Agent X is a piece of paper with “Defect” written on it.
Sorry, was this intended as part of the problem statement, like “Omega tells you that agent X is a DefectBot that will play the same as you”? If yes, then ok. But if we don’t know what agent X is, then I don’t understand why a DefectBot is apriori more probable than a CooperateBot. If they are equally probable, then it cancels out (edit: no it doesn’t, it actually makes cooperating a better choice, thx ArisKatsaris). And there’s also the case where X is a copy of you, where cooperating does help. So it seems to be a better choice overall.
Sorry, was this intended as part of the problem statement, like “Omega tells you that agent X is a DefectBot that will play the same as you”? If yes, then ok. But if we don’t know what agent X is, then I don’t understand why a DefectBot is apriori more probable than a CooperateBot. If they are equally probable, then it cancels out (edit: no it doesn’t, it actually makes cooperating a better choice, thx ArisKatsaris). And there’s also the case where X is a copy of you, where cooperating does help. So it seems to be a better choice overall.
There is also a case where X is an anticopy (performs opposite action), which argues for defecting in the same manner.
Edit: This reply is wrong.
No it doesn’t. If X is an anticopy, the situation can’t be real and your action doesn’t matter.
Why can’t it be real?
Because Omega has told you that X’s action is the same as yours.
OK.