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.
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.