Monday, January 07, 2008

How I Know I'm Not Dreaming (I Think)

I'm not dreaming. Neither are you.

Oddly, the second sentence seems to be self-confirming in a way the first isn't -- if it refers to an actual "you", that is, if anyone other than me actually reads the sentence, then the sentence must necessarily be true (barring paranormal dreamer-to-dreamer communication). But of course this doesn't imply that I have any special knowledge of your waking state. It's merely a trick of language....

How do I know I'm awake? Responders to the previous post, and others I've questioned, tend to offer the following grounds for knowing:

(1.) Sensory experience is more vivid or detailed in waking than in dreaming. The pinch test may be a version of this. Some claim not to feel their feet on the floor or to be pained staring at the sun. Others say the wide panoply of current visual experience would be impossible in sleep. (Jonathan Ichikawa has recently been arguing that it's not even sensory-like experience we have in dreaming but rather only imagery.)

(2.) Sensory experience is more stable and organized in waking than in dreaming. Some people, for example, say that the words on a page (or on a computer screen!) won't stay still during dreaming, or that a clock's time will be strange or blank or keep changing.

(3.) I cannot do some actions that I can ordinarily do when I try to do them while dreaming -- for example, I can't fly.

Now, I'm inclined to dismiss (3). Maybe, if I can fly, I can rightly conclude that I am dreaming, but the reverse doesn't seem to follow. I suspect that it's perfectly normal to have dreams in which one cannot fly, etc., even if one wants to (unless, perhaps, one realizes one is dreaming and so takes command of the dream, as in lucid dreaming).

(1) and (2) are more tempting. In fact, when I started planning this post I thought I might go for a version of (1). But here's my problem: I go to a quiet place and close my eyes. I still feel quite confident I'm awake. But my visual experience is not very distinct or organized -- certainly not so distinct and organized that I couldn't imagine my brain producing just such experience during sleep without the aid of external input. My auditory experience is pretty vague and thin too. I feel my feet on the floor, of course. But could it really come down to such a slender thread? Is that really my only basis for knowing I'm awake? What if I found a way to deprive myself of vivid or organized tactile sensation too (e.g., by floating in water)? Would I then have no basis for knowing whether I'm asleep or awake?

So maybe we should consider:

(4.) There's some direct and intrinsic knowledge we all have when we're awake that we're awake -- knowledge that's somehow immediate, not on the basis of anything sensory or quasi-sensory.

I point out that accepting some version of (4) -- or (1) or (2) -- does not imply that I can always know that I'm dreaming when I am dreaming. In dreams, we are often confused and leap to weird conclusions. This fact no more undermines my coherent, unconfused present knowledge of my wakefulness than the fact that a deluded, confused person might mistakenly think he's a philosophy professor undermines my non-deluded, non-confused knowledge that I'm a philosophy professor. Our opinions are differently grounded.

Now I wonder where in the philosophical or psychological literature we can find someone who develops an idea like (4). No one comes to immediately to mind, but surely there's someone....


Sammy D said...


Thanks for the reply to my comment on the previous post. This board is empty so I figured I'd respond on this fresh page.

I am as confident about being awake as I am about the existence of God!

I have met many pious individuals that are extremely dedicated to their faith (almost fanatically so), but despite their reassuring confidence about the existence of a higher being, they have no true knowledge of the metaphysical - asking one of them to prove it usually leads to some sort of dismissal of the question.

This is because fact is grounded in empirical data, and claims about the metaphysical simply cannot be tested scientifically. So, whether or not God exists is a question that cannot be addressed within the scope of human knowledge. In the same spirit, whether or not I am dreaming now (and yes, whether or not I am a brain in a vat being manipulated by genius scientists from Alpha Centauri) is a metaphysical proposition that humans simply cannot address scientifically.

I agree with your observation that most people do have a sense of confidence about their being awake, but is this any different from a confidence in the existence of God? Is supposing that we have some kind of intrinsic knowledge anything but a metaphysical assumption akin to an assumption of higher power?

Justin said...

I'm surprised no one gave my answer--I'd assumed I'd just be repeating what others said if I did. I suspect it's similar in import to #1.

Anyway, when I dream, I never have a detailed set of memories about what I've been doing, how I got where I was, etc. Not that in the dream I stop and think "how did I end up here," but that passivity is itself a little odd. In ordinary life, I'm more self-aware than to just let the odd events that happen in dreams go by without comment.

Of course, that doesn't tell me from instant to instant whether I'm dreaming, since I don't constantly stop to ask myself "how did I get here?" But if I reflect, I can produce a wealth of detail that I can't when I'm dreaming.

Jonathan Ichikawa said...

Have you read Ernie Sosa's stuff on this? Chapter 1 of his new book. I read his view as a version of (4).

onclepsycho said...

Here is a variant of your question. People with severe anosognosia vehemently deny that they are hemiplegic, they reject all evidence that goes against their delusion. So, how do you know you are not paralysed?

Jonathan Ichikawa said...

I don't understand the question, onclepsycho. I know I'm not paralysed because my body parts move when I try to move them. That there are people who are delusional about parallel sorts of things is not obviously relevant.

(Compare: some people who are bad at logic think that instances of affirming the antecedent are valid. So, how do you know that affirming the antecedent is invalid? Answer: by manifesting a competence you have -- this is unthreatened by the fact of other people who don't have it.)

KenF said...

Just to talk about flying, I've actually been in a lucid dream and tried to make myself fly and failed. I thought to myself "I'm in a dream I should be able to do fun stuff like fly" and found that I couldn't. It was disappointing. ;-)

Eric Schwitzgebel said...

Thanks for the comments, folks!

Sammy and Oncle raise a similar point, about people being confident in things that are false. I tried to address that idea somewhat with my remark in the post about a deluded person's belief that he's a philosophy professor not undermining my own (differently grounded) knowledge that I am a philosophy professor.

I agree with Jonathan's comment on this. If there is a solid basis for belief that I am awake, I can know that I'm awake on this basis, even if others falsely believe they're awake, on other bases.

But I'll grant Sammy and Oncle the following: My confidence alone is insufficient basis. My dialectic position is that I'm assuming I know that I am awake, and then inquiring what the grounds of that knowledge might be. If you want to challenge that assumption, fair enough -- but that's a different question.

Justin: I agree there certainly is something different in the ordinary cognition of a dreaming mind and a waking mind, especially having to do with the ease with which the dreamer accepts change and incongruity. But I don't know if I quite agree with your formulation of it. Right now, I don't have a detailed set of memories simultaneously before me -- only a few. And so also, it seems plausible to suppose, when I'm dreaming. In both cases, when I inquire as to how I got here, I can (often) seem to recall something about that. But this isn't to say that there's no difference between how memory is experienced in dreams and waking. Hm....

Jonathan: I agree with your comments. Thanks for the tip on Sosa. I haven't looked at his new book yet. I've read an article or two of his on dreaming which I confess I don't remember very well, so maybe that planted the seed of (4) in my mind without my recalling the source.

Eric Schwitzgebel said...

Thanks for the confirmatory anecdote, Ken!

onclepsycho said...

Well, I think that's the whole point of the dream/awake puzzle. If you can't access crucial aspects of self-knowledge in certain states of epistemological closure (dreaming, anosognosia, dysrationalia in your example, or well, just plain stupidity), then how can we be sure that we are not in a similar state in different contexts? Of course, you could gain external information, or have a crucial insight (if that's what you mean by "manifesting a comptence you have"), or be corrected by someone else, but this is just begging the question: the problem remains, how can you be sure that whatever new information you gain is not part of the trick? I am the contrary of a lucid dreamer: In my sleep, I very frequently find myself convinced that my dreams are NOT dreams, and I have recurrent false awakenings, where I tell myself that this is NOT a false awakening. So, while I am quite confident that I am not dreaming right now, I also know that I am recurrently wrong despite having the (presumably) same certainty. I don't think the analogy with severe anosognosia is a bad one, although maybe it is better to constrain it this way: if you're a neuropsychologist (and an expert on anosognosia who has seen many of very impressive cases of denial of hemiplegia) and find yourself in the hospital with a right hemisphere stroke but no hemiplegia, would you be so sure that you are indeed not paralysed?

(Btw, I just found your papers from Eric's link, sounds like very interesting stuff!)

"I'm assuming I know that I am awake, and then inquiring what the grounds of that knowledge might be. If you want to challenge that assumption, fair enough -- but that's a different question."

I cannot see why this is a different question. Isn't the whole point of inquiring about the grounds of your belief that you are awake the same thing as finding out whether you could be wrong?

Jonathan Ichikawa said...

The beginning of Ernie's book is definitely worth checking out on this issue. I might humbly add a suggestion to check out my response to Ernie here:

Anonymous said...

Eric writes, "Now I wonder where in the philosophical or psychological literature we can find someone who develops an idea like (4). No one comes to immediately to mind, but surely there's someone...."

In _The World as Will and Representation_, Schopenhauer argues that the only ground for knowing that we're awake and not dreaming is immediate *feeling*.

The subjective character of a conscious waking state *feels* different than a conscious dreaming one, just as anger and jealously *feel* different to the subject who experiences them.

(Incidentally, it's much more difficult to distinguish anger and jealousy than it is to distinguish waking and dreaming!)

Anyhow, Schopenhauer also recognize that the skeptic can hack at windmills with his dream hypothesis till his arms fall off. But as Schopenhauer says, he who believes he's dreaming when he's awake doesn't need an argument; he needs a cure.

While Schopenhauer is correct about the subjective character of mental states and how we discriminate between them, he doesn't explain why wakefulness *feels* different than dreaming.

Which brings us to Searle.

In _Intentionality_ and other works, Searle argues that visual experience has a self-referential causal structure. Part of the content of the visual experience of a red wheelbarrow is the fact that the visual experience is caused by the red wheelbarrow. If it's not caused by the red wheelbarrow, then the subject of the visual experience is either hallucinating, dreaming, or mad.

Dream experiences, then, feel different than conscious waking ones because the self-referential causal structure of perception breaks down.


Joshua Rust said...

Perhaps the very fact that we can make a meaningful distinction between dreaming and not dreaming in the first place provides a further, perhaps less direct proof that I can distinguish a dream state from a veridical state. Without this ability, these descriptors would have no purchase on us (in which case, we might left to wonder what distinction questioner could possibly have in mind).

The same point can be made in the following, slightly more hyperbolic way: if I know what I mean when I ask, "How do I know I'm not dreaming?," I can know that I'm not dreaming.

KenF said...

I think people have pointed this out, but it's important to remember that the philosophical question "is life a dream" is different from the pscyhological one "how can I tell whether I'm dreaming".

Eric Schwitzgebel said...

Anonymous: Thanks so much for the tips on Schopenhauer and Searle! I confess I haven't spent much time with Schopenhauer. This a good excuse to crack out that old book. Searle I've read quite a bit, though. He was one of my advisors. I'll have to check out whether the self-referential business does address the issue I have in mind. (It's not obvious to me from your description of it.)

Josh: That's beautifully put. That's a great one-liner you've ended with! You sure Wittgenstein didn't say that? ;)

And yes, Kenf, it seems to be easy for us to fall into the more typical -- perhaps more fun -- philosophical question, rather than the more specific, pedestrian question that I intended. (Not that I mind too much.)

MT said...

I'm thinking #2 just about says all there is to be said, if we allow that "coherence" includes autobiographical coherence. By #2, we only need to reflect on whether the present jibes with the past. If awake and not drunk or enraged or otherwise "not truly ourselves," we can expect to have the run of our experiential memories, which exhibit gazillions of physical and social patterns. When some beautiful and popular classmate you have longed for through whole the last year of your still sexually naive life agrees to participate in something that could be construed as a date or suddenly kisses you in a way unlike when your mother or father kisses you, you are liable to wonder momentarily if you're dreaming --because it so starkly contrasts with the principles of social interactions for you as you have inferred them up to now from patterns. Then it might occur to you this kiss is like something you've seen on TV or between your parents in a moment you caught them unawares--as in the way that the memory or memories of having dreamed before enable us to realizing that we are dreaming--and our sense of the situation is supplanted by another one. So if the mental act of reflection and the resources of memory are tickets out, do facsimiles of these tickets appear in dreams? I don't think so. I think my credulousness dreaming might well enable to me to believe that I have--in an imaginary recent past that was not in my dream--reflected and remembered; especially, if to believe otherwise would signify to me that I'm dreaming. But could I dream I am actively reflecting and pursuing patterns in my remembered past experience of being awake? I doubt it. That's how I know I'm awake and not stoned and am myself today--and how I crawl out of it. Reflection produces the so-called sobering thought. "Am I dreaming?" on a post-it is a call to reflect.

MT said...

Or here's a short answer to "how I know" I'm not dreaming:

By ongoing experimentation.

MT said...

I guess reflection in the way I've been mulling it is effectively a mental or cognitive pinch test and/or a hypothetical explanation of why a pinch test works in terms of what mental machinations follow from the pinch that lead to enlightenment. i.e. on reflection, pinches hurt, or they have a memorable feel to them. Pinch-test proponents must assume that a dreaming brain lacks the wherewithal to self-convincingly conjure that feeling. I'm saying it lacks the wherewithal for reflection, of which assessing a putative pinch is a special case, I could say. I realize with "reflection" I'm using a fuzzy-seeming word to group disparate-looking stuff categorically, but maybe you'll come to share my feeling that it's up to the task on reflection.

Reality Handbook said...

As someone who lucid dreams on a nightly basis, I do actually ask myself frequently while awake "how do I know this isn't a dream"?

Usually it's pretty obvious; waking life is measurably more "solid" and continuous than dreams. I can usually reflect on the entire sequence of events which landed me in a particular place--or look in a mirror and check that everything is as it should be. Yet my dreams vary in their solidity, and I've actually found that they have become more solid as years have gone by! The gap is narrowing, especially in terms of the ability to read and handle objects in a stable fashion.

As I probe dream environments with most of the memory and intellect that I possess while awake, I've noted that sometimes certain rules (e.g. gravity) apply...and sometimes they do not. It's as if I am finding my consciousness landing in different types of universes...some of which have "frameworks" installed and others don't.

The closest analogy I can think of comes from computer software and operating systems. If someone is used to a Mac and finds themselves on a Windows machine, then some of the knowledge will will behave in a similar fashion (dragging icons might work, double clicking to launch things). But if they find themselves at a UNIX command line prompt they are in an environment where the only thing they are likely to recognize are words...the mouse will do little or nothing. It requires getting used to a new paradigm.

And so I would say: we should not discount the intrinsic "reality" or "relevance" of the dream paradigm, just because most people seem to be unconscious while examining it. The reports of those who aren't unconscious might help us understand it...per my journal.

Eric Schwitzgebel said...

Thanks, Reality, for that helpful and interesting comment. It's good to hear on this matter from a regular lucid dreamer!

MT: Your point about coherence over time is a nice one. When I originally conceived the post, I had planned to address this a bit. I think if you give me memory, you do give me the resources to make the distinction. But then the problem is, can you give me memory, for the sake of addressing the question of how I know I'm awake? Or is appealing to memory in this context somehow cheating? Well, I can't say I've made the boundaries of the inquiry very clear!

MT said...

It felt natural for me to make the memory move, even thought it occurred to me later that it wasn't a traditionally philosophical one, because I was thinking of brains rather than minds and assuming conscious thought to be a more-or-less fixed brain-stem process in collaboration with a varying number of cognitive and/or anatomical modules, and collaborating less in REM than while awake (that last point especially being suggested by recent experiments). I don't actually know that memory work or any proposals ala global workspace theory would make my move any more natural. It's more like in the spirit of this stuff I felt free to treat it as an independent thing.

Derek said...

There are a lot of people that would love to learn how to lucid dream as often as possible, and these people have found many methods of inducing them. Their most basic trick is the "reality check," a little test they use to determine whether or not they're dreaming. They've found that if you make reality checks a habit, you begin to use them in your sleep, fostering those "Wait a second, I'm dreaming!" moments. These checks are based off of little reliable differences between waking experience and dreaming experience.

Most reality checks are based on an assessment of one's environment. One popular one is to look at a clock, look away for a second, and then look back to see if the time has changed, as clocks tend to change time randomly in dreams. It's said that light switches usually don't work in dreams, so people will often turn a light switch off and on to see if it functions properly, and assume that a malfunctioning light means they're dreaming. That one's not my favorite; I snicker at the thought of a waking onieronaut encountering a power outage.

Interestingly enough, some reality checks are based on an appraisal of one's own body. One common reality check is to look at one's hands, as they tend to take on an unusual, warped appearence in dreams. People talk about seeing extra fingers, blue skin, and other psychedelic qualities. In another check, one pinches one's nose tightly and then tries to breathe through it. It's said that in a dream one will be able to breathe fine through a closed nose.

I can't speak for the validity of any of these checks, as I've never used them personally, but a large number of people swear by them.

Eric Schwitzgebel said...

Yeah, MT, I think the question is interesting either way -- whether you take memory for granted or whether you assume that the question of justifying your judgment that you're awake necessitates also simultaneously justifying your sense of what you remember.

Thanks, Derek, for that info about lucid dreams! Even such reality checks function some percentage of the time in inducing the recognition that one is dreaming when one is dreaming, the rate of false positives and false negatives may make an epistemologist worry.

Anonymous said...

It's a fascinating question, to be sure.

My dreams usually—though not always—diverge from reality in some obvious manner (an example might be that I can fly, or that there is some fundamental breakdown in causality). However, I see no reason to suppose that it is impossible that the "real" world around us could at some point do the exact same thing.

Indeed, I distinctly remember once finding that I was looking down on myself and the members of my family that I was with from a position approximately one metre above and to the left of where my head was. I certainly wasn't dreaming at the time and I have no adequate explanation for such an event.

So I am not sure that it is possible to be entirely certain that one is or is not dreaming. The breakdown of causality is probably the number one indicator for me that I'm dreaming and not awake, but I don't know that it's possible to completely rule that out in the real world (I rather hope not, but that is just my hope, not a fact).

Jessie said...

My intuition is that there must be some sense that transmits the direct knowledge that we're awake when we're awake.

I think that there's some process in the brain that is constantly testing the "realness" of experience. I also think perceived realness must be a continuum, with the hypervigilant flight-or-fight state on one end, and dreams on the other.

Sometimes when I'm in a normal awake state and engaged in a task like working or driving, I feel little blips in my perception of "realness", as if part of brain was about to register that I am less awake than I really am, but some other internal process caught it and corrected it. This discrepancy sometimes causes a small adrenaline rush, as if my brain is saying, "...oops!"

It's very weird and disconcerting. I should add that I take medication for anxiety and depression, and I think this experience is likely a symptom of either the medications or the pre-existing psychiatric conditions.

It's as if my brain tests, "is what I'm experiencing real?", receives an answer, "no", starts to initiate a physiological response, and then a failsafe kicks in that says, "yes, this IS real, you ARE awake".

I wish I could do a better job of describing it!

Anonymous said...

There is some truth in your fiction, and some fiction in your truth.

Denver said...

All that has been said is true, but it only remains true so long as your dreams are not as real as reality. Ever woken up from a dream in your own bed only to find out a few moments later that you are still dreaming. I have. In fact I have had this dream many times in a night and remembered it very clearly, and on more than one occasion it has gone on for more than a few minutes. After nights like that I wake unsure if I am awake and unable to test it. After you have such dreams a few times you start thinking in the dream, "i must still be dreaming" and test it, sometimes the test works and you find that you are dreaming, but after a while the tests don't work and you assume you are awake only to wake up later. At this point in my life I have simply come the conclusion that I don't know if I'm awake but can usually be mostly sure that I am. For all I know though, all of life could be a big dream, but its better not to chance it, and what difference does it make anyway? btw I'm mildly schizophrenic.

HiMyNameIsDead said...

One time I had a dream where I was dreaming for awhile,woke up and eventually asked "Am I dreaming?" and I reflected on the thought,on my current way of rationalizing and what I considered logic,and it still made perfect sense! Though everything was different,the dream still made sense;my way of thinking didn't change, it didn't become a lucid dream and I didn't wake up.. The dream resumed and eventually I woke up. Now can you imagine how messed up I am thinking about how I can't even know anymore whether or not I'm dreaming? Because in my dreams I've felt pain. In my dreams,horrifying things don't cause me to wake up. In my dreams, I wished to wake up if I were dreaming,or for there to be a sign, or for pinching myself to cause a change,something logically inconsistent to be noted,but it didn't.. I gained no power,and things stayed the same. It was horrific then and it is even now,in retrospect,because for all I know this could be a prepetual nightmare... I had a past in my dream to make my logic relevant,I have that same depth to my past now.. I analyzed myself then as I do now,but it didn't matter.... Just be glad you don't have dreams like I do.

Dunno if it's relevant but I have dissasociative tendencies,am bipolar,ocd,and adhd. I'm also starting to think playing the game "yume nikki"(dream diary) is causing me to lose what's left of my connection with "reality" because the main character's role seems exactly like my real life x.x

If you guys can offer me some advise or something,please do D:

..I'm so afraid of this become unreal,and it is... everything is losing meaning to me :(

Anonymous said...

What if i can fly in real life anyways then what do i do?

Anonymous said...

"Jonathan Ichikawa has recently been arguing that it's not even sensory-like experience we have in dreaming but rather only imagery.)"

Then this person has little dream experience, and no Lucid Dreaming experiences. I am of the opinion that if you haven't experienced it, than your thoughts on the matter are of little importance, and should not be taken as anything like a valid point. I KNOW that this comment of his is false.