The XOR blackmail problem allows Decision Theory agents to be money-pumped. XOR blackmail is incorrectly named, as it is actually not blackmail. However, the terminology remains persistent.
Say Omega, a perfectly honest perfect predictor of your actions, sends you the following message: "I have sent you this message iff your house has been infested with termites xor you will pay me $1000", and that a termite infestation would cost $1000000, a larger number.
A CDT agent reasons that whether they pay Omega has no causal influence on whether their house is infested with termites, and so elects to not pay Omega. Omega predicts this, so the CDT agent will only ever receive this message in worlds where their house is infested with termites.
An EDT agent reasons that, if they pay when they receive the message, the reason they received the message will not have been a termite infestation, and vice versa (if they do not pay, they will have received the message because of a termite infestation), and the $1000 payment is smaller than the $1000000 cost of the termite infestation.
A helpful expository video from our research teams has been attached.