You did a bit more than de-emphasize it in the title!
Also:
Like latitude and longitude, chances are helpful coordinates on our mental map, not fundamental properties of reality.
“Are”?
**Insofar as we assign positive probability to such theories, we should not rule out chance as being part of the world in a fundamental way. **Indeed, we tried to point out in the post that the de Finetti theorem doesn’t rule out chances, it just shows we don’t need them in order to apply our standard statistical reasoning. In many contexts—such as the first two bullet points in the comment to which I am replying—I think that the de Finetti result gives us strong evidence that we shouldn’t reify chance.
The perennial source of confusion here is the assumption that the question is whether chance/probability is in the map or the territory… but the question sidelines the “both” option. If there were
strong evidence of mutual exclusion, of an XOR rather than IOR premise, the question would be appropriate. But there isn’t.
If there is no evidence of an XOR, no amount of evidence in favour of subjective probability is evidence against objective probability, and objective probability needs to be argued for (or against), on independent grounds. Since there is strong evidence for subjective probability, the choices are subjective+objective versus subjective only, not subjective versus objective.
(This goes right back to “probability is in the mind”)
Occams razor isn’t much help. If you assume determinism as the obvious default, objective uncertainty looks like an additional assumption...but if you assume randomness as the obvious default, then any deteministic or quasi deteministic law seems like an additional thing
In general, my understanding is that in many worlds you need to add some kind of rationality principle or constraint to an agent in the theory so that you get out the Born rule probabilities, either via self-locating uncertainty (as the previous comment suggested) or via a kind of decision theoretic argument.
There’s a purely mathematical argument for the Born rule. The tricky thing is explaining why observations have a classical basis—why observers who are entangled with a superposed system don’t go into superposition with themselves. There are multiple aspects to the measurement problem...the existence or otherwise if a fundamental measurement process, the justification the Born rule, the reason for the emergence of sharp pointer states, and reason for the appearance of a classical basis. Everett theory does rather badly on the last two.
If the authors claim that adding randomness in the territory in classical mechanics requires making it more complex, they should also notice that for quantum mechanics, removing the probability from the territory for QM (like Bohmian mechanics) tends to make the the theories more complex.
OK, but people here tend to prefer many worlds to Bohmian mechanics.. it isn’t clear that MWI is more complex … but it also isn’t clear that it is a actually simpler than the alternatives
…as it’s stated to be in the rationalsphere.
You did a bit more than de-emphasize it in the title!
Also:
“Are”?
The perennial source of confusion here is the assumption that the question is whether chance/probability is in the map or the territory… but the question sidelines the “both” option. If there were
strong evidence of mutual exclusion, of an XOR rather than IOR premise, the question would be appropriate. But there isn’t.
If there is no evidence of an XOR, no amount of evidence in favour of subjective probability is evidence against objective probability, and objective probability needs to be argued for (or against), on independent grounds. Since there is strong evidence for subjective probability, the choices are subjective+objective versus subjective only, not subjective versus objective.
(This goes right back to “probability is in the mind”)
Occams razor isn’t much help. If you assume determinism as the obvious default, objective uncertainty looks like an additional assumption...but if you assume randomness as the obvious default, then any deteministic or quasi deteministic law seems like an additional thing
@quiet_NaN
There’s a purely mathematical argument for the Born rule. The tricky thing is explaining why observations have a classical basis—why observers who are entangled with a superposed system don’t go into superposition with themselves. There are multiple aspects to the measurement problem...the existence or otherwise if a fundamental measurement process, the justification the Born rule, the reason for the emergence of sharp pointer states, and reason for the appearance of a classical basis. Everett theory does rather badly on the last two.
OK, but people here tend to prefer many worlds to Bohmian mechanics.. it isn’t clear that MWI is more complex … but it also isn’t clear that it is a actually simpler than the alternatives …as it’s stated to be in the rationalsphere.