There are a couple of things I find odd about this. First, it seems to be taken for granted that one-boxing is obviously better than two boxing, but I'm not sure that's right. J.M. Joyce has an argument (in his foundations of causal decision theory) that is supposed to convince you that two-boxing is the right solution. Importantly, he accepts that you might still wish you weren't a CDT (so that Omega predicted you would one-box). But, he says, in either case, once the boxes are in front of you, whether you are a CDT or a EDT, you should two-box! The dominance reasoning works in either case, once the prediction has been made and the boxes are in front of you.

But this leads me on to my second point. I'm not sure how much of a flaw Newcomb's problem is in a decision theory, given that it relies on the intervention of an alien that can accurately predict what you will do. Let's leave aside the general problem of predicting real agents' actions with that degree of accuracy. If you know that the prediction of your choice affects the success of your choices, I think that reflexivity or self reference simply makes the prediction meaningless. We're all used to self-reference being tricky, and I think in this case it just undermines the whole set up. That is, I don't see the force of the objection from Newcomb's problem, because I don't think it's a problem we could ever possibly face.

Here's an example of a related kind of "reflexivity makes prediction meaningless". Let's say Omega bets you $100 that she can predict what you will eat for breakfast. Once you accept this bet, you now try to think of something that you would never otherwise think to eat for breakfast, in order to win the bet. The fact that your actions and the prediction of your actions have been connected in this way by the bet makes your actions unpredictable.

Going on to the prisoner's dilemma. Again, I don't think that it's the job of decision theory to get "the right" result in PD. Again, the dominance reasoning seems impeccable to me. In fact, I'm tempted to say that I would want any future advanced decision theory to satisfy some form of this dominance principle: it's crazy to ever choice an act that is guaranteed to be worse. All you need to do to "fix" PD is to have the agent attach enough weight to the welfare of others. That's not a modification of the decision theory, that's a modification of the utility function.

As I understand what is meant by satisficing, this misses the mark. A satisficer will search for an action until it finds one that is good enough, then it will do that. A maximiser will search for the best action and then do that. A bounded maximser will search for the "best" (best according to its bounded utility function) and then do that.

So what the satisficer picks depends on what order the possible actions are presented to it in a way it doesn't for either maximiser. Now, if easier options are presented to it first then I guess your conclusion still follows, as long as we grant the premise that self-transforming will be easy.

But I don't think it's right to identify bounded maximisers and satisficers.

Any logically coherent body of doctrine is sure to be in part painful and contrary to current prejudices

– Bertrand Russell, History of Western Philosophy p. 98

Bertie is a goldmine of rationality quotes.

Agreed, the structural component is not normative. But to me, it is the structural part that seems benign.

If we assume the agent lives forever, and there's always some uncertainty, then surely the world is thus and so. If the agent doesn't live forever, then we're into bounded rationality questions, and even transitivity is up in the air.

The greatest challenge to any thinker is stating the problem, in a way that will allow a solution

– Bertrand Russell

Anyone who can handle a needle convincingly can make us see a thread which isn't there

-E.H. Gombrich

Suppose that I wanted to demonstrate conclusively that a generalization was false. I would have to provide one or more counterexamples. What sort of thing would be a counterexample to the claim "each party to all disputes that persist through long periods of time is partly right and partly wrong?" Well, it would have to be a dispute that persisted through long periods of time, but in which there was a party that was not partly right and partly wrong.

So in my above reply, I listed some disputes that persisted for long periods of time, but in which there was (or is) a party that was not partly right and partly wrong.

P6 is really both. Structurally, it forces there to be something like a coin that we can flip as many times as we want. But normatively, we can say that if the agent has blah blah blah preference, it shall be able to name a partition such that blah blah blah. See e.g. [rule 4]. This of course doesn't address why we think such a thing is normative, but that's another issue.

Right. So calling it a "false generalization" needed two words.

Anyhow: Where does the sun go at night? How big is the earth? Is it harmful to market cigarettes to teenagers? Is Fermat's last theorem true? Can you square the circle? Will heathens burn in hell for all eternity?

This thought isn't original to me, but it's probably worth making. It feels like there are two sorts of axioms. I am following tradition in describing them as "rationality axioms" and "structure axioms". The rationality axioms (like the transitivity of the order among acts) are norms on action. The structure axioms (like P6) aren't normative at all. (It's about structure on the world, how bizarre is it to say "The world ought to be such that P6 holds of it"?)

Given this, and given the necessity of the structure axioms for the proof, it feels like Savage's theorem can't serve as a justification of Bayesian epistemolgy as a norm of rational behaviour.