Sort of a side note to the main topic of discussion but being as my post was quoted, maybe worth responding:
The great thing about comparing an argument to one in the philosophical literature is that it provides access to a whole range of papers on the issue so that ideas don't need to be rediscovered. The corresponding bad thing though is it makes it easy to accidentally commit a straw man attack if the argument isn't actually the same as the one in the literature. So I'll outline my argument (basically I'll extend on the quote of mine you used).
If we think of rationality as utility maximisation then two boxing on Newcomb's Problem seems rational due to the principle of strong dominance which basically argues that, whatever state the boxes are in, you benefit from two boxing.
But if the priniciple of strong dominance is itself an irrational way of making decisions then a decision made according to this principle is no longer a rational way of behaving. My argument is basically that Newcombe's Problem shows that strong dominance is an irrational way to make decisions because you do not in fact benefit regardless of circumstances by following strong dominance.
If your decision procedure is irrational then decisions made due to that procedure are no longer rational.
That's not the same as saying irrational people never win. As you note, if you build irrationality into the scenario, then whatever definition of rationality you have, you can be made to lose. Nevertheless, that doesn't change my argument that one boxing on Newcomb's is rational (even if you think it is irrational, this particular attack doesn't seem relevant to my argument).
I'm not looking for a decision theory that "wins" in every possible circumstance. I am, however, looking for one that wins in more circumstances than EDT and CDT do.
Hi Adam, can I ask for a little more clarification here? You write:
My argument is basically that Newcombe's Problem shows that strong dominance is an irrational way to make decisions because you do not in fact benefit regardless of circumstances by following strong dominance
Newcomb's Problem is a case where Omega punishes those who are disposed to follow strong dominance reasoning. But how, exactly, does it follow from this that dominance reasoning isn't rational? It may just be a case where Omega punishes those who are disposed to reason rationally. (If dominance reasoning is indeed rational, then this is the right way to describe the case.)
A common background assumption on LW seems to be that it's rational to act in accordance with the dispositions one would wish to have. (Rationalists must WIN, and all that.)
E.g., Eliezer:
And more recently, from AdamBell:
Within academic philosophy, this is the position advocated by David Gauthier. Derek Parfit has constructed some compelling counterarguments against Gauthier, so I thought I'd share them here to see what the rest of you think.
First, let's note that there definitely are possible cases where it would be "beneficial to be irrational". For example, suppose an evil demon ('Omega') will scan your brain, assess your rational capacities, and torture you iff you surpass some minimal baseline of rationality. In that case, it would very much be in your interests to fall below the baseline! Or suppose you're rewarded every time you honestly believe the conclusion of some fallacious reasoning. We can easily multiply cases here. What's important for now is just to acknowledge this phenomenon of 'beneficial irrationality' as a genuine possibility.
This possibility poses a problem for the Eliezer-Gauthier methodology. (Quoting Eliezer again:)
The problem, obviously, is that it's possible for irrational agents to receive externally-generated rewards for their dispositions, without this necessarily making their downstream actions any more 'reasonable'. (At this point, you should notice the conflation of 'disposition' and 'choice' in the first quote from Eliezer. Rachel does not envy Irene her choice at all. What she wishes is to have the one-boxer's dispositions, so that the predictor puts a million in the first box, and then to confound all expectations by unpredictably choosing both boxes and reaping the most riches possible.)
To illustrate, consider (a variation on) Parfit's story of the threat-fulfiller and threat-ignorer. Tom has a transparent disposition to fulfill his threats, no matter the cost to himself. So he straps on a bomb, walks up to his neighbour Joe, and threatens to blow them both up unless Joe shines his shoes. Seeing that Tom means business, Joe sensibly gets to work. Not wanting to repeat the experience, Joe later goes and pops a pill to acquire a transparent disposition to ignore threats, no matter the cost to himself. The next day, Tom sees that Joe is now a threat-ignorer, and so leaves him alone.
So far, so good. It seems this threat-ignoring disposition was a great one for Joe to acquire. Until one day... Tom slips up. Due to an unexpected mental glitch, he threatens Joe again. Joe follows his disposition and ignores the threat. BOOM.
Here Joe's final decision seems as disastrously foolish as Tom's slip up. It was good to have the disposition to ignore threats, but that doesn't necessarily make it good idea to act on it. We need to distinguish the desirability of a disposition to X from the rationality of choosing to do X.