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Quantum Decisions

1 Post author: Alexei 12 May 2014 09:49PM

CFAR sometimes plays a Monday / Tuesday game (invented by palladias). Copying from the URL:

On Monday, your proposition is true. On Tuesday, your proposition is false. Tell me a story about each of the days so I can see how they are different. Don't just list the differences (because you're already not doing that well). Start with "I wake up" so you start concrete and move on in that vein, naming the parts of your day that are identical as well as those that are different.

So my question is (edited on 2014/05/13):

On Monday, I make my decisions by rolling a normal die. Example: should I eat vanilla or chocolate ice-cream? I then decide that if I roll 4 or higher on a 6-sided die, I'll pick vanilla. I roll the die, get a 3, and so proceed to eat chocolate ice-cream.

On Tuesday, I use the same procedure, but use a quantum random number generator instead. (For the purpose of this discussion, let's assume that I can actually find a true/reliable generator. May be I'm shooting a photon through a half-silvered mirror.)

What's the difference? (Relevant discussion pointed out Pfft.)

Comments (20)

Comment author: Pfft 13 May 2014 05:11:50PM 4 points [-]

I guess part of what you are asking about is the difference between using a quantum random number source, and using a deterministic pseudorandom number source (which happens to be inside your brain). Stuart Armstrong wrote Quantum versus Logical Bombs about one difference, suggesting that maybe risk-averse actors should prefer the quantum version (because then even if you make a bad decision, at least there will exist some multiple worlds in which you didn't...).

Comment author: Alexei 13 May 2014 05:55:19PM 0 points [-]

Yes! Thank you, Pfft, that's exactly what I was trying to get at. I'll go read the post right now.

Comment author: DanielLC 12 May 2014 11:34:09PM 2 points [-]

People are underconfident when predicting their own decisions. As a result, I would expect that you will be more likely to go with the highest probability decision on Monday than Tuesday. I suspect it will tend to be the better decision.

Comment author: gjm 12 May 2014 10:15:47PM 4 points [-]

One obvious difference (which you may or may not have intended) is that on Tuesday, all your decisions need to be made consciously and with some explicit calculation. This makes the decision-making process more cumbersome, and also means you engage different bits of mental machinery from Monday, which will lead to decisions that differ in various ways.

I gravely doubt whether the Tuesday scenario is actually anything remotely like possible, but that may not matter.

All the above would be just the same if you were just rolling dice. Is the real point of the question something to do with the quantumness of the random number generator? If so, I think you need to be more explicit about what sort of difference you think there might be (or think that others think there might be).

Comment author: DanielLC 12 May 2014 11:32:42PM 2 points [-]

Hardware random number generators often use quantum effects for randomness. Though I agree that specifying quantum is pointless.

Comment author: Alexei 13 May 2014 01:02:52AM 0 points [-]

Yeah, that's not what I was getting at.

Not for every single decision, but let's say for 10 / day.

Yes, the quantumness is the point. Let's say I'm shooting photons through a half-silvered mirror or something like that.

By the way, "there is no difference" is a perfectly acceptable answer, if it's true.

Comment author: gjm 13 May 2014 08:18:41PM 1 point [-]

I would be astonished if it made any difference. Not least because I bet your decisions already are well enough quantum-randomized: the universe is a quantum system, after all, and while maybe most everyday things can be adequately described as <something non-quantum> plus small errors, those small errors often grow exponentially over time.

Comment author: shminux 12 May 2014 10:24:38PM 1 point [-]

Why are you using the word "quantum" here? Do you expect any difference if you use a classical pseudo-random number generator... say, on Wednesday?

Comment author: Alexei 13 May 2014 01:35:39AM 0 points [-]

May be. That's the point of this question.

Comment author: shminux 13 May 2014 04:56:10PM -2 points [-]

That's the point of this question.

I don't think it is the point at all, since the difference between quantum random and pseudorandom has nothing to do with making decisions. I think you are simply using a cool-sounding word "quantum" where "probabilistic" is what you really mean.

Comment author: Alexei 13 May 2014 05:51:31PM 0 points [-]

Sigh. No, I mean precisely quantum and not probabilistic. I'm wondering how it affects the "reality fluid", for example. I'll go and edit the question to make it more clear.

Comment author: shminux 13 May 2014 06:55:32PM 0 points [-]

Ah, so you are taking the MWI ontology as if it were something testable. Gotcha. Let me just note that if your logic relies on untestables, it's not a good one. If the visible outcome changes when you replace "Everett branches" with "possible worlds", you are doing something wrong.

I'm wondering how it affects the "reality fluid", for example.

"Reality fluid" is EYspeak for "I have no clue", and he stated as much, though not in quite that way. It's not a good term, as it gives a false impression of explaining/modeling something. Don't use it.

Comment author: Pfft 15 May 2014 01:59:44AM *  0 points [-]

The idea of the term is exactly to draw attention to the fact that it doesn't explain or model anything (by analogy with Phlogiston).

Comment author: shminux 15 May 2014 05:43:19AM 0 points [-]

I don't think we disagree.

Comment author: Nisan 13 May 2014 02:04:03PM 1 point [-]

On Monday, I have to decide whether to eat ice cream or not. After a little thought, I decide it's all right to eat ice cream because <reason>. The reason is a lame reason that my mind came up with because it really wants ice cream.

On Tuesday I only eat ice cream with 50% probability.

Comment author: Alexei 13 May 2014 06:26:51PM 0 points [-]

Nisan, please see the revised version of the question.

On Tuesday, I'm still picking my threshold "manually". Let's say the quantum random number generator I use can give me a random 1-6 number, just like a 6-sided die, so I'm not stuck with 50/50.

Comment author: Dorikka 13 May 2014 12:15:04AM 1 point [-]

By Wednesday you're convinced that infinitely recursive strategies may not be as awesome as they originally seemed.

Comment author: V_V 12 May 2014 10:41:07PM 1 point [-]

So on Tuesday you use mixed strategies, and on Monday you use...?

Comment author: ESRogs 13 May 2014 12:05:13AM *  0 points [-]

Two questions:

  1. What kind of decisions do you have in mind? Presumably I'm not rolling each time I take a step (or not) while walking down the street, right?

  2. Is there any reason not to say 100% for all my decisions on Tuesday? (Assuming I don't happen to find myself in any adversarial interactions with Omega.)

Comment author: Alexei 13 May 2014 01:04:08AM 1 point [-]
  1. See my answer to gjm.

  2. Let's say I'm lazy, and I can't decide for sure if I want vanilla or chocolate. Rolling the quantum die seems easier.