Section 3.3.3 says that a selfish agent should make the same decisions as an average-utilitarian who averages over just the set of people who may be “me”, right? That’s why it says that in the incubator experiment, a selfish agent who has been told she is in Room 1 should pay 1⁄2 for the ticket. An average-utilitarian who averages over everyone who exists in a world would pay 2⁄3 instead.
So in my example, consider an average-utilitarian whose attention is restricted to just people who have heard “heads”. Then buying a ticket loses an average of x in the tails world, and gains an average of 1-x in the heads world, so such an restricted-average-utilitarian would pay x<1/2.
(If this is still not making sense, please contact me on Google Chat where we can probably hash it out much more quickly.)
We’ll talk on google chat. But my preliminary thought is that if you are indeed restricting to those who have heard heads, then you need to make use of the fact that this objectively much more likely to happen in the heads world than in the tails.
Section 3.3.3 says that a selfish agent should make the same decisions as an average-utilitarian who averages over just the set of people who may be “me”, right? That’s why it says that in the incubator experiment, a selfish agent who has been told she is in Room 1 should pay 1⁄2 for the ticket. An average-utilitarian who averages over everyone who exists in a world would pay 2⁄3 instead.
So in my example, consider an average-utilitarian whose attention is restricted to just people who have heard “heads”. Then buying a ticket loses an average of x in the tails world, and gains an average of 1-x in the heads world, so such an restricted-average-utilitarian would pay x<1/2.
(If this is still not making sense, please contact me on Google Chat where we can probably hash it out much more quickly.)
We’ll talk on google chat. But my preliminary thought is that if you are indeed restricting to those who have heard heads, then you need to make use of the fact that this objectively much more likely to happen in the heads world than in the tails.