The problem is that by declaring something “Absurd” you’re making a very strong bet against it. You’re going to lose a fair number of these bets.
Suppose calling something absurd merely means it’s 1% probable. If you’re right about that 90% of the time, each one you get wrong costs you a factor of 10 on your accuracy, far more than you gain from ascribing the extra 9% probability to the other 9 cases you happened to be right. And 1% is high enough few would call it truly absurd.
Calling something absurd is asking to be smacked hard (in terms of accuracy) if you’re wrong—and feeling safe about it.
Bringing myself back to what I was thinking in 2007 -- I think we have some semantic confusion around two different sense of absurdity. One is the heuristic Eliezer discusses—the determination of whether a claim/prediction has surface plausibility. If not we file it under “absurd”. An absurdity heuristic would be some heuristic which considers surface plausibility or lack thereof as evidence for or against a claim.
On the other hand, we have the sense of “Absurd!” as a very strong negative claim about something’s probability of truth. So “Absurd!” stands in for “less than .01/.001/whatever”, instead of a term such as “unlikely” which might mean “less than .15”
I was talking only about the first sense. It seemed to me that Eliezer was making a very strong claim that the absurdity heuristic (in the first sense) does no better than maximum entropy. That’s equivalent to saying that surface plausibility or lack thereof amounts to zero evidence. That allowing yourself to modify probabilities downward due to “absurdity” even a small amount would be an error.
I strongly doubt that this is the case.
I agree completely that a claim of “Absurd!” in the second sense about a long-dated future prediction cannot ever be justified merely by absurdity in the first sense.
The problem is that by declaring something “Absurd” you’re making a very strong bet against it. You’re going to lose a fair number of these bets.
Suppose calling something absurd merely means it’s 1% probable. If you’re right about that 90% of the time, each one you get wrong costs you a factor of 10 on your accuracy, far more than you gain from ascribing the extra 9% probability to the other 9 cases you happened to be right. And 1% is high enough few would call it truly absurd.
Calling something absurd is asking to be smacked hard (in terms of accuracy) if you’re wrong—and feeling safe about it.
Bringing myself back to what I was thinking in 2007 -- I think we have some semantic confusion around two different sense of absurdity. One is the heuristic Eliezer discusses—the determination of whether a claim/prediction has surface plausibility. If not we file it under “absurd”. An absurdity heuristic would be some heuristic which considers surface plausibility or lack thereof as evidence for or against a claim.
On the other hand, we have the sense of “Absurd!” as a very strong negative claim about something’s probability of truth. So “Absurd!” stands in for “less than .01/.001/whatever”, instead of a term such as “unlikely” which might mean “less than .15”
I was talking only about the first sense. It seemed to me that Eliezer was making a very strong claim that the absurdity heuristic (in the first sense) does no better than maximum entropy. That’s equivalent to saying that surface plausibility or lack thereof amounts to zero evidence. That allowing yourself to modify probabilities downward due to “absurdity” even a small amount would be an error.
I strongly doubt that this is the case.
I agree completely that a claim of “Absurd!” in the second sense about a long-dated future prediction cannot ever be justified merely by absurdity in the first sense.