Take the £10, and don’t bother opening the envelope. You are not (acausally) controlling whether £1′000′000 are in the envelope, but are controlling whether to take the £10, so you’ll take the £10 (since you are money-maximizing), and if Omega is correct, the envelope is going to be empty.
The agents that refuse the £10 in this situation will only be visited by Omega when the envelope contains the £1′000′000, while the money-maximizing agents will only be visited by Omega when the envelope is empty. By your decision, you don’t control whether the envelop contains money, but you do control whether Omega appears (since the statement asserted by Omega is about you). Thus, by deciding to take the money in this situation, you add expected £5 (or however often Omega appears) to your balance, by acausally summoning Omega.
By refusing the £10, you maximize the amount of money that the agents who see Omega get, by moving Omega around. It’s similar to trying to become a lottery winner by selling to existing lottery winners the same dietary supplement you take, since this makes the takers of this dietary supplement more likely to be lottery winners.
I haven’t worked through your formalization, but I do know that if I refuse, I get the £1000000! So I think something must be wrong with your implementation of the concept “money-maximizing”.
But you’re the one having the problem! :-) … I think. Omega, always right, says: “I predicted that you will refuse this £10 if and only if there is £1000 000 in Alpha’s envelope.” So refusing the £10 is my only chance at the £1000000, and I actually have the envelope where the £1000000 may be. Unless it spontaneously combusts, or someone snatches it away, the larger sum should be mine.
Your choice doesn’t change what’s inside the envelope. Not even a-causally. Your choice only affects whether or not Omega comes and offers you £10 or not, and you maximize your expected value there by being the kinda guy who takes £10 that’s offered. That way the 50% of time Alpha doesn’t send you £1 000 000, you get £10. Otherwise those 50% time you wouldn’t get anything.
But with Vladimir’s assumptions, he gets the £1000000 zero percent of the time! I quote:
the money-maximizing agents will only be visited by Omega when the envelope is empty
The description “money-maximizing” is wrong, but he is talking about a type of agent which does indeed make it impossible for Omega to ever show up while the £1000000 is there.
To return to your own comment,
our choice only affects whether or not Omega comes and offers you £10 or not,
correct
and you maximize your expected value there by being the kinda guy who takes £10 that’s offered.
You’re missing the fact that Alpha sending a letter happened regardless of Omega, and thus regardless of what you choose, you’d get £1 000 000 from Alpha 50% of time. You can’t choose so that you’d get £1 000 000 zero percent of the time simply because your choice doesn’t affect that.
I repeat that, since that seems to be the key problem here. Alpha flipped a coin to decide whether or not to send you £1 000 000. Your past or future actions don’t have any control over Alpha doing this, and sending you £1 000 000. In particular, your actions, upon receiving the envelope don’t have any, direct or indirect, entanglement with what does the envelope contain.
Your actions however are entangled with whether or not Omega comes along to offer you £10. If you’re the kinda guy to accept the £10, Omega makes this deal only when Alpha didn’t sent you £1 000 000. If you’re the kinda guy that refuses £10, Omega comes only when Alpha sent you £1 000 000.
So to maximize the expected value, you should accept the £10. That way, you get 50% time £1 000 000 and 50% £10. Otherwise you get 50% time £1 000 000 and 50% time £0
You can’t choose so that you’d get £1 000 000 zero percent of the time simply because your choice doesn’t affect that.
Vladimir (and you!) get £1000000 zero percent of the time on those occasions when Omega appears, and by hypothesis this is one of those occasions! You are committing a higher-order version of the two-box mistake.
Vladimir (and you!) get £1000000 zero percent of the time on those occasions when Omega appears
Exactly. Which is our purpose here. We want Omega to give £10 when we can accept it, not when we have to reject it. Which brings us back to my earlier statement:
So to maximize the expected value, you should accept the £10. That way, you get 50% time £1 000 000 and 50% £10. Otherwise you get 50% time £1 000 000 and 50% time £0
If you accept the £10, you get £10, and envelope will be empty. However, just as often(I’m assuming for simplicity that Omega appears always when possible) you receive envelope with £1 000 000 in it.
If you refuse £10, you find that the envelope holds £1 000 000. However, just as often you receive empty envelopes. Your expected value here is £500 000, whereas by accepting your expected value would be £500 005.
Your choice doesn’t affect what the envelope holds. It will just as often hold £1 000 000 and be empty. Only thing you can affect here is when does the Omega appear. This is very much unlike the Newcombs problem, where your choice actually affects what the boxes contain.
So effectively, only thing we do here is shift Omega-appearances to the times when we can accept the £10. Like I noted earlier, your choice has already caused Omega to appear, but it has not, and cannot, affect what the envelope contains.
Edit: I should clarify that Omega appearing is a double conditional, if you won, you won regardless. If you lost, you lost regardless. For Omega to appear, your choice, given Omega appearing, has to be the right kind, and result of Alpha coin toss has to be the right kind. If you’re the kinda guy to turn down the £10, for Omega to appear envelope has to contain the £1 000 000. Regardless of what you choose, you won anyway. This way however, if you didn’t win, Omega wouldn’t appear, offering you £10.
Like I noted earlier, your choice has already caused Omega to appear, but it has not, and cannot, affect what the envelope contains.
The nature of my decision procedure affects the conditions under which Omega can appear.
When I first confront this problem, I have not thought it through, but I know that Omega has appeared. So I ask: given that fact, what is the probability that the envelope contains the £1000000?
Without any knowledge of what my decision procedure is, the probability that the envelope contains the £1000000 is .5.
If I am a determined £10-taker, then the probability that the envelope contains the £1000000 is zero. If I am a determined £10-refuser, then the probability that the envelope contains the £1000000 is one.
But I am neither of those things. I am some more complicated decision-making system which is capable of either taking or refusing the £10, depending on which act is to my advantage. And I can see that if I refuse the £10, then there must be £1000000 in the envelope, which I get to keep. So, I refuse the £10.
Now it might be argued that I just got lucky. If I was as rational as you and Vladimir, then Omega would only ever appear when there was no money in the envelope. But because I hadn’t thought things through, it is possible for Omega to show up when there is money in the envelope, and in that case the right thing to do is what I did.
Basically, if you are already an entity which has reflectively optimized its decision procedure for Alpha-Omega situations, then you and Vladimir are making the right choice. But I was not such an entity, and so my choice was the right one for me.
Basically, if you are already an entity which has reflectively optimized its decision procedure for Alpha-Omega situations, then you and Vladimir are making the right choice. But I was not such an entity, and so my choice was the right one for me.
Actually, not. Like I said, your choice there doesn’t affect what the envelope contains. If you were rational like me and Vladimir, you wouldn’t meet Omega. You’d just receive an envelope with £1 000 000 in it. Funny thing with this envelope-puzzle is that Omega makes refursers and accepters to live in different conditionals. If you end up answering “refuse”, you’re in the conditional “Alpha decided to send you money”. If you answer “accept”, you’re in the conditional “Alpha decided not to send you money”. However, your choice doesn’t have any power over these conditionals, regardless of what you’d choose, Alpha’s coin toss wouldn’t be affected.
And because your choice doesn’t affect what the envelope contains, you’re not actually winning anything by refusing £10. Your refusal is simply a-causally making Omega appear in front of you after you got £1 000 000 from Alpha. Just like it is making a-causally Omega appear in front of me and Vladimir after we didn’t get anything. It doesn’t say anything about our chances to win £1 000 000, which were 50-50. And like I noted earlier, because of this, occasionally we receive enveloped that hold 1 000 000, while you occasionally receive empty envelopes.
If I am a determined £10-taker, then the probability that the envelope contains the £1000000 is zero. If I am a determined £10-refuser, then the probability that the envelope contains the £1000000 is one.
But I am neither of those things. I am some more complicated decision-making system which is capable of either taking or refusing the £10, depending on which act is to my advantage. And I can see that if I refuse the £10, then there must be £1000000 in the envelope, which I get to keep. So, I refuse the £10.
No. If you knowably refuse the £10 in this situation that makes you a determined £10-refuser. The fact that you personally did not know that you are a determined £10-refuser even though Omega did does not have any magical consequences.
Basically you can’t simultaneously take the fact that you have a choice and the fact that Omega is actually standing before you as given.
So Omega said, if you accept the ten pounds, I predict that Alpha gave you a bag of air. You accept the ten, and it turns out that Alpha still sends you ten million. So Omega is wrong. But Omega is never wrong. But he is. But he can’t be. But he is!
But he did. He’s in front of you. You’re the winner. And you’re going to tell him that you’d rather have ten pounds.
I understand that it’s more profitable to mop bathrooms in a public school than to buy lottery tickets, but if somebody tells you, “if you turn down this job, I will give you a winning ticket,” don’t go to work.
Omega only appears conditionally on at least the statement it asserts being correct. By taking/not taking its offer, you are only controlling the conditions under which Omega appears, and not contents of the envelope. By refusing the £10, you make sure that Omega appears only when the envelope is full (but you don’t make the envelope full, though it’s going to be full given that you’ve made this decision), and by accepting the £10, you make sure that Omega appears only when the envelope is empty.
It’s admittedly confusing that you can (acausally) control the conditions under which Omega appears (when the envelope is full/empty), when Omega remains right in front of you during the decision-making (this is analogous to controlling the contents of the big box in Newcomb’s problem) but at the same time, you don’t control the contents of the envelope.
By taking/not taking its offer, you are only controlling the conditions under which Omega appears
And by assuming you are a certain sort of agent (which you incorrectly call money-maximizing), you set those conditions to your own disadvantage! An agent which just flips a coin to decide whether to accept or refuse the £10 will have a bigger expected payoff than you. So surely a rational entity can do better.
And by assuming you are a certain sort of agent (which you incorrectly call money-maximizing), you set those conditions to your own disadvantage!
You are setting the conditions for appearance of Omega. The best conditions for Omega to appear are those where you take its money, since it’s good for nothing else.
By refusing the £10, you maximize the amount of money that the agents who see Omega get, by moving Omega around. It’s similar to trying to become a lottery winner by selling to existing lottery winners the same dietary supplement you take, since this makes the takers of this dietary supplement more likely to be lottery winners. (Added this paragraph to the top-level comment.)
I’m not 100% sure but it seems like you and Jonii are calculating correctly. It’s just ironic that if the situation as described happens to you, it means you were unlucky and there’s no money in Alpha’s envelope, whereas if it happens to someone like me, it means I was lucky and the £1000000 is there.
Not good. All you’ve achieved is redirected Omega to situations in which you don’t take its money. It’s better to have Omega where you do take its money, it’s free money.
For some reason, this reply specifically cemented the argument for me. Thank you—I now agree with you.
Edit: If it helps, my confusion was the appearance of causation from I-refuse-the-£10 to I-receive-the-£1e6. When you made this comment, I mentally went back and saw that the fraction of possible worlds in which Alpha gives me the million is unchanged by Omega’s prediction, and therefore that I can take the tenner without affecting it.
If there was a 50% chance Omega in the future visits someone who would refuse to take the £10 and gives them £1′000′000, and a 50% chance Omega visits someone who would accept the £10 and gives them £10 and an empty envelope, what would you prefer? Depending how you would behave if Omega visited you the probability of either the first or the second person being you is zero.
Would you still get the envelope if Omega wasn’t going to visit you? I had automatically assumed that Omega initiated the whole situation because the title said that Omega was subcontracting, but I see that the body doesn’t actually state that.
If that’s the scenario and if the only method Omega uses to ensure its prediction is accurate is selective visits your conclusion is obviously correct. I doubt there is anyone here who (correctly?) understood it that way and disagrees.
The main problem with such thought experiments is understanding them correctly (or better, having your formal decision theory represent them correctly), from where the conclusion usually follows trivially. Just try convincing a game theorist to cooperate in Prisoner’s dilemma, even experimental observations contradicting the theory of rational defection won’t help.
Take the £10, and don’t bother opening the envelope. You are not (acausally) controlling whether £1′000′000 are in the envelope, but are controlling whether to take the £10, so you’ll take the £10 (since you are money-maximizing), and if Omega is correct, the envelope is going to be empty.
The agents that refuse the £10 in this situation will only be visited by Omega when the envelope contains the £1′000′000, while the money-maximizing agents will only be visited by Omega when the envelope is empty. By your decision, you don’t control whether the envelop contains money, but you do control whether Omega appears (since the statement asserted by Omega is about you). Thus, by deciding to take the money in this situation, you add expected £5 (or however often Omega appears) to your balance, by acausally summoning Omega.
By refusing the £10, you maximize the amount of money that the agents who see Omega get, by moving Omega around. It’s similar to trying to become a lottery winner by selling to existing lottery winners the same dietary supplement you take, since this makes the takers of this dietary supplement more likely to be lottery winners.
I give formalization of this solution in another comment.
Huh? Omega is there and says that if and only if you refuse will there be £1000 000 in the envelope. Aren’t you turning down £1000 000 for £10?
Nope. I find my explanation pretty clear, can you point to what in particular you don’t follow?
I haven’t worked through your formalization, but I do know that if I refuse, I get the £1000000! So I think something must be wrong with your implementation of the concept “money-maximizing”.
This doesn’t clarify the problem you are having.
But you’re the one having the problem! :-) … I think. Omega, always right, says: “I predicted that you will refuse this £10 if and only if there is £1000 000 in Alpha’s envelope.” So refusing the £10 is my only chance at the £1000000, and I actually have the envelope where the £1000000 may be. Unless it spontaneously combusts, or someone snatches it away, the larger sum should be mine.
Your choice doesn’t change what’s inside the envelope. Not even a-causally. Your choice only affects whether or not Omega comes and offers you £10 or not, and you maximize your expected value there by being the kinda guy who takes £10 that’s offered. That way the 50% of time Alpha doesn’t send you £1 000 000, you get £10. Otherwise those 50% time you wouldn’t get anything.
But with Vladimir’s assumptions, he gets the £1000000 zero percent of the time! I quote:
The description “money-maximizing” is wrong, but he is talking about a type of agent which does indeed make it impossible for Omega to ever show up while the £1000000 is there.
To return to your own comment,
correct
wrong!
You’re missing the fact that Alpha sending a letter happened regardless of Omega, and thus regardless of what you choose, you’d get £1 000 000 from Alpha 50% of time. You can’t choose so that you’d get £1 000 000 zero percent of the time simply because your choice doesn’t affect that.
I repeat that, since that seems to be the key problem here. Alpha flipped a coin to decide whether or not to send you £1 000 000. Your past or future actions don’t have any control over Alpha doing this, and sending you £1 000 000. In particular, your actions, upon receiving the envelope don’t have any, direct or indirect, entanglement with what does the envelope contain.
Your actions however are entangled with whether or not Omega comes along to offer you £10. If you’re the kinda guy to accept the £10, Omega makes this deal only when Alpha didn’t sent you £1 000 000. If you’re the kinda guy that refuses £10, Omega comes only when Alpha sent you £1 000 000.
So to maximize the expected value, you should accept the £10. That way, you get 50% time £1 000 000 and 50% £10. Otherwise you get 50% time £1 000 000 and 50% time £0
Vladimir (and you!) get £1000000 zero percent of the time on those occasions when Omega appears, and by hypothesis this is one of those occasions! You are committing a higher-order version of the two-box mistake.
Exactly. Which is our purpose here. We want Omega to give £10 when we can accept it, not when we have to reject it. Which brings us back to my earlier statement:
If you accept the £10, you get £10, and envelope will be empty. However, just as often(I’m assuming for simplicity that Omega appears always when possible) you receive envelope with £1 000 000 in it.
If you refuse £10, you find that the envelope holds £1 000 000. However, just as often you receive empty envelopes. Your expected value here is £500 000, whereas by accepting your expected value would be £500 005.
Your choice doesn’t affect what the envelope holds. It will just as often hold £1 000 000 and be empty. Only thing you can affect here is when does the Omega appear. This is very much unlike the Newcombs problem, where your choice actually affects what the boxes contain.
So effectively, only thing we do here is shift Omega-appearances to the times when we can accept the £10. Like I noted earlier, your choice has already caused Omega to appear, but it has not, and cannot, affect what the envelope contains.
Edit: I should clarify that Omega appearing is a double conditional, if you won, you won regardless. If you lost, you lost regardless. For Omega to appear, your choice, given Omega appearing, has to be the right kind, and result of Alpha coin toss has to be the right kind. If you’re the kinda guy to turn down the £10, for Omega to appear envelope has to contain the £1 000 000. Regardless of what you choose, you won anyway. This way however, if you didn’t win, Omega wouldn’t appear, offering you £10.
The nature of my decision procedure affects the conditions under which Omega can appear.
When I first confront this problem, I have not thought it through, but I know that Omega has appeared. So I ask: given that fact, what is the probability that the envelope contains the £1000000?
Without any knowledge of what my decision procedure is, the probability that the envelope contains the £1000000 is .5.
If I am a determined £10-taker, then the probability that the envelope contains the £1000000 is zero. If I am a determined £10-refuser, then the probability that the envelope contains the £1000000 is one.
But I am neither of those things. I am some more complicated decision-making system which is capable of either taking or refusing the £10, depending on which act is to my advantage. And I can see that if I refuse the £10, then there must be £1000000 in the envelope, which I get to keep. So, I refuse the £10.
Now it might be argued that I just got lucky. If I was as rational as you and Vladimir, then Omega would only ever appear when there was no money in the envelope. But because I hadn’t thought things through, it is possible for Omega to show up when there is money in the envelope, and in that case the right thing to do is what I did.
Basically, if you are already an entity which has reflectively optimized its decision procedure for Alpha-Omega situations, then you and Vladimir are making the right choice. But I was not such an entity, and so my choice was the right one for me.
Actually, not. Like I said, your choice there doesn’t affect what the envelope contains. If you were rational like me and Vladimir, you wouldn’t meet Omega. You’d just receive an envelope with £1 000 000 in it. Funny thing with this envelope-puzzle is that Omega makes refursers and accepters to live in different conditionals. If you end up answering “refuse”, you’re in the conditional “Alpha decided to send you money”. If you answer “accept”, you’re in the conditional “Alpha decided not to send you money”. However, your choice doesn’t have any power over these conditionals, regardless of what you’d choose, Alpha’s coin toss wouldn’t be affected.
And because your choice doesn’t affect what the envelope contains, you’re not actually winning anything by refusing £10. Your refusal is simply a-causally making Omega appear in front of you after you got £1 000 000 from Alpha. Just like it is making a-causally Omega appear in front of me and Vladimir after we didn’t get anything. It doesn’t say anything about our chances to win £1 000 000, which were 50-50. And like I noted earlier, because of this, occasionally we receive enveloped that hold 1 000 000, while you occasionally receive empty envelopes.
No. If you knowably refuse the £10 in this situation that makes you a determined £10-refuser. The fact that you personally did not know that you are a determined £10-refuser even though Omega did does not have any magical consequences.
Basically you can’t simultaneously take the fact that you have a choice and the fact that Omega is actually standing before you as given.
Apparently someone thinks there is something wrong with this. Could they please explain?
Click.
Thanks!
So Omega said, if you accept the ten pounds, I predict that Alpha gave you a bag of air. You accept the ten, and it turns out that Alpha still sends you ten million. So Omega is wrong. But Omega is never wrong. But he is. But he can’t be. But he is!
No.
If Alpha sends you 10m and you would accept the ten, Omega doesn’t make the stated prediction.
But he did. He’s in front of you. You’re the winner. And you’re going to tell him that you’d rather have ten pounds.
I understand that it’s more profitable to mop bathrooms in a public school than to buy lottery tickets, but if somebody tells you, “if you turn down this job, I will give you a winning ticket,” don’t go to work.
Omega only appears conditionally on at least the statement it asserts being correct. By taking/not taking its offer, you are only controlling the conditions under which Omega appears, and not contents of the envelope. By refusing the £10, you make sure that Omega appears only when the envelope is full (but you don’t make the envelope full, though it’s going to be full given that you’ve made this decision), and by accepting the £10, you make sure that Omega appears only when the envelope is empty.
It’s admittedly confusing that you can (acausally) control the conditions under which Omega appears (when the envelope is full/empty), when Omega remains right in front of you during the decision-making (this is analogous to controlling the contents of the big box in Newcomb’s problem) but at the same time, you don’t control the contents of the envelope.
And by assuming you are a certain sort of agent (which you incorrectly call money-maximizing), you set those conditions to your own disadvantage! An agent which just flips a coin to decide whether to accept or refuse the £10 will have a bigger expected payoff than you. So surely a rational entity can do better.
You are setting the conditions for appearance of Omega. The best conditions for Omega to appear are those where you take its money, since it’s good for nothing else.
By refusing the £10, you maximize the amount of money that the agents who see Omega get, by moving Omega around. It’s similar to trying to become a lottery winner by selling to existing lottery winners the same dietary supplement you take, since this makes the takers of this dietary supplement more likely to be lottery winners.
(Added this paragraph to the top-level comment.)
I’m not 100% sure but it seems like you and Jonii are calculating correctly. It’s just ironic that if the situation as described happens to you, it means you were unlucky and there’s no money in Alpha’s envelope, whereas if it happens to someone like me, it means I was lucky and the £1000000 is there.
So you refuse the £10?
No, I don’t. Why?
I’m sorry—I was confused when I wrote that comment.
Re: “The agents that refuse the £10 in this situation will only be visited by Omega when the envelope contains the £1′000′000”
That sounds good to me!
Not good. All you’ve achieved is redirected Omega to situations in which you don’t take its money. It’s better to have Omega where you do take its money, it’s free money.
For some reason, this reply specifically cemented the argument for me. Thank you—I now agree with you.
Edit: If it helps, my confusion was the appearance of causation from I-refuse-the-£10 to I-receive-the-£1e6. When you made this comment, I mentally went back and saw that the fraction of possible worlds in which Alpha gives me the million is unchanged by Omega’s prediction, and therefore that I can take the tenner without affecting it.
Right—and finally I am there as well :-)
If there was a 50% chance Omega in the future visits someone who would refuse to take the £10 and gives them £1′000′000, and a 50% chance Omega visits someone who would accept the £10 and gives them £10 and an empty envelope, what would you prefer? Depending how you would behave if Omega visited you the probability of either the first or the second person being you is zero.
Refuse obviously. You’ve described how my choice controls the payoff, which is not the case with Alpha.
Would you still get the envelope if Omega wasn’t going to visit you? I had automatically assumed that Omega initiated the whole situation because the title said that Omega was subcontracting, but I see that the body doesn’t actually state that.
Edited to make this clear
Yes, this seems to be assumed, though it didn’t actually happen this way, Omega did visit you.
If that’s the scenario and if the only method Omega uses to ensure its prediction is accurate is selective visits your conclusion is obviously correct. I doubt there is anyone here who (correctly?) understood it that way and disagrees.
The main problem with such thought experiments is understanding them correctly (or better, having your formal decision theory represent them correctly), from where the conclusion usually follows trivially. Just try convincing a game theorist to cooperate in Prisoner’s dilemma, even experimental observations contradicting the theory of rational defection won’t help.