Comment author:VincentYu
23 November 2012 04:32:14PM
*
4 points
[-]

Dialogue 2 and dialogue 3 as you phrased them are equivalent, but they both omit a significant aspect of the original discussion -- that Omega promises that if the coin had come up tails, it would have offered the same bet (which would now have been a winning one for you).

Mmm... I implied it by saying in the first paragraph that Omega is reliable and that's common knowledge, but it's true that the wording could have been much clearer. I wonder if an edit would do more harm than good.

Common knowledge of Omega's reliability is not sufficient. ArisKatsaris is pointing out that in your current post, Omega is allowed to condition its offer on the outcome of the coin flip. The original discussion on counterfactual mugging specifies that this is not allowedâ€”Omega's offer is independent of the coin flip.

Your scenarios, as stated, leave it unclear whether the bet is offered because it came up heads. So the possibility is left open that Omega only offer bets when he knows that the coin came up heads.

That's on purpose, and is exactly the information that the agent doesn't have in one-shot counterfactual mugging.

You do have the information. In counterfactual mugging, Omega tells you truthfully (with its trustworthiness being common knowledge) that it would have given the same offer if the coin had landed differently.

Comment author:MrMind
26 November 2012 02:42:40PM
0 points
[-]

Common knowledge of Omega's reliability is not sufficient. ArisKatsaris is pointing out that in your current post, Omega is allowed to condition its offer on the outcome of the coin flip. The original discussion on counterfactual mugging specifies that this is not allowedâ€”Omega's offer is independent of the coin flip.

You do have the information. In counterfactual mugging, Omega tells you truthfully (with its trustworthiness being common knowledge) that it would have given the same offer if the coin had landed differently.

I'm starting to think that there's a deeper-than-I-thought point about the extraction of this information from the way I structured the dialogue. If all that Omega offers is a series of bet, and the TDT agent has no information about what would have Omega done if the coin toss came out differently or even if he will see Omega again, then it's not clear to me what a TDT agent should do.

If all that Omega offers is a series of bet, and the TDT agent has no information about what would have Omega done if the coin toss came out differently or even if he will see Omega again, then it's not clear to me what a TDT agent should do.

Indeed. I think that's why it's sometimes better to imagine "Omega" as some sort of stable physical process whose complete functionality we know, instead of an as an agent with mysterious motivations.

## Comments (8)

Best*4 points [-]Common knowledge of Omega's reliability is not sufficient. ArisKatsaris is pointing out that in your current post, Omega is allowed to condition its offer on the outcome of the coin flip. The original discussion on counterfactual mugging specifies that this is not allowedâ€”Omega's offer is independent of the coin flip.

You

dohave the information. In counterfactual mugging, Omega tells you truthfully (with its trustworthiness being common knowledge) that it would have given the same offer if the coin had landed differently.I'm starting to think that there's a deeper-than-I-thought point about the extraction of this information from the way I structured the dialogue. If all that Omega offers is a series of bet, and the TDT agent has no information about what would have Omega done if the coin toss came out differently or even if he will see Omega again, then it's not clear to me what a TDT agent should do.

Indeed. I think that's why it's sometimes better to imagine "Omega" as some sort of stable physical process whose complete functionality we know, instead of an as an agent with mysterious motivations.