Dreams with Damaged Priors

I've heard it said somewhere (sorry, can't come up with a citation) that this is the rationale behind the brain's tendency to actively erase dreams, the bane of dream-diary keepers everywhere. Because we're somewhat source-blind, we risk keeping our attachment to conclusions we made in dreams even after we realize we were dreaming. To prevent that, the brain erases most of the five or so dreams we have each night, and even the ones we remember on waking tend to be mostly erased in a few hours unless you consciously think about them very hard.

Rationality in dreams, fun topic...

Since early adolescence, I've experienced episodes of "sleep paralysis" just before waking a few times per month. The experience is different for each individual, but most people dream/hallucinate waking up, but being unable to move at least one part of their body. It can be very disturbing, especially if you can see all the normal things associated with waking up (like your alarm clock on the nightstand, your spouse next to you/talking to you, etc.).

When it first started happening to me regularly, each occurrence really freaked me out. I'd hallucinate waking up to storm winds breaking out my windows, but being unable to move, or being awake and trying to get up, but having my vision frozen in one spot. I would wake up sweating, breathing heavily, and very disturbed.

After several years, I've developed a sort of dream rationality, in which I "wake up" and experience some sort of paralysis (a lot of times I dream that my neck is forced into some terrible position), and then consider how likely the scenario is to being not-real before I get upset. I recall recently "waking up" to a burglar going through my closet, and I being unable to move anything but my eyelids. I started to get a little excited, but then I considered "How likely is it that a burglar silently defeated my deadbolt AND I spontaneously became paralyzed?" I considered this conjunction to be exceedingly improbable, so I sat back and let the scene play out, and a minute (probably not really) or so later I woke up for real.

If only I could apply this type of reasoning to dreams about sitting in high school classrooms with unfinished homework.

It's funny, my dad is somewhat of a "crackpot"(I am actually glad to be raised by one)... from my youth he always talked about how he has had experiences which lead him to believe he is not fully awake and speculates about how everyone else is not fully awake. I don't take it entirely seriously, but as I've heard it over and over again I've done a lot of thinking on the hypothesis... but no gathering of research so it's probably of no use yet, but good to be reminded about it.

The other thing I want to say, is that I am an extremely gullible person in my natural state. Even though I've been reading this blog for a bit over a year and trying to understand how one applies probability to life, this has been one of the more useful entries. The idea of calculating priors makes much more sense to me- and I think my failure to consistently do so is why I have been so gullible! Post-prior calculation, I seem to be a pretty decent reasoner (like you are in dreams, haha). So I just want to say thanks for bringing this up, it really helped me understand, and will help me explain to other people. I also hope that a lot more posts are done on helping calculate priors.

Sorry, the snark potential here is too high, so I need to get these off my chest.

I dreamed that the Wall Street Journal had published an article about "Eliezer Yudkowsky", but it wasn't me, it was a different "Eliezer Yudkowsky", and in the dream I wondered if I needed to write a letter to clarify this.

Um, the advantage of your name -- and mine -- is that you pretty much never have to worry about this happening. Low prior indeed!

the dream couldn't be evidence because ... only actual sensory impressions of Google results could form the base of a legitimate chain of inferences.

Yeah, I can see why you're worried people might quote you without permission! I mean, I thought I'd seen the worst Google fanboys, but never before did I see anyone claim that Google was the genesis of all valid inferences!

I've often suspected that dreaming consists mostly of the brain's "confabulation" module being fed semi-random noise. Thus, the dreaming brain would be able to look for explanations and arguments, but not generate new hypotheses.

Under this hypothesis, I suppose it actually speaks well for Eliezer that his rationalizing mind prefers to throw its hands up and opt for indecisive confusion rather than accept a silly explanation.

But with a damaged intuition for the prior probability, my mind didn't successfully >check itself, or even notice a problem - didn't get as far as asking "But what is the >prior probability?"

Ok, but in this case it seems that you took the correct action - don't worry about it - and so it is not clear if this is a valid criticism. Even in terms of application of scarce brainpower, it seems to me that dismissing further worry by means of "low prior probability" is about the same amount of work as dismissing by the likelihood ratio, so once your dreaming mind has started considering the problem, there is no course more optimal than dismissing it and the path taken is not relevant. No?

I was just thinking "they already do apply the 'too implausible' heuristic to space aliens and bigfoot", but considering further, no they don't. They apply the silliness heuristic. Things with p = tear up all of physics (ghosts) get bundled with p = an unusual animal good at hiding (Loch Ness Monster) and things with p = near certainty unless civilization destroys itself (AGI at more than human level). Those things are silly, dismiss them.

I suspect this applies to everyone, including you. Even you don't routinely use prior calculations as a heuristic, you dismiss things as silly. The difference being that you try to calibrate your sense of silliness. Sleeping switches it off, leaving even you defenseless.

Also explains how religious people are consistently almost-atheist. The other religions have silly characteristics (how many arms?!). Ours is pre-defined as sensible, so we never get as far as searching it for silly characteristics, indeed it would be silly to try.

One spooky experience for me was when a dream had a high prior probability, and was backed up afterward by unlikely supporting evidence.

My family was living in a rent house for a few months before moving to a new home (was about 9 at the time). I had noticed an uncomfortably large number of scary-looking pests around the house.

Then I had a dream that I had woken up in my bed (likely) and saw a little dark mouse (likely) at the doorway, which then charged toward my bed, jumped up on it (not likely, but I didn't realize mouse limitations then), ran over to the other side, lingered by the pillow for a second, and then jumped off and ran away.

I told my parents the next morning that "It's getting really bad because now I'm seeing mice." And they didn't believe me. So I said, no, it was there, it must have left evidence. So we went back to the scene and looked in the side of the pillow where it had lingered. There was a small opening to the pillow's feather-like down, and right at the opening, there was a black strand of down, while every other piece was white. The black piece looked like it could pass as having been some animal's fur.

In retrospect, the black piece was probably not fur anyway, and the mouse probably wasn't there (again, can't jump that high), but that was pretty freaky.

Why are you so concerned with being able to maintain rationality even in altered or brain-damaged states? This has come up in different contexts in several recent posts.

It seems like an unnecessary bit of rationalist machismo. It's enough of a challenge to create rational, intelligent work when at normal functionality, optimizing for ability to withstand brainwashing or brain damage doesn't seem to me to be an important priority.

Does it have something to do with wondering whether you are now in a diminished state, simply due to humanity's inherent biases and frailties?

Conversely it could just be a matter of habits playing out in in my dreaming self; that I habitually pay more attention to arguments than priors, or habitually evaluate arguments deliberately but priors intuitively.

From what I've read of lucid dreaming, one of the standard techniques is to periodically & habitually do 'dream checks' in the hopes that while asleep one will out of habit do a dream check, realize it's a dream, and then do whatever. This seems like a fairly complex mental argument, and similar to what you did.

Well, the probability that I would dream about a WSJ article like that, given that a WSJ article like that actually exists in this morning's paper, is the same as the probability that I would have such a dream, given that no such article is in this morning's paper. So by Bayes's Theorem, the dream isn't evidence one way or the other.

Very weak evidence, but not quite zero evidence, I'd say. Maybe there was something you saw/heard subliminally but didn't consciously notice...

Over this past summer, I decided to do some tests with my dreams. Overall this has gone nowhere (it doesn't help that I've had difficulty keeping myself motivated enough to keep it going for long). I didn't put it in Bayesian terms at the time (despite having been reading LessWrong), but ignoring weak priors is one of the biggest rationality fails I've experienced in dreams (I've documented quite a few incidents). There have been some cases where I have done something resembling updating dream priors, specifically as it relates to elevators, as there was a period from 2004-2006 in which elevators in dreams would frequently behave in an unrealistic manner (traveling more floors than would make sense, usually down, or having the door or floor become structurally unsound). It got to the point that I actively avoided elevators in dreams if I was interested in the situation I was experiencing. I've sort of half-tried for lucid dreaming, and consequently only been sort of half-successful. I've found that anxiety almost always outweighs desire when it comes to influencing the experience. I did try a little test where I would try to will the time on a display to be a particular number, then checked to see if it worked. I tried this several times, but by the time I remembered to write down my results, I only remembered two of the trials (though I do remembering them being pretty representative of the rest of them). I was able to get the time to appear close (no more than five minutes off, and usually much closer) to the target. I'd like to do an experiment involving my vision, but that's proven much more difficult than I'd like. My left eye has been nonfunctional since birth, my right eye started scarring around age 3, stabalized at "I could read subtitles if you pause the video, give me inch-thick glasses and let me sit close to the screen for a couple minutes", then dropped rapidly toward useless after I visited Las Vegas at age 14 (there are several factors that probably came to a head with that incident). Vision in my dreams took much longer to decline, but gradually got to the point where clear visuals are a novelty even while asleep.

They don't "wake up completely" and realize that, in the absence of evidence, the whole thing has a prior probability too low to deserve specific attention.

"a prior probability too low to deserve specific attention" is an advanced argument, and it is not a generally accepted or well-known principle of reasoning, and it is my impression that humans rarely use it.

It's dangerous to take any lesson from your own dreams, except a general warning that the mind plays tricks.

My dreams are disjointed, incoherent, frustrating sequences of events that could never happen in real life. For example, wandering through an indoor park full of acoustic shells and bumping into a killer whale, walking on its tail.

The closest thing to what you describe was dream in which I kept "waking up" just enough that, within the dream, I collapsed with fatigue and taleported into a bed (not my own).

Despite my actual dreams being bizarre, I've several times had false memories of banal dreams in the form of Déjà vu.

dreamers vs theists:
Without an explanation for the origin of a hypothesis, its mere existence is evidence. If the dreamer believes dreams are random, that's enough. The theist needs a psychological or sociological explanation for the belief. (But the theist acknowledging lack of evidence should at least stop favoring the birthright religion and go the Unitarian route.)

The next level's feat must be the ability to maintain sane thinking in one's sleep.