Follow-up to: Normative uncertainty in Newcomb's problem
Philosophers and atheists break for two-boxing; theists and Less Wrong break for one-boxing
Personally, I would one-box on Newcomb's Problem. Conditional on one-boxing for lawful reasons, one boxing earns $1,000,000, while two-boxing, conditional on two-boxing for lawful reasons, would deliver only a thousand. But this seems to be firmly a minority view in philosophy, and numerous heuristics about expert opinion suggest that I should re-examine the view.
In the PhilPapers survey, Philosophy undergraduates start off divided roughly evenly between one-boxing and two-boxing:
Newcomb's problem: one box or two boxes?
| Other | 142 / 217 (65.4%) |
| Accept or lean toward: one box | 40 / 217 (18.4%) |
| Accept or lean toward: two boxes | 35 / 217 (16.1%) |
But philosophy faculty, who have learned more (less likely to have no opinion), and been subject to further selection, break in favor of two-boxing:
Newcomb's problem: one box or two boxes?
| Other | 441 / 931 (47.4%) |
| Accept or lean toward: two boxes | 292 / 931 (31.4%) |
| Accept or lean toward: one box | 198 / 931 (21.3%) |
Specialists in decision theory (who are also more atheistic, more compatibilist about free will, and more physicalist than faculty in general) are even more convinced:
Newcomb's problem: one box or two boxes?
| Accept or lean toward: two boxes | 19 / 31 (61.3%) |
| Accept or lean toward: one box | 8 / 31 (25.8%) |
| Other | 4 / 31 (12.9%) |
Looking at the correlates of answers about Newcomb's problem, two-boxers are more likely to believe in physicalism about consciousness, atheism about religion, and other positions generally popular around here (which are also usually, but not always, in the direction of philosophical opinion). Zooming in one correlate, most theists with an opinion are one-boxers, while atheists break for two-boxing:
| Newcomb's problem:two boxes | 0.125 | |||||||||||||||||
Response pairs: 655 p-value: 0.001
|
||||||||||||||||||
Less Wrong breaks overwhelmingly for one-boxing in survey answers for 2012:
NEWCOMB'S PROBLEM
One-box: 726, 61.4%
Two-box: 78, 6.6%
Not sure: 53, 4.5%
Don't understand: 86, 7.3%
No answer: 240, 20.3%
When I elicited LW confidence levels in a poll, a majority indicated 99%+ confidence in one-boxing, and 77% of respondents indicated 80%+ confidence.
What's going on?
I would like to understand what is driving this difference of opinion. My poll was a (weak) test of the hypothesis that Less Wrongers were more likely to account for uncertainty about decision theory: since on the standard Newcomb's problem one-boxers get $1,000,000, while two-boxers get $1,000, even a modest credence in the correct theory recommending one-boxing could justify the action of one-boxing.
If new graduate students read the computer science literature on program equilibrium, including some local contributions like Robust Cooperation in the Prisoner's Dilemma and A Comparison of Decision Algorithms on Newcomblike Problems, I would guess they would tend to shift more towards one-boxing. Thinking about what sort of decision algorithms it is rational to program, or what decision algorithms would prosper over numerous one-shot Prisoner's Dilemmas with visible source code, could also shift intuitions. A number of philosophers I have spoken with have indicated that frameworks like the use of causal models with nodes for logical uncertainty are meaningful contributions to thinking about decision theory. However, I doubt that for those with opinions, the balance would swing from almost 3:1 for two-boxing to 9:1 for one-boxing, even concentrating on new decision theory graduate students.
On the other hand, there may be an effect of unbalanced presentation to non-experts. Less Wrong is on average less philosophically sophisticated than professional philosophers. Since philosophical training is associated with a shift towards two-boxing, some of the difference in opinion could reflect a difference in training. Then, postings on decision theory have almost all either argued for or assumed one-boxing as the correct response on Newcomb's problem. It might be that if academic decision theorists were making arguments for two-boxing here, or if there was a reduction in pro one-boxing social pressure, there would be a shift in Less Wrong opinion towards two-boxing.
Less Wrongers, what's going on here? What are the relative causal roles of these and other factors in this divergence?
ETA: The SEP article on Causal Decision Theory.
Yes. Which is to say, clearly you fall into the second class of people (those who have studied decision theory a lot) and hence my explanation was not meant to apply to you.
Which isn't to say I agree with everything you say.
Decisions can have different causal impacts to decision theories and so there seems to be no reason to accept this claim. Insofar as the rational decision is the decision which wins which depends on the causal effects of the decision and the rational algorithm is the algorithm which wins which depends on the causal effects of the algorithm then there seems to be no reason to think these should coincide. Plus, I like being able to draw distinctions that can't be drawn using your terminology.
Agreed (if you are faced with a decision of which algorithm to follow). Of course, this is not the decision that you're faced with in NP (and adding more options is just to deny the hypothetical)
Yes, and I think this is an impressive achievement and I find TDT/UDT to be elegant, useful theories. The fact that I make the distinction between rational theories and rational decisions does not mean I cannot value the answers to both questions.
Well...perhaps. Obviously just because you can maximise over algorithms, it doesn't follow that you can't still talk about maximising over causal consequences. So either we have a (boring) semantic debate about what we mean by "decisions" or a debate about practicality: that is, the argument would be that talk about maximising over algorithms is clearly more useful than talk about maximising over causal consequences so why care about the second of these. For the most part, I buy this argument about practicality (but it doesn't mean that two-boxing philosophers are wrong, just that they're playing a game that both you and I feel little concern for).
I know what all these phrases mean but don't know why it follows that your theory is not maximising the "right" thing. Perhaps it is not maximising a thing that you find to be useful or interesting (particularly for self-modifying AIs). If this is what you mean then fine. If you mean, however, that two-boxers are wrong on their own terms then I would need a more compelling argument (I've read your TDT paper btw, so reference to that won't resolve things here).
Sure, the distinction is from the CDT perspective. You use words differently to the proponents of CDT (at which point, the whole difference between LWer views and philosopher's views should be unsurprising). I'm not really interested in getting into a semantic debate though. I think that LWers are too quick to think that philosophers are playing the game wrong whereas I think the view should actually be that they're playing the wrong game.
No, my point is that TDT, as a theory, maximizes over a space of decisions, not a space of... (read more)