How Do You Know You're Not Dreaming?

Things are quiet. People are on break -- visiting family, like me -- or they're sweating it out at the Eastern APA.

But maybe some of you visitors will do me a favor and answer this: How do you know you're not dreaming? Presumably you do know, right? Genuine radical skeptics are few. What I'm asking is how you know -- on what basis or by what means.

I have my own opinions about this which I'll post later, but first I'm curious to hear from some of you....

Ho Ho Ho!

was the Christmas greeting my mother -- a statistics professor -- sent me.

To which, of course, the only possible reply was H_a H_a H_a.

(If you don't get the joke, this might help.)

Introspective Infallibility, Causation, and Containment

In his second Meditation, Descartes gives the impression that he thinks self-knowledge of current conscious experience is indubitably certain, immune to error, infallible. (Whether he consistently espouses this view throughout his corpus is another question.) Ever since, infallibilism about introspection has been a mainstream position in philosophy of mind -- sometimes dominant, sometimes (as now) out of favor but nonetheless with prominent proponents.

If we suppose that introspection is a causal process between two distinct events, it's hard to see how infallibilism could be plausible. What sort of event can't be brought about in strange ways? If we suppose, for example, that introspective judgment is a brain process, couldn't -- at least in principle, by dint of genius neuroscience, but probably much more easily than that -- that brain process be brought about non-standardly?

One way out of this is to deny that the introspective judgment and the introspected conscious experience are indeed distinct events ("distinct existences" in Shoemaker's sense). For example one might "contain" the other, as is sometimes suggested (e.g., Shoemaker, Burge). Consider as an analogy: "This sentence contains the word 'pixie'". The sentence is infallibly true wherever it appears because the conditions of its existence are a subset of the conditions of its truth. Could introspection work the same way?

Well, one fella's modus ponens is another's modus tollens: If containment implies infallibility, the case against infallibility is, I think, so compelling that we ought to deny containment. But let's consider containment independently of that. Does the judgment, "I'm visually experiencing redness" (for example) contain a visual experience of redness? Does it itself, somehow, contain the phenomenology of red -- not merely assert the existence of red phenomenology but actually include that phenomenology?

Let's suppose -- I don't quite buy this, but it's probably close enough for the purposes of this argument -- that the components of judgments are concepts. Concepts may be reshuffled and combined to make new judgments, right? Now the judgment "I'm visually experiencing something caused by Martians" cannot literally contain something caused by Martians because nothing is caused by Martians. And the judgment "Looking at Mars can cause people to visually experience redness" cannot contain an actual experience of redness because it can be uttered by a blind woman. But now we can recombine elements of the two to get "I'm visually experiencing redness". It's odd to suppose that this recombined product must contain actual red phenomenology if it's composed only of elements none of which contain that phenomenology and that can occur independently of it.

Or: The judgment "I visually experienced redness" does not contain red phenomenology (since I might now be experiencing no redness). Similarly for the judgment "I will visually experience redness". Is the present-tense version of this judgment so radically different in structure from the past and future tenses that it must contain redness -- a totally different kind of thing from what the others contain -- while the others don't?

The most plausible case for something like containment might be the following (bastardized and simplified from Chalmers 2003): "I have *this* phenomenology" -- where *this* is an act of "inner ostention", cognitively pointing toward one's own phenomenology. Such a case might be a case of self-fulfulling containment, but it is no more substantive or necessarily introspective than "I'm located here".

Links to Advice on Philosophy Grad School Applications

from the Leiter Reports, here. I also ran a series of posts about applying a couple months ago.

I'd wish all applicants good luck, but I wonder if there would be some sort of paradox in doing so!

Artists Don't Know Better Than the Rest of Us How Things Look

It's almost a ritual, in discussions of the phenomenology of vision, to praise "artists" -- meaning those in the visual arts -- for having an appreciation of visual phenomenology that most of the rest of us lack. However I believe that the truth is the reverse.

Thomas Reid is typical:

I cannot therefore entertain the hope of being intelligible to those readers who have not, by pains and practice, acquired the habit of distinguishing the appearance of objects to the eye, from the judgment which we form by sight of their colour, distance, magnitude, and figure. The only profession in life wherein it is necessary to make this distinction, is that of painting. The painter hath occasion for an abstraction, with regard to visible objects, somewhat similar to that which we here require: and this indeed is the most difficult part of his art. For it is evident, that if he could fix in his imagination the visible appearance of objects, without confounding it with the things signified by that appearance, it would be as easy for him to paint from life, and to give every figure its proper shading and relief, and its perspective proportions, as it is to paint from a copy (An Inquiry into the Human Mind, 1764/1997, p. 82-83).

Now this much I'll grant Reid and others who share his view: Traditional, representational painters have the difficult skill of rendering on a two-dimensional canvas an arrangement of paint such that it produces for the eye an arrangement of light importantly similar to what would be produced by the actual three-dimensional scene they are rendering; and it takes much practice to see outward things in terms of how they can be presented on a canvas, for example foreshortened and rendered in the right two-dimensional shapes. But that skill is not the skill of appreciating real visual appearances.

For one thing, the view makes no geometric sense. Three dimensional scenes cannot be rendered in two-dimensions without geometric distortion in size and/or angle -- distortion that becomes more evident the greater the visual angle encompassed. This is why there is always something a little wrong with panoramic photographs. This geometrical difficulty could be avoided if artists drew on concave semispheres instead of flat rectangles. But they don't; and they'd have to relearn the rules of perspective to do so.

Even setting that issue aside: We should not infer from the fact that to create a sense of realism in the viewer an artist must color shadows in such-and-such a way that we really visually experience shadows as colored in that way. We should not infer from the fact that light, and water, and distance, and motion, can be rendered a certain way on canvas to the fact that our visual experience light and water and distance and motion matches such renditions (e.g., motion as either a series of freeze-frames or as blur). The painter learns the skill of seeing the world in a certain way for the purpose of a certain technique, not the skill of apprehending our visual experience as it is in itself.

Since most visual artists don't seem to appreciate this fact, their reports about their visual experience are likely to be less accurate than the reports of non-artists -- distorted by the false assumption that the world as seen for painting is the world as seen for life.

What Do You Think About When Watching The Nutcracker?

Saturday afternoon was, I think (believe it or not), my first time watching The Nutcracker. My wife, son, and I were bumped from our back-of-the-room seats and compensated with VIP seats, third row center. Early into the performance, I started thinking about the amazing opulence celebrated, maybe even taken for granted, in the ballet; and then about the opulence of symphonies and ballets in general and critics of luxury like Marx and Peter Singer and Mozi. Then I thought about the fact that I was thinking such things, while my wife was simply enjoying the ballet. [Update Jan 15, 2014: I doubt that my wife was "simply enjoying the ballet" (per the discussion in comments below); and I no longer even think I know what it would take for such a statement to be true.] I thought about why boys want to be soldiers, and about changing views of corporal punishment, the strangeness of wanting pearls, the sexuality of the costumes, whether too many pirouettes will damage the brain.

And then I wondered this: What if we gave everyone in the audience "beepers" that went off randomly a couple times during the show, asking people to report on their experiences, thoughts, feelings, sensations, whatever, just before the beep? (You know I've been getting into beepers!) Surely someone has done this sort of thing?

Russ Hurlburt and I have randomly beeped people during our talks. So far, among about 10 beeped experiences we've discussed with audience members, not a single person has reported being focused primarily on the content of the talk.

Prediction: People will, if asked after the fact, report much higher rates of absorption in movies, lectures, performances, etc., than one would see if one did a random sampling study. That wouldn't be a bad thing, necessarily. In a way, it's compatible with a much richer, personal, life-involving experience of the performance....

Consciousness and Rationality Without Language?

A comment on Wednesday's post reminded me of a delightful old case study by Andre Roch Lecours and Yves Joanette (1980) which seems to be largely unknown in the literature.

"Brother John" was a French monk who suffered severe, almost complete, aphasia (that is, incapacity with language) of both outer speech and, by his report, inner speech as well during epileptic episodes. Yet during these episodes he remained quite capable of rational thought and behavior. Here is Lecours and Joanette's description of one extended episode of severe global aphasia in Brother John:

While he was traveling by train from Italy to Switzerland, Brother John once found himself at the height of a paroxysmal dysphasia soon upon reaching the small town of his destination. He had never been in this town before but he probably had considered in his mind, before the spell began (or became severe), the fact he was to disembark at the next stop of the train. At all events, he recognized the fact he had arrived when the time came. He consequently gathered his suitcases and got off the train and out of the railway station, the latter after properly presenting his transportation titles to an attending agent. He then looked for and identified a hotel, mostly or entirely on non-linguistic clues since alexia was still severe, entered and recognized the registration desk, showed the attendant his medic-alert bracelet only to be dismayed and dismissed by a gesture meaning "no-room" and a facial mimic that perhaps meant "I-do-not-want-trouble-in-my-establishment." Brother John repeated the operation in search of a second hotel, found one and its registration desk, showed his bracelet again, and, relieved at recognizing through nods and gestures that there were both room and sympathy this time, he gave the receptionist (a "fat lady") his passport, indicating the page where she was to find the information necessary for completing his entry file. He then reacted affirmatively to her "do-you-want-to-rest-in-bed-now" mimical question. He was led to his room and given his key; he probably tipped as expected and went to bed. He did not rest long, however: feeling miserable ["It helps to sleep but sometimes I cannot because I am too nervous and jittery" (free translation)], then hungry, he went down to the hotel's lobby and found the restaurant by himself. He sat at the table and, when presented with the menu, he pointed at a line he could not read but expected to be out of the hors-d'oeuvres and desserts sections. He hoped he had chosen something he liked and felt sorry when the waiter came back with a dish of fish, that is, something he particularly dislikes. He nonetheless ate a bit ("potatoes and other vegetables"), drank a bottle of "mineral water," then went back by himself to his room, properly used his key to unlock his bedroom door, lay down, and slept his aphasia away. He woke up hours later, okay speechwise but feeling "foolish" and apologetic. He went to see the fat lady and explained in detail; apparently, she was compassionate (p. 13-14).

If Lecours and Joanette's understanding of Brother John is correct, there was no, or almost no, inner or outer speech production or recognition through the entire episode. Brother John was presumbably not "thinking in words" -- or if he was, "thinking in words" must mean something very different from what I'd have thought it to mean.

Of course we shouldn't put much weight on a single anecdote transmitted second-hand....

Perceptual Experience and Attention

I'm drafting an entry for Sage Press's forthcoming Encyclopedia of Perception. Since Sage seems to want a fairly relaxed, conversational style and the draft isn't much longer than a blog post, I thought I'd make it today's post.

Perceptual Experience and Attention

Do you have constant tactile experience of the shirt on your back? Constant auditory experience of the background rumble of traffic? Constant visual experience of the tip of your nose? Or, when you aren’t paying attention to such things, do they drop out of consciousness entirely, so that they form no part of your stream of experience – not even vaguely, peripherally, amorphously – no part of your phenomenology, no part of what it’s like to be you?

There is, of course, perceptual processing without attention. A gentle tug on the shirt or an unexpected movement in the visual periphery will generally call your attention, even if you are fully absorbed in other things. To call attention such events must register, first, pre-attentively. While your attention centers on one or a few things, you monitor many others inattentively, ready to redirect attention when an inattentional processes detects a large or important change. The interesting question is not whether there is perception without attention, but whether experience accompanies our inattentional perceptual processing or whether that processing is entirely nonconscious. We might think of consciousness as like a soup. Is it a rich soup, replete with experience across broad regions of several modalities simultaneously? Or is it a thin soup, limited to one or a few regions or objects or modalities at a time?

Ordinary people’s intuitions diverge considerably here. So also do the views of philosophers and psychologists. On intuitive or introspective grounds, William James and John Searle (among others) endorse the rich view, Julian Jaynes and David Armstrong the thin view. One widely discussed case is the absent-minded driver: You’ve driven to work a thousand times. Today you drive habitually, utterly absorbed in other thoughts. You arrive and seem suddenly to wake up: Ah, I’m here already! Now, did you actually visually experience the road – at all? very much? – on your way to work?

One might think the question easily settled. Simply introspect now. How much is going on in your consciousness? Unfortunately, the “refrigerator light phenomenon” frustrates any such straightforward test: The fact that you hear (or auditorially experience) the hum of traffic when you’re thinking about whether you hear the hum of traffic provides no evidence on the question of whether you hear the hum of traffic when you’re not considering the matter. Just as the act of checking the refrigerator light turns it on, so also might the act of checking for tactile experience of one’s shirt or visual experience of one’s nose produce those very experiences.

Often we fail to parse, respond to, or remember what might seem to be salient stimuli – a stream of speech we’ve decided to ignore, a woman in a gorilla suit walking through a fast-paced ballgame, substantial changes in a flickering picture, a geometric figure briefly presented in an unattended part of a visual display. Daniel Dennett and Arien Mack, among others, have interpreted such phenomena as evidence for the thin view. However, the conclusion does not follow. We may not parse unattended stimuli much or remember them well, but they may still be experienced in an inchoate or immemorable way, or the general gist may be remembered if not the details.

Ned Block has emphasized that it seems introspectively that we visually experience more of a visual display than we focally attend to. On the face of it, this fact (if it is a fact) seems to suggest that perceptual experience outruns attention. But might it, instead, be a matter of diffuse attention spreading more broadly than focal attention, perhaps along a gradient? Even if you visually experience this whole page while focally attending only to a few words at a time, it doesn’t follow that you also visually experience the wall in the far periphery when you’re not thinking about it, or the pressure of the shoes on your feet.

The issue of whether perceptual experience is, in general, rich or thin may also be addressed by gathering introspective or immediately retrospective reports about randomly sampled moments of experience. Eric Schwitzgebel, giving people beepers to wear during ordinary activities and asking them to reflect on the last undisturbed moment before each beep, found a majority of participants to report visual experience in 100% of sampled moments, tactile experience and peripheral visual experience somewhat less. However, as Schwitzgebel admits, it’s unclear how much credence to give such reports.

The rich and thin views draw radically different pictures of our experience. If the rich view is right, consciousness contains much more than adherents of the thin view suppose. Although there is room here for merely terminological confusion, it appears that there is also room for major substantive disagreement. Strange that this question, concerning an absolutely fundamental and pervasive aspect of human experience, is so poorly studied!

Suggested further readings:

Armstrong, D.M. (1981), The nature of mind. Ithaca, NY: Cornell.

Block, N. (forthcoming), Consciousness, accessibility, and the mesh between psychology and neuroscience. Behavioral and Brain Sciences.

Dennett, D.C. (1991), Consciousness explained. Boston: Little, Brown & Co.

James, W. (1980/1981), The principles of psychology. Cambridge, MA: Harvard.

Jaynes, J. (1976), The origin of consciousness in the breakdown of the bicameral mind. Boston: Houghton Mifflin.

Mack, A., & Rock, I. (1998), Inattentional blindness. Cambridge, MA: MIT.

Reddy, L., Reddy, L., & Koch, C. (2006), Face identification in the near-absence of focal attention. Vision Research, 46, 2336-2343.

Rensink, R.A. (2000), When good observers go bad: Change blindness, inattentional blindness, and visual experience. Psyche, 6 (9).

Schwitzgebel, E. (2007), Do you have constant tactile experience of your feet in your shoes? Or is experience limited to what’s in attention? Journal of Consciousness Studies, 14 (3), 5-35.

Searle, J.R. (1992), The rediscovery of the mind. Cambridge, MA: MIT.

Simons, D.J. (2000), Attentional capture and inattentional blindness. Trends in Cognitive Sciences, 4, 147-155.

Note to blog visitors: One aspect of the question I've omitted is the old debate in introspective psychology about whether experiences of objects to which one is attending differ in some qualitative attribute like "clearness" or "attensity" from experiences of unattended objects. But this hasn't exactly been a hot topic in the last 100 years; and the more basic question of whether there even is experience outside of attention needs to be settled first.

Political Scientists' Voting: Predictions and Methods

A week and a half ago, I posted a brief, frustrated reflection on my failure to find any good research on the rates at which political scientists vote in public elections. After several more search attempts, I've given up. As far as I can see, no one has explored this issue since a few studies in the 1960s and 1970s -- studies so problematic as to be utterly useless.

I've informally asked a number of people to guess what Josh Rust and I will find when we analyze the data. Everyone except the political scientists said that they suspect we'll find that political scientists vote more often than other professors. The political scientists, however, were cagey. A couple mentioned a minority view in political science that voting is for suckers: Your vote never makes a difference, so voting is a waste of time. Yet one of these same professors said that he himself has voted in every single election, down to the tiniest little runoff, since the turn of the century.

So here's my prediction: Political scientists will have a more broadly spread distribution than other professors -- there will be more at the extreme of voting in almost every election but there will also be many who vote rarely or never. On average, though, I predict, the political scientists will vote more. Compared to the average non-political-science professor, the average political scientist will be more informed about elections, more invested in and interested in the outcomes, and more likely to have publicly embraced the view that one should vote.

Well, we'll see! Here's what Josh and I plan to do:

From university websites, we'll gather names of philosophers, political scientists, and a sample of professors in other fields. We'll then look for these names on voting records that have been provided to us by several states, calculating a rate of votes per year for each individual since that individual's first recorded vote in the state.

There are two main weaknesses in this method, and I especially welcome readers' reflections or suggestions about these. First, since we don't have street addresses for the professors in question, we will not be able to disambiguate between voters with identical names. If there are four John Millers who live within commuting distance of So-and-So College, we won't know which one is the professor, so we will have to discard the data. And second, if no voting record matches the professor's name, we will not know whether that professor is registered under a different name, registered in a different locale, a non-citizen, a felon, or simply a non-voter. So we'll have to exclude those professors too.

Because of these difficulties, we won't be able to reach conclusions about absolute rates of voting participation among political scientists, just comparative rates -- more or less than professors in other departments. But will these difficulties undermine our ability even to draw that conclusion? Although I don't see any reason to think there will be large differences in the rates at which professors in different departments are registered under different names or in different locales, there is reason to suspect that different departments may have different rates of common names and of non-citizens. But hopefully we can keep those confounds under control: We'll have an exact count of the common-name professors in the different departments, so we can attempt analyses that account for that; and hopefully we can estimate the rates of non-citizenship in departments by accessing c.v.'s or biographies of our non-voting professors where possible and by looking at general data on the citizenship of professors.

What do you think?

Should Philosophy Be Read Slowly?

Non-academics often think that skill in reading is measured by reading speed -- the faster the better. That is partly true, up to a point (up to about 7th grade, I suspect). I'm reminded of Woody Allen's joke about what he got from speed-reading War and Peace: "It's about Russia."

Philosophers, in contrast, sometimes seem to fetishize slow reading. "Deep" philosophy, it might seem -- or deep thinking about philosophy as one reads -- requires a glacial pace. Students sometimes excitedly report, "We spent the whole three-hour seminar reading a single page of Wittgenstein!"

I don't deny that glacial reading can, in the right mood, be exciting. And surely if you breeze through Wittgenstein or Heidegger at two minutes a page, you're missing something. But here's the compromise: If you cut your reading pace in half to get more out of what you read, you'll only be able to read half as much -- and that's another way of missing something.

The key to great philosophical reading, I think, is to vary your pace according to your projects and interests. In some ways, reading quickly is the harder skill. It's also the one less taught in philosophy seminars. How quickly can you assimilate the main ideas of 400 pages of articles on topic X? Can you detect and hone in on, slow down for, those crucial few paragraphs on which the issues really turn? Indeed, unless you can read quickly, you're likely not to have the broad understanding necessary to see where one should read slowly.

I used to begin graduate seminars with student presentations on the assigned reading. The dull blow-by-blow that typically resulted, dedicating an equal amount of energy to every page of the reading, is exactly the opposite of the skilled reader's adjustment of pace and focus. Now instead I ask students to come prepared with one or two well-developed questions or objections. This, I hope, encourages focus rather than plodding. I haven't yet dared to assign students 400 pages of a philosophy for a week, advising them to read it quickly and laser in on what seem to them to be key issues -- I think this might cause a riot! -- but the more I think about it, the more I'm tempted.

Reading philosophy quickly of course invites misunderstanding and oversimplification. But so does reading philosophy slowly, without a sufficient sense of context and alternative perspectives.

Echoes of Inner Speech

It seems to me that I sometimes have thoughts that linger after the inner speech that expresses them is done. I might say silently to myself, "Shoot, writing three posts a week is a lot of work!" and then that thought may briefly stay with me, in some sense that's hard to articulate, before I move on to new thoughts.

Can I say more about what that experience is like? Only through metaphor, it seems: It's like a resonance or an echo. But I don't think the inner speech literally resonates or echoes in the sense of, say, the last word or the last few words quietly buzzing or repeating themselves, slowly dying away.

I found it interesting, then, to contrast this sense I have of my inner speech with a report by Melanie, the subject Russ Hurlburt and I interviewed in our just-published book, Describing Inner Experience?, regarding a randomly-sampled (with a beeper) moment of her inner experience:

Russ: So you had said in inner speech, “they lasted for a nice long time,” just prior to the beep?

Melanie: Um hm, not at the beep but just prior to it.

Russ: But in some way the “nice long time” portion is still there. Is that right?

Melanie: Yeah, it was. The best I can liken it to is an echo.

...

Russ: Okay. And “echo.” I want to understand what you mean by “echo.” An echo gets softer and softer; did you mean to imply that? And echo sometimes is repeated and sometimes once but…

Melanie: No, it didn’t get softer and softer, it’s almost like [quizzically] it got blurrier and blurrier. Not in terms of visual blurry, but a sound blurry [again quizzically], where it just started overlapping itself until it just came to this jumble in which you can’t make any noise out. It sounds really weird but…

Russ: So are you saying that you said in inner speech something that was quite clear…

Melanie: Um hm.

Russ: … “It lasted for a nice long time,” and then there’s “nice long time,” “nice long time,” overlapped with “nice long time”…

Melanie: Yeah.

Russ: … then “nice long time” overlapped with “nice long time” overlapped with “nice long time”…

Melanie: And it keeps going.

Russ: … until there’s sort of several of these things going?

Melanie: Yeah (Sixth Sampling Day, p. 207-208).

In the book, I express skepticism about this report. I wonder if Melanie is being taken in by her own metaphor (as, I think, people are often taken in by metaphors in describing their experience, e.g., in calling dreams black and white or visual experience flat). Russ, however, accepts the report.

What do you think? Any other ideas about the phenomenology, if any, of lingering thoughts?

Synchronized Movement and the Self-Other Boundary

I've been reading The Happiness Hypothesis, by Jonathan Haidt -- one of those delightful books pitched to the non-specialist, yet accurate and meaty enough to be of interest to the specialist -- and I was struck by Haidt's description of historian William McNeill's work on synchronized movement among soliders and dancers:

Words are inadequate to describe the emotion aroused by the prolonged movement in unison that [military] drilling involved. A sense of pervasive well-being is what I recall; more specifically, a strange sense of personal enlargement; a sort of swelling out, becoming bigger than life, thanks to participation in collective ritual (McNeill 1997, p. 2).

Who'd have thought endless marching on the parade-grounds could be so fulfilling?

I am reminded of work by V.S. Ramachandran on the ease with which experimenters can distort the perceived boundaries of a subject's body. For example:

Another striking instance of a 'displaced' body part can be demonstrated by using a dummy rubber hand. The dummy hand is placed in front of a vertical partition on a table. The subject places his hand behind the partition so he cannot see it. The experimenter now uses his left hand to stroke the dummy hand while at the same time using his right hand to stroke the subject's real hand (hidden from view) in perfect synchrony. The subject soon begins to experience the sensations as arising from the dummy hand (Blotvinick and Cohen 1998) (Ramachandran and Hirstein 1998, p. 1623).

Also:

The subject sits in a chair blindfolded, with an accomplice sitting in front of him, facing the same direction. The experimenter then stands near the subject, and with his left hand takes hold of the subject's left index finger and uses it to repeatedly and randomly to [sic] tap and stroke the nose of the accomplice while at the same time, using his right hand, he taps and strokes the subject's nose in precisely the same manner, and in perfect synchrony. After a few seconds of this procedure, the subject develops the uncanny illusion that his nose has either been dislocated or has been stretched out several feet forwards, demonstrating the striking plasticity or malleability of our body image (p. 1622).

So here's my thought: Maybe synchronized movement distorts body boundaries in a similar way: One feels the ground strike one's feet, repeatedly and in perfect synchrony with seeing other people's feet striking the ground. One does not see one's own feet. If Ramachandran's model applies, repeatedly receiving such feedback might bring one to (at least start to) see those other people's feet as one's own -- explaining, in turn, the phenomenology McNeill reports. Perhaps then it is no accident that armies and sports teams and dancing lovers practice moving in synchrony, causing a blurring of the experienced boundary between self and other?