I occasionally see a question like "what would FDT recommend in ....?" and I am puzzled that there is no formal algorithm to answer it. Instead humans ask other humans, and the answers are often different and subject to interpretation. This is rather disconcerting. For comparison, you don't ask a human what, say, a chessbot would do in a certain situation, you just run the bot. Similarly, it would be nice to have an "FDTbot" one can feed a decision theory problem to. Does something like that exist? If not, what are the obstacles?

Just to follow up on that third point a little more: FDT depends upon counterfactual responses, how you

would haveresponded to inputs that you didn't in fact observe.If you go into a scenario where you can observe even as little as 6 bits of information, then there are 2^6 = 64 possible inputs to your decision function. FDT requires that you adopt the function with the greatest expected value over the weighted probabilities of

everyinput, not just the one you actually observed. In the simplest possible case, each output is just one of two deterministic a... (read more)