I think this is an interesting objection. E.g., “if you’re into EDT ex ante, shouldn’t you be into EDT ex post, and say that it was a ‘good action’ to learn about the Egyptians, because you learned that they were better off than you thought in expectation?” I think it depends, though, on how you are doing the ex post evaluation: and the objection doesn’t work if the ex post evaluation conditions on the information you learn.
That is, suppose that before you read Wikipedia, you were 50% on the Egyptians were at 0 welfare, and 50% they were at 10 welfare, so 5 in expectation, but reading is 0 EV. After reading, you find out that their welfare was 10. OK, should we count this action, in retrospect, as worth 5 welfare for the Egyptians? I’d say no, because the ex post evaluation should go: “Granted that the Egyptians were at 10 welfare, was it good to learn that they were at 10 welfare?”. And the answer is no: the learning was a 0-welfare change.
That is, suppose that before you read Wikipedia, you were 50% on the Egyptians were at 0 welfare, and 50% they were at 10 welfare, so 5 in expectation, but reading is 0 EV. After reading, you find out that their welfare was 10. OK, should we count this action, in retrospect, as worth 5 welfare for the Egyptians? I’d say no, because the ex post evaluation should go: “Granted that the Egyptians were at 10 welfare, was it good to learn that they were at 10 welfare?”. And the answer is no: the learning was a 0-welfare change.
This sounds like CDT, though, by conditioning on the past. If, for Newcomb’s problem, we condition on the past and so the contents of the boxes, we get that one-boxing was worse:
“Granted that the box that could have been empty was not empty, was it better to pick only that box?”. And the answer is no: you could have gotten more by two-boxing.
Of course, there’s something hidden here, which is that if the box that could have been empty was not empty, you could not have two-boxed (or with a weaker predictor, it’s unlikely that the box wasn’t empty and you would have two-boxed).
I think this is an interesting objection. E.g., “if you’re into EDT ex ante, shouldn’t you be into EDT ex post, and say that it was a ‘good action’ to learn about the Egyptians, because you learned that they were better off than you thought in expectation?” I think it depends, though, on how you are doing the ex post evaluation: and the objection doesn’t work if the ex post evaluation conditions on the information you learn.
That is, suppose that before you read Wikipedia, you were 50% on the Egyptians were at 0 welfare, and 50% they were at 10 welfare, so 5 in expectation, but reading is 0 EV. After reading, you find out that their welfare was 10. OK, should we count this action, in retrospect, as worth 5 welfare for the Egyptians? I’d say no, because the ex post evaluation should go: “Granted that the Egyptians were at 10 welfare, was it good to learn that they were at 10 welfare?”. And the answer is no: the learning was a 0-welfare change.
This sounds like CDT, though, by conditioning on the past. If, for Newcomb’s problem, we condition on the past and so the contents of the boxes, we get that one-boxing was worse:
Of course, there’s something hidden here, which is that if the box that could have been empty was not empty, you could not have two-boxed (or with a weaker predictor, it’s unlikely that the box wasn’t empty and you would have two-boxed).