings may or may not exist in the future.”
And your point has been countered with “although the caveman would have been wrong, most people in history who made the argument would have been right, for which reason the caveman would have been justified in making that argument”, which you haven’t addressed.
If you have to choose between guessing “this fair six-sided die will produce a six on its next roll” or “this fair six-sided die will produce a non-six on its next roll”, then the latter alternative is the right one to pick since it maximizes your chance of being correct. Yes, you know for certain that this guess will turn out to be wrong in one sixth of the cases, but that doesn’t mean that the math of “choosing non-six maximizes your chance of being right” would be wrong.
Similarly, we know that of everyone who could make the Doomsday Argument, some percentage (depending on the specifics of the argument) will always be wrong, but that doesn’t mean that the math of the Doomsday Argument would be wrong.
I’m not entirely persuaded by doomsday arguments (yet) either, but it does seem that there’s an easy answer to your point about the ancient cult. Suppose doom is coming soon for us, but people throughout history have been believing falsely that the doomsday argument applied to them. In that case still the vast majority of people who applied doomsday reasoning throughout time will turn out to have been correct, because now there are so many of us!
(P.S. I don’t think I understood the point about us being delusional—where did that come from?)
The delusional part was a reference to a comment in the op about deluded worlds, where empiricism isn’t valid regardless of all else. Imagine, for example, a universe in which you’re the only person, living an elaborate delusion that you’re actually interacting with other minds. The entire argument collapses in meaninglessness.
And a quick Google search suggests currently living humans only constitute around 10% of all human beings which have ever lived, so there’s a 90% chance that any given believer is incorrect. At what point it becomes correct depends on population dynamics which I hesitate to forecast into the future (except that it’s going to remain valid for at least the next century, provided the birth rate doesn’t rise considerably).
But none of this gives you any additional information about whether or not doomsday is in fact correct—even if it were accurate about the population, and it told you that most people who believe in doomsday are correct, it doesn’t give you any information about whether or not you personally are correct. There’s no new information contained there to update your existing knowledge upon.
You didn’t prove anything. How is our situation now (compared with a galaxy-wide human civilization) different than the caveman (vs. today)? How do we know the ‘vast majority’ of humans are not still in the future, yet to be born?
The difference is that we exist, whereas a galaxy-wide human civilization may or may not exist in the future.
We don’t know that, but this is what the doomsday argument provides evidence for.
In general, statistical arguments only work in most cases, not in all cases, so the fact that the first 1% of people would have been misled by the doomsday argument does not show that the doomsday argument is flawed.
That’s exactly my point—the caveman could make the same argument: “we hunter-gather tribes exist, whereas a planet-wide civilization of 7 billion human beings may or may not exist in the future.”
Doomsday will come, whether it is around the corner or 120 billion years from now in the heat-death of the universe. At some point some group of humans will correct in believing the end is nigh. But that is not to say that by the OP’s anthropic reasoning they would be justified in believing so. Rather, a broken clock is still right twice a day.
And your point has been countered with “although the caveman would have been wrong, most people in history who made the argument would have been right, for which reason the caveman would have been justified in making that argument”, which you haven’t addressed.
If you have to choose between guessing “this fair six-sided die will produce a six on its next roll” or “this fair six-sided die will produce a non-six on its next roll”, then the latter alternative is the right one to pick since it maximizes your chance of being correct. Yes, you know for certain that this guess will turn out to be wrong in one sixth of the cases, but that doesn’t mean that the math of “choosing non-six maximizes your chance of being right” would be wrong.
Similarly, we know that of everyone who could make the Doomsday Argument, some percentage (depending on the specifics of the argument) will always be wrong, but that doesn’t mean that the math of the Doomsday Argument would be wrong.
Hmm… good point!
We know stuff the caveman didn’t, so P(exactly n people will ever live | what we know) != P(exactly n people will ever live | what the caveman knew).