Have you seen the “XOR Blackmail” in the Death in Damascus paper? That’s a much better problem with EDT than the smoking lesion problem, in my view. And it’s simple to describe:
An agent has been alerted to a rumor that her house has a terrible termite infestation, which would cost her $1,000,000 in damages. She doesn’t know whether this rumor is true. A greedy and accurate predictor with a strong reputation for honesty has learned whether or not it’s true, and drafts a letter:
I know whether or not you have termites, and I have sent you this letter iff exactly one of the following is true: (i) the rumor is false, and you are going to pay me $1,000 upon receiving this letter; or (ii) the rumor is true, and you will not pay me upon receiving this letter.
The predictor then predicts what the agent would do upon receiving the letter, and sends the agent the letter iff exactly one of (i) or (ii) is true. Thus, the claim made by the letter is true. Assume the agent receives the letter. Should she pay up?
EDT doesn’t pay if it is given the choice to commit to not paying ex-ante (before receiving the letter). So the thought experiment might be an argument against ordinary EDT, but not against updateless EDT. If one takes the possibility of anthropic uncertainty into account, then even ordinary EDT might not pay the blackmailer. See also Abram Demski’s post about the Smoking Lesion. Ahmed and Price defend EDT along similar lines in a response to a related thought experiment by Frank Arntzenius.
Yes, this demonstrates that EDT is also unstable under self modification, just as CDT is. And trying to build an updateless EDT is exactly what UDT is doing.
Have you seen the “XOR Blackmail” in the Death in Damascus paper? That’s a much better problem with EDT than the smoking lesion problem, in my view. And it’s simple to describe:
EDT doesn’t pay if it is given the choice to commit to not paying ex-ante (before receiving the letter). So the thought experiment might be an argument against ordinary EDT, but not against updateless EDT. If one takes the possibility of anthropic uncertainty into account, then even ordinary EDT might not pay the blackmailer. See also Abram Demski’s post about the Smoking Lesion. Ahmed and Price defend EDT along similar lines in a response to a related thought experiment by Frank Arntzenius.
Yes, this demonstrates that EDT is also unstable under self modification, just as CDT is. And trying to build an updateless EDT is exactly what UDT is doing.