Perspective on a Difficult Idea

Linear perspective is an extremely compelling visual illusion. And it is an illusion. You know the train tracks do not really converge. If they did, the train would derail.

Why do parallel lines look like they converge in the distance? I think it is a learned response to living in a world of pictures. That interpretation is so overlearned, it occurs without explicit awareness. But it should be possible to unpack that illusion.

Linear perspective was invented in the early 1400’s by an Italian architect (Brunelleschi) and simultaneously by others trying to draw and paint, as a way to represent three dimensional space on a two-dimensional sheet. It is a good invention and it works pretty well. We do see "depth" in a flat picture, even though that is not literally possible because there is no depth in a flat picture.

In the 600 years since then, the technique has become so universal that pictures drawn without it don’t look right.











The artist, Albrecht Durer, in a famous 1525 lithograph, is shown using strings to represent the rays of light coming from the corners of his object. His canvas swings out of the way while he sights down the strings to the object. Then he puts the canvas back in place and makes marks where the strings would hit it. Connect the dots, and you have a mathematically correct map of what the actual object looks like from that point of view.

But what is it a drawing of? The sides of a walkway do not really converge in the distance. If they did, you couldn’t walk it to the end. So a perspective drawing is surely not an accurate representation of reality. Strings or no strings, the perspective drawing is a fantasy, like a unicorn. It is something that does not exist in the world.



Why then does the unrealistic perspective drawing look so convincingly real, at least with respect to depth? Is it because when we look at the world we actually see it wrong? When you look down a long walkway, not a picture of one, are you seeing the world wrongly? We know from practical experience in the world that parallel lines do not converge in the distance, so why do we see convergence? We have to make a mental correction: “The sides look like they converge, but really they don’t.”


I have spent a lot of time looking at scenes (not pictures, but situations) where there seemed to be converging perspective lines. Much to my wife’s consternation, I will often stop to stare down a long hotel hallway like the one shown here, and ask myself, “Do those walls really look like they converge, or am I only imagining it?” I will walk up and down such hallways, trying to understand what I am seeing, and hoping I won’t get reported to hotel security.

And my conclusion is this: I do NOT see the walls converging. I can talk myself into it, but if I turn off my metacognition, what I see is a continuously unfolding horizon and continuous visual information moving around my head. At no time do I worry that the walls are closing in on me.

If I stand motionless and look down the hall as if I were a camera taking a picture, then I CAN see convergence. But that’s because I am pretending to be a camera. I am using metacognition, the ability we all have to introspect on our own mental experience. Metacognition is what allows you to answer the question, "What are you thinking about?" To answer, you must think about your thinking process. For a visual scene, the question, "What do you see?" encourages metacognition. You must think about your visual experience. Instead of just having a visual experience, you are now one step removed from it. You have stepped back from your natural experience and instead you are now using metacognition to examine your own mental imagery.

We learn visual metacognition when we learn to understand pictures. For the last six centuries virtually all pictures used the linear perspective technique of representation, which is derived from metacognition, not simple visual perception.

It is extremely difficult to set aside the ways of seeing that you have unconsciously assumed all your life and which your culture claims is the “correct” way of seeing. When you look at a photograph, you automatically apply metacognition – actually you must. To understand a picture, you must abandon your natural, egocentric point of view and take up the special imaginary point of view implied by the picture so you can imagine you are looking at the scene depicted. It is a sophisticated shift in personal frame of reference, but we do it with ease.

It looks like the perspective lines are “in” the photograph because that’s how we have been taught to interpret such artifacts. A photograph is a 2-dimensional representation of a three-dimensional scene, so we apply Brunelleschi’s rules to it. Whipping out a Sharpie and drawing the perspective lines on the photograph only proves my point that we are using an artist’s metacognitive way of seeing the photo. But we don't normally do that when we are using ordinary cognition, as opposed to metacognition, in the real world.

When I look down the grocery aisle as if I were a camera, I am strongly tempted to see converging lines. Look at them there in the picture! I can do that, but why would I?

Never, when I have been shopping for a box of pasta, have I experienced converging parallel lines. Never. I just go to the pasta section and get what I want, and proceed to the next aisle. Not a single time have I worried if my shopping cart would fit out the narrow opening in the far end of the aisle. Linear perspective just does not come up when you need a box of pasta.

However, if I stand at the head of the aisle and imagine I am a camera, or an artist, and mentally "step back" from my experience, then pop! There are the convergence lines. But they are purely an intellectual, metacognitive, culturally contrived way of seeing, an overlay on my natural experience. I have been taught to see convergence lines and so I do. But when I do, I am not looking at the world any more, but instead, looking at my own mental imagery of the world.

Now that I have learned how to unlearn that cultural habit, I no longer see perspective lines unless I want to. That demonstrates to me that apprehension of linear perspective is not a native property of the biological visual system.

Discussions of the perspective illusion always present pictures to illustrate the points being made. I have done that here, too. I admit that the convergence lines are there in the pictures. Of course they are. But that’s because they are pictures! Metacognition is required to understand pictures, just as it is to read a map, a floor plan, or a blueprint. Understanding pictures is a culturally acquired skill. There is perspectival convergence in the pictures because that’s how we have learned to interpret pictures.

But if you observe the real world, not pictures, you can, with practice, get back into your natural attitude (non-metacognitive) way of perceiving, and there will be no linear convergence. Try it. Walk some hotel hallways and some grocery aisles and some railroad tracks. What do you really see? You will find that the sides do not close in on you. You do not really see linear convergence unless you imagine you are "looking at a scene" instead of being in the world. We CAN take an attitude of detachment toward our perceptual experience, but that is a learned, introspective skill.

It seems to me it would not be too hard to test this hypothesis experimentally, with infants and non-human animals. You could test them for discrimination of natural scenes with and without perspective elements (what most people would call perspective elements, like railroad tracks and hallways). My hypothesis is that there would be no discrimination between scenes conventionally interpreted as containing convergence, and those without. It would be hard to do this without pictures, but not impossible. I notice recently that some hotels go to great lengths to break up the perspective effect in their hallways by using alcoves, varied lighting and wall colors, and non-linear carpet patterns. It should be possible to find comparable but contrasting hallways.

Then you could train the animals or infants to discriminate comparable perspective and non-perspective drawings, then test them on the natural scenes again. If the training were effective, the post-test should show discrimination of scenes with convergent and non-convergent elements. However, It might be difficult to accomplish the pictorial training, as the skill takes a long time to acquire.

Who Cares?
Why does it matter whether we really see linear perspective in the world or just apply that cultural interpretation to what we see? I think it matters for two reasons.

1. It matters if we are seeing the world wrongly. We know the train tracks do not converge in reality but we see that they do. That’s wrong, a perceptual error. Well, if we see the world wrongly in that case, what else are we seeing wrong? What if it's all wrong? Is the world anything like what we think it is?

This is a fundamental question in the philosophy of perception. So-called “realists” believe that we see what is really out there. Sure we make errors, but over time, we generally understand what the world is really like.

On the other hand, “representationalists” say that our brain forms a neurological representation of the world and that is all we have to go on. We do not know anything for sure about the world in-itself. We know only what our brain represents for us, and that includes convergence lines of perspective.

I am a realist, and I have argued endlessly with representationalists about this. Representationalists tend to be interested in robotics and machines that can “represent” the world in computer memory. Representationalists use the illusion of linear perspective to argue, “It looks like the train tracks converge, but they don’t really. Therefore realism in perception is simply not true.”

My argument now is, “I deny that it looks like the train tracks converge. That is a learned attitude, an introspection, not natural perception.”



2. The second reason the perspective illusion matters is because it highlights a fundamental error people make about visual perception. The eye is not like a camera and does not work like a camera. Yes, the eye has a lens and a pupil (shutter opening) and the retina is analogous to a film. But the analogy is flawed and deeply misleading because an eye is a component of an active sensory system in an exploratory animal. A camera is an inert machine.

We do not look at our retinas, ever. The retinal image is nothing like the image on a film, and nobody ever sees it. A camera is passive, but vision is active, exploratory, selective, and cognitive. Recent developments in sensory substitution amply demonstrate how "mental" perception is (e.g., blind people learn to “see” from video signals translated into vibrations, sounds, pin pricks on their backs, or electrical signals to the brain).

Once you shake free of the erroneous camera analogy, you are free to see the world in your natural attitude, not through an arbitrary cultural lens.

Are the seats smaller in the back of this train?

Outlaw the Magnifying Glass!

How does a magnifying glass magnify? What is its secret? I looked into this recently and was amazed to discover that it works by playing on the human delusion that the world is just as it appears. A magnifying glass leads to a dangerous mind-game!

When you want to look at something very small, you have to move your eye closer to it, but there is a limit to that strategy. You can move a sheet of paper closer to your eyes but at some point it is too close for you to focus the lens of your eye on anything. For ordinary newsprint that distance is about 10 inches for me. Closer than that and the print is just a blur. The lens of the eye has a variable focal length, but it has limits.

Incoming light rays are bent by the lens at the top and the bottom, but pass straight through the middle. That’s how a lens works. The resulting image on the back of the eyeball is upside down, but we are so used to that, we don’t even notice it and we see the world as right-side-up.

To get a better look at a small object, we insert a magnifying lens between the eye and the object.






The magnifying glass is held close to the small object, so in the drawing above, the light rays from the object are diverging outward, so much so that an eyeball placed that close couldn’t bend them down to the scale of the retina (couldn't focus them).

The lens of the magnifying glass bends the rays of light just enough so they fit into the lens of the eye, which can take it from there and focus the object. You can move the magnifying glass back and forth until you find that good distance.

So now your eye can focus the object but why does that make the object seem bigger (magnified?). That’s where the mental delusion comes in. As far as the eye is concerned, if light rays come in at that angle, at that distance, they must be coming from a much larger object. The dashed lines show what the eye “assumes” about those light rays and where they came from.

The eyeball is not very smart and does not understand the optics of a magnifying glass. It only knows, from its whole life of experience, that when light rays come in at that angle, at that distance, the object is large. That is the message it sends back to the brain.

Consequently, when using the magnifying glass, we see the object as much larger than it really is, out of “eyeball habit.” THERE IS NO LARGE OBJECT out there. We see a magnified large object that does not exist! The actual object is the same size it always was. But by tricking the eye, we delude ourselves into seeing an imaginary larger object.

The larger, magnified object is utter fantasy, but we don’t interpret it that way. We implicitly assume that we are looking right at an actual object that just happens to be enlarged. As if objects in the world could really be enlarged on demand!

That’s not how the world works. Things are the size they are. They do not get larger because we wish them to. So why do we accept without worry that we have just magically enlarged an object? A magnifying glass promotes an incredible delusion!

Magnifying glasses should be regulated by the government. We cannot allow children to use magnifying glasses! A magnifying glass is far more dangerous in distorting the mind than any hallucinatory drug.

What is Laughter?

Laughter seems to involve a spasm of the diaphragm, but so does a hiccup, and laughter is not a hiccup. Both are involuntary, but that’s not much help.

Laughter has a stimulus, some visual or semantic event, even if only a memory, that triggers it. You don’t break out in laughter for “no reason.” Something makes you laugh.

Incongruity Hypothesis
Usually the triggering input is something unexpected, out of context, incongruous. Man slips on banana peel and falls. Ha-ha. That’s not supposed to happen. The context shift need only be very slight as with a pun, or a small reversal of semantic or attentional figure and ground, as in a riddle. A violation of expectations is funny. Sometimes.

At other times, violation of expectation is infuriating, as when a vending machine keeps your money and gives you no product. Not funny. Unless it happens to somebody else, perhaps. Violation of expectation can also provoke fear, even terror. So the incongruity hypothesis needs qualifications.

People laugh and giggle after smoking marijuana, possibly because the cognitive changes from smoking result in much relaxed expectations due to limited short term memory and short attention span. Under those conditions, it doesn’t take much to violate what few expectations are left.

Similarly perhaps, I am susceptible to fits of uncontrollable laughter when I am extremely tired. Again, there is a factor of diminution of cognitive faculties that accompanies extreme fatigue.

Tickling may produce laughter because of the incongruity of having your body stimulated in an unexpected way. The incongruity hypothesis is not an easy fit there, but it could be made to work.

Are clowns funny? They are for many children because they violate expectations of what is normal, both in the way they look and the way they act. But many children are afraid of clowns, so the violation of expectation hypothesis can only take us so far. Perhaps it must be a mild violation of context, or at least, one perceived as harmless. So safety seems to be a factor correlated with the incongruity hypothesis.

We laugh when something is funny, but for the most part, what's funny is culturally defined as whatever makes you laugh. Circular though that argument is, it suggests for the incongruity hypothesis that expectancies are culturally defined.

One group’s sacred ritual is another group’s comic farce. It all depends on what you expect and don’t expect in the normal course of things.

There are numerous physiological correlates to laughter in the brain, but that doesn’t tell us much, since we don’t know if they are causes or effects, or some mixture of both.

Likewise, laughter results in numerous changes in the body, but that doesn’t help us understand what laughter is or what causes it. Laughter can lead to tears, but that doesn’t make it the same as crying.

Social Hypothesis
Another hypothesis is that laughter is a social phenomenon, possibly a form of communication. Why can’t you tickle yourself? Maybe because that is uncommunicative. It takes two to laugh.

Of course you can laugh when you are all alone, but according to the social hypothesis, it’s when you are remembering a social situation that makes you laugh.

Laughter is often contagious, additional evidence for its being a social, rather than strictly an individual phenomenon, and more reason to think that it serves specifically a communicative function. What is the communicative message? I don’t think it’s necessarily a conceptualized, linguistic proposition. It seems more like an implicit social understanding, like “We are together now.”

Temperament
Despite the social hypothesis, a third component of laughter seems to be individual mood and temperament. I've met plenty of people I thought were humorless, yet everyone believes they have "a good sense of humor." I’ve never heard anyone say they have no sense of humor. Yet the plain fact is that some people are just not easily amused, while others can find almost anything funny. Humorless people perhaps feel under threat to the self, and if they are never safe, violations of expectations are fearful rather than funny.

Embarrassed laughter supports that hypothesis. Embarrassment arises from a violation of expectation, and can also produce laughter, if the personal threat is not too great. Phony laughter can pretend that the threat to self was insignificant, even when it wasn't.

Conversely, we might expect that people who are self-assured would have a more finely tuned sense of humor, meaning, they would laugh more readily at a wider range of incongruities. This could be tested experimentally, and probably has been.

I don’t think laughter is an emotion. And I don’t think emotions produce laughter, although laughter can produce happiness. We might try to make a grumpy person laugh just in order to elevate their mood. But the laughter is not the mood.

Any temperamental factor would be confounded with socialization, so there’s no way to get a clear picture of it.

Darwin
Charles Darwin, in his fascinating book on the Expression of Emotions in Man and Animals (1898) Made the connection between laughter and aggression. We notice that laughter almost invariably involves showing teeth. Darwin surmised that it might be because laughter is similar to a self-defensive display of aggression.

I don't care for evolutionary "just-so" stories like that, but the conjecture is at least consistent with some of the other ideas I have put forward. If the perceived incongruity is felt to be threatening to the animal or person's self, then one natural response would be self-defense, and one way to demonstrate that is by showing teeth. It doesn't ring completely true to me, being based only on superficial observation of facial expression and not phenomenological analysis, but it is not unreasonable.

Individual Differences
There is another idiosyncratic factor about what makes a person laugh, and it may be different from temperament. Perhaps it is socialization history. Often it is surprising what will make a person laugh.

For example, my wife, a well-educated, articulate, and thoughtful person, loves slapstick physical humor. When she sees somebody walk into a door and bang their head, in a comedic context, she might laugh until tears come to her eyes. Her laughter makes me laugh, but I look at her with bewilderment. Who is this person that thinks a bump on the head is so funny? It’s unfathomable.

For myself, I am partial to linguistic jokes. I love badly formed, ambiguous newspaper headlines, for example, clever captions to cartoons and sly puns. I also enjoy well-observed satire, which relies on good phenomenology. People bumping heads is just not funny for me.
I don’t think those kinds of differences are merely temperamental, but it is difficult to say what could account for them, other than, vaguely, “socialization.”

Animals
Do animals laugh? Many animals make noises, show emotional expression, and vocalize in situations that suggest to us that they are laughing. Chimpanzees especially seem to laugh and they have the cognitive capacity to understand when an expectation is violated. I have read that it is possible to tickle a rat and make it emit a special noise that can be heard with instruments. Is that laughter?

We can’t know if animals laugh because we lack sufficiently detailed intersubjectivity to understand their minds as well as we do with each other. I can be pretty sure when you are laughing because we are the same kind of animal and we know each other’s minds. Speculation about whether animals laugh is best put aside until we understand better what human laughter is.

What is Laugher?
One memorable account of the origin of laughter came from an eight year old boy. When I asked where laughter comes from, he said, "From God. Or maybe from my butt." The first answer says, “Laughter is a part of me that does not originate with me.” The second answer expresses the sudden, involuntary, and inexplicable quality of laughter.

Do Robins Have a Self-Concept?

A fat robin landed on the ornamental pine tree in a corner right out side my study window and looked around. I knew what he was thinking: This seems like a good place for a nest.

But before long he noticed his own reflection in the window, and thinking it was a rival bird, started attacking the window. He flew vigorously up against it and pecked, only to be bounced away by that formidable adversary.

This tells me that robins do not recognize themselves in a mirror. And I’m not surprised. All robins look about the same to me. Of course, they probably think that about us.

The ability to recognize yourself in a mirror is considered an index of self-awareness. Children acquire the ability at around 18 months old. A small red spot of makeup is surreptitiously put on the child’s forehead, then the child is brought to a mirror. Children younger than 18 months do not seem to recognize the mirror image as themselves. However after 18 months they notice the red spot and touch it, or try to wipe it off, and often show signs of embarrassment, such as smiling and laughing.

Presumably, you must have a certain degree of self-awareness to recognize yourself in a mirror image. Children over 18 months pass the mirror test, and so do chimpanzees and dolphins, and even elephants. (See http://notexactlyrocketscience.wordpress.com/2006/11/27/elephants-can-recognise-themselves-in-a-mirror/ for an interesting report on elephants passing the mirror test of self-awareness).

Anyway, robins do not pass the mirror test, and that's too bad. I have had trouble before with robins attacking my windows. They just won’t give up. The window becomes all glopped up with dirt, oils, and bird poop as they maintain their attack for days on end.

So I got up from my desk and walked over to the window, about 12 inches from the tree branch. The robin immediately flew away. The window must not form a perfect mirror if he can see me, a major predator, through the glass. Fine.

But in two minutes he was baaaack! He sat on the branch for a minute, then started attacking his illusory competitor in the window. Again I got up and went to the window and again he flew away.

Two minutes later, he was back again and I scared him away again. This cycle was repeated five times. I wondered how long it would take for him to learn that this was NOT a good place for a nest. I wasn’t really prepared to play this game for several days. So I stood at the window and waited, to see if he would return with me standing right there.

Very shortly, he flew back, but saw me and diverted to land on the ground in the shrubbery below the window. He started pecking the ground "nonchalantly" (it seemed to me), moving around at random. Was it a diversionary tactic?

I soon lost sight of him in the brush, but continued to wait and watch. A few seconds later I noticed a remarkable thing, a single, motionless bird’s eye peering at me through a narrow clear channel from the ground, through the brush, to where I was standing.

The robin was watching me! It was eerie. His unblinking eye stared right at me. I could not see the rest of his body. He was hidden, I would say on purpose, and spying on me!

In order for an animal to hide and spy on another animal, it must have some sort of a self-concept. It must have the animal-equivalent of the thought, “I can see him, but he can’t see me.” Of course it would not be a linguistic conceptualization, but it would have to involve some kind of understanding like that. There is no other way to interpret the behavior of “hiding and spying”.

I was shocked that a bird would even know how to do that. Birds fly around in the sky. They are not adapted to peering through narrow openings in the brush, and you wouldn’t think they have much experience in hiding either.

But then I thought, they must have a lot of experience flying through tree branches and so on, so they would have good skills at seeing an opening through dense obstructions. And I guess nests are sort of hidden, so maybe they have the bird-concept of “hiding” also.

Could he really see me? Birds have excellent vision, as demonstrated by eagles and hawks, who can spot a tiny mouse on the ground from hundreds of feet in the air. Birds have pinpoint sharp vision at great distances, even if their field of view is narrow, like tunnel vision.

He watched. I waited. I started to get creeped out. So I suddenly waved my hands rapidly back and forth in front of my face. The robin immediately retreated and flew up and out of the brush. I never saw him again.

That was yesterday, but I am still unsettled by the experience. I was stalked by a robin! I was not frightened, but made uncomfortable by “le regard,” as Jean-Paul Sartre called it when someone stares at you. I had never considered before that a robin could have enough self-awareness to do something like that.

It seems like we need to discriminate different kinds of self-awareness. The mirror test indicates some kind of bodily self-recognition, but the ability to hide and watch may be an entirely different kind of self-awareness, something less physical and more social than the mirror test defines.

The Phantom Penis

A phantom limb is the feeling that amputees often have that the missing limb is still attached and giving sensations. More than 50% of amputees experience a phantom limb. Phantom breast sensations can likewise occur after mastectomy.

Unfortunately, sensations from a phantom body part are usually painful and that pain is almost impossible to treat, even though the pain is very real, not imaginary.

There is a section of the cerebral cortex of the brain where nerve signals from major body parts go. In a typical drawing of this somatosensory cortex, the amount of cortex dedicated to a particular body part is represented by the relative size of a drawing of that body part. The face, lips, and tongue use a large part of the somatosensory cortex, and that corresponds to our experience that these parts of the body are well-innervated and particularly sensitive, compared, say, to the middle of the back.

There are two of these somatosensory cortexes, one on each side of the brain. The left somatosensory cortex represents the right side of the body, and vice-versa. Normally, if your right hand is stimulated, nerves would fire in the left somatosensory cortex, in the area corresponding to the right hand.

The best explanation for phantom pain is that neurons fire in the relevant area of the somatosensory cortex, causing the sensation in the corresponding body part, whether or not that body part is actually present.

Why would neurons in the somatosensory cortex fire in the absence of the corresponding body part? There is some evidence that nearby areas “take over” the part of the cortex that had been used by the lost body part (Ramachandran, Rogers-Ramachandran & Stewart 1992). The brain acts as if it believed there is no reason to let perfectly good cortex go to waste just because a body part has been amputated. The result can be the experience of a phantom limb and its phantom pain.

In an interesting new study, Ramachandran and McGeoch (2008) surveyed a sample of transgender individuals (also called transsexuals), people who have chosen to change from one sex to the other through use of hormones and surgery. About one out of 2500 males underwent transsexual surgery in the U.S. in the last four decades (Conway, 2002). If you count those men who experience “intense gender dysphoria” (unhappiness with their anatomical gender and desire to be the other gender), but who have not undergone surgery, the frequency is one out of 500. So while uncommon, this is by no means a rare situation.

Ramachandran and MGeoch sampled both male to female (MtF) and female to male (FtM) transgender cases. They asked these individuals if they have ever experienced a phantom penis or phantom breasts. They discovered:

1. Among 29 FtM individuals 62% reported a vivid phantom penis, including phantom erections. Many said they had experienced these phantoms for years, well before the transgender program of hormone therapy. These are people who were born female, so finding such a large incidence of phantom penis sensations in people who had never in their lives had a penis, is remarkable to say the least.

For comparison, the authors interviewed a sample of ten college-aged females who were not transgendered, and none of them reported ever having anything like phantom penis sensations.

The implication is that for some reason the transgender females had the representation of a male’s body in their somatosensory cortex, giving them phantom penis sensations. Ordinary females have a female body represented in their cortex so they would not have phantom penis experiences.

2. Three of the 29 FtMs had postoperative phantom breast sensations. The breasts are typically removed as part of the transgender process. In the general population of women, 33% experience phantom breast sensations after mastectomy.

Why do the FtMs have such a low rate of phantom breast (only 10%), while in the general population it is 33%? The implication is that fewer transgender FtMs have breasts represented in their somatosensory cortex to begin with, so when the breasts are removed, there are no phantoms.

3. Among MtF transgender subjects, 30% experienced a phantom penis after penectomy. Based on published studies of penectomy, such as for malignancy, in the general population, 58% of men experience a phantom penis after the organ is removed.

Why would only 30% of men experience a phantom penis in the MtF group? Presumably, that group includes more men who did not have a penis represented in their somatosensory cortex in the first place, so when the organ was removed, they did not experience a phantom.

Taken together, these findings suggest that a person’s body concept and gender identity are strongly influenced by the neurological mapping of the somatosensory cortex. In the case of transgender individuals, it looks like the brain representation may have a stronger influence than even a lifetime of gender socialization and personal experience living in that body.

Regardless of the plain facts of their bodies and the advice of their social community, transgender individuals undergo enormous anxiety, trauma, risk and expense to get their body morphology lined up with their brain circuits.

This research seems to support the notion that when it comes to gender identity, anatomy is destiny – brain anatomy, not sexual morphology. And it seemingly refutes the idea that gender identity is merely a learned set of social attitudes and behaviors, as some philosophers have argued (e.g., Butler, 1990, 1993).

References:
Butler, J. (1990). Gender Trouble: Feminism and the Subversion of Identity. New York: Routledge.

Butler, J. (1993). Bodies that Matter: On the Discursive Limits of 'Sex'. New York: Routledge.

Conway. L. (2002). How Frequently Does Transsexualism Occur? Retrieved from http://ai.eecs.umich.edu/people/conway/TS/TSprevalence.html on March 5, 2008.

Ramachandran, V.S., & McGeoch, P. D. (2008). Phantom penises in transsexuals: evidence of an innate gender-specific body image in the brain. Journal of Consciousness Studies, 15 (1), 5-16.

Ramachandran, V. S.; D. C. Rogers-Ramachandran & M. Stewart (1992), "Perceptual correlates of massive cortical reorganization.", Science (no. 258(5085)): 1159-1160

Achilles’ Choice: Another Way of Being

In the Illiad, the great warrior Achilles is publicly insulted by the Greek commander, Agamemnon, so Achilles goes to his room in a sulk and refuses to fight. When the Trojans then drive the Greek army to the sea, Achilles gloats with childish satisfaction.

Agamemnon realizes his mistake and entreats Achilles to come back and fight with the Greek army. Achilles relents and the Trojans are pushed back and defeated, almost single-handedly by Achilles.

An interesting part of the story is that before returning to battle, Achilles consults with the gods (actually, his mother, who was a god or a half-god), and he learns that if he fights, he will die in battle. Despite that prophesy (which eventually is fulfilled), he decides to go. Why?

His reasoning is that battle is an opportunity for him to achieve glory and thus immortality. If he stays home, he will live a long, comfortable life, but always in the shadow of his snub by Agamemnon. He would prefer death and the immortality his great deeds will bestow upon his name. And he was right, for here we are talking about him 3,000 years later.

Whether Achilles actually existed doesn’t matter. We are considering this psychological choice, either made by the real Achilles, or by Homer or whoever wrote the story.

It is not a choice I would make, and I daresay, few Westerners would make today. Achilles was not duty-bound to fight. He was a free agent, not under any legal or moral contract to return to battle. Let’s assume there was no compulsion of duty.

Humans seek the esteem of other humans. The psychoanalytic explanation is that we desire to displace our parents as the authoritarian arbiters of life’s meaning. A famous person seems to have transcended individuality, as bigger-than-life parents did, while we are the still-egocentric children.

But what are the rewards of fame if it costs you your life? Achilles knows that even if he is victorious in battle, he will be killed. He will achieve legendary, god-like omnipotence among his people and the immortality of his name, although he won’t be around to enjoy any of it. How is that a good deal?

Achilles' choice is sober: posthumous glory over life. That choice only makes sense if Achilles identifies himself fundamentally as Greek and only secondarily as Achilles. He fully expects to live on because his community will live on, and he is one with his community. The death of the man, Achilles will be trivial, because what matters is the adulation of the crowd, and he will be there among them, because Greek is who he is. That is not mere imagination of future adulation, it is certainty of fact.

I don’t think we have that feeling today, at least I don’t. Maybe some politicians or super-patriots do. For most of us, it is every man for his or her self, so to speak. We will give our lives for duty and honor, but that is about integrity of self-definition, not everlasting glory. We will sacrifice our life for our children, but that is our gift to them, not a personal grab at immortality. A hero will face death to save a community, and there we see the hero’s self-identification with the community, required of a genuine hero, but even there, I think that a non-pathological hero acts out of sense of community, not for the lure of personal aggrandizement.

Achilles was a different bird. He explicitly sought personal glory. When the Trojans were driving the Greeks to the sea, he gloated, “See, Agamemnon? You are nothing without me!” Achilles’ petulance expresses selfish aggrandizement. His later decision to go into battle perpetuates that theme, for he can by pushing back the Trojans, demonstrate to everyone how wrong Agamemnon had been. He will trump Agamemnon’s snub by delivering to him an even greater humiliation.

Yet when Achilles learns that he will die in battle, he decides to go anyway, motivated by the prospect of posthumous immortal glory, not personal revenge upon Agamemnon. That is a different motive that reflects Achilles’ transcendence of egocentric individuality and self-identification with his people.

As if to emphasize this second, mature motive, the Illiad provides us with a mirror image in Hector, the Trojan general. Hector’s wife begs him to stay inside the city walls. ButHector determines, much as Achilles did, that he could not live with himself if he failed to rise to the occasion. His honor was worth more than his life.

We moderns can more easily understand the psychology of Hector’s decision. “Death before dishonor” is a modern slogan. If one’s sense of self is deeply dependent upon the esteem of one’s peers, then dishonor is a far more painful death than any manner of physical demise. The choice is not perplexing.

But Achilles was already dishonored, already dead, psychologically speaking. Was his plan to rise from the dead, re-establish his honor, then return to the dead? I don’t think so. I am sure his plan was to transform his being from the individual personality of Achilles, to the ego-transcendent condition of being diffused into the Greek people admiring Achilles. He would transcend himself not by rising to become one of the gods, which would be hubris, but by dissolving back into the community that produced and sustained him. He wanted to be among the adorers, worshipping a god that he knew personally, the legend of Achilles.

The legend of Achilles won’t literally be him, because personally, he is disgraced, the most humble of persons. Rather, his immortal name will become his higher self, the far side of his mortal humanity. That’s the self he chooses.

In humanistic modernity, normal people don’t work that way. We might seek our inner divinity and strive to become that. But we do not strive to project our divinity outward as a self-object to be admired and worshipped from the point of view of our humanity. Yet that’s what Achilles did. That’s a very different psychology from ours, and we are lucky to have the Illiad still around so we can consider that difference.

In modern times, if a person construes life, self, and world as Achilles did, he is considered mentally abnormal. Consider Seung-Hui Cho, the young man who slaughtered 32 people at Virginia Tech University in 2007. Didn't he follow exactly Achilles' psychological template? We might say that Cho was not acting heroically on behalf of the community, yet in his own mind, he was. He slaughters the nameless others who dared ignore him, honoring his imagined community of like-minded peers. Cho is formally and unambiguously declared mentally ill, which is to say that we do not concur with his construal of the social world.

Was Achilles mentally ill? He acted the same way as Cho, but values have changed. Cho, and other mass murderers like him are therefore guilty above all, of anachronism.

Detecting Zombies

Only philosophers worry about zombies. The “philosophical zombie” is a thought experiment. Imagine a hypothetical being like ourselves in every possible observable way except one. The one thing a philosophical zombie lacks is a mind. If the zombie’s behavior and language performance were no different than what we would expect from a real person, how on earth could we possibly ever tell the difference between a real person with a mind, and a zombie devoid of inner experience? We couldn’t.

It is fortunate that zombies in the movies always stagger with outstretched arms and blood on their mouths, because that helps us identify them as zombies. If they behaved more normally (as in the recent movie, “Fido,” for example, or in the original “Invasion of the Body Snatchers”), we would begin to have difficulty discriminating them from real people. If a zombie acted completely normal, how would we know it had no mind?

The puzzle of the philosophical zombie may seem silly at first, but when you think about it more, you realize it is really just a way to pose a more urgent question: How do we know that any other person has a mind? I only know my own mind; nobody else’s.

As a practical matter each of us assumes that other people have a mind roughly comparable to our own. This assumption is confirmed by observing that other people’s behavior and verbal output is for the most part as expected. But oddly enough, we don’t actually know if anyone else has a mind.

It is an odd quirk of nature that each of us has access to only our own mind. It could have been otherwise. I can see your body. I can hear your words. I can watch your behavior. Why can’t I perceive your mind? Why couldn’t evolution have proceeded down that path? That would seem to be a better choice for a social animal like us. As it is, you could be a zombie, a perfect one, a philosophical zombie with no inner experience, and I would never know as long as you acted appropriately.

The same issue underlies a basic problem of artificial intelligence. It seems only a matter of time until robots become so sophisticated that they act and speak normally. When that happens, they will be functional philosophical zombies.

As long as a robot has a metal skin, and blinking lights on its head we will not be too worried. But as soon as such a robot is dressed up in a convincing artificial skin and a good suit of clothes, it will be come a perfect philosophical zombie. We will not be able to deny that it has a mind and a full complement of inner experiences and feelings like us, because we aren’t even sure about each other! If I deny the robot has a mind, why wouldn’t I also deny that you have a mind?

This puzzle of “other minds” bothered me for a number of years, but no longer. I now believe it arises from a faulty assumption, the assumption that our minds are private. They’re not, at least not completely. They are inherently social. Even introspection is social because it is a kind of thinking, and thinking is social. Thinking is social because language is social. Language is a social invention, arising out of human interaction.

Language does not grow on trees. It is a product of people interacting with each other. You must acquire language from another person, through explicit teaching and learning. If you don’t get the training (as feral children often don’t), language does not develop spontaneously. There is no pill you can take, no exercise you can do on your own to acquire language. It is uniquely a social phenomenon.

To the extent that thinking involves language, and introspection involves thinking, it is clear that introspection is fundamentally a social phenomenon, imbued to its core with the values and assumptions embedded in the individual’s community. Therefore, because I speak and understand the same language as you, I do in fact know what is in your mind (more or less) and I know how you think about things (in general), and most importantly, I know you are “in there,” and not a zombie.

With only a little difficulty, we can make a similar argument about visual imagery and other explicit mental representations of sensory experience and expression, like songs, and so on. They are all social conventions, taught and learned.

What about a robot programmed to have completely appropriate language? Could I discriminate it from a real person? That question constitutes the famous “Turing test” proposed by Alan Turing in 1950. In that test, you have a conversation with a robot and a person hidden from you by curtains, and if you cannot tell which is which, the robot passes the test. In that case, you must, to avoid inconsistency, admit that it has a mind, albeit an artificial one.

Some robots have already passed a limited version of the Turing test, fooling adults, children, experts, psychologists, and many others (http://www.loebner.net/Prizef/loebner-prize.html . While these tests have been limited in scope, are we justified to expect a future robot that qualifies as a perfect linguistic zombie? I think not.

The robot contains the language knowledge of the programmer. In that sense the robot is not a natural language user. It did not acquire its language through the normal course of socialization, which takes many years of daily social interaction. The robot has no family, no peers, no social network out of which language understanding grows. The programmer has all those social connections and is a natural language user. The robot becomes a repository of the programmer’s lexicon and grammar, but not of the programmer’s social history. Consequently, it is not possible in principle for the robot to ever be a perfect linguistic zombie, because genuine language usage and understanding arise from living in a community. That’s why a linguistic robot language will inevitably be identified in an unconstrained Turing test.

Well then, couldn’t a robot be made that does live in a community of humans, and does partake of ordinary social interactions, and does acquire language through interaction like a human does? That would work in principle, but nobody has any idea how to make such a robot, because we don’t even know exactly how the process works for a human being. So in the end, there is no fear of zombie robots.

But more importantly, we can rest assured that if there are any “pod people” among us whose bodies have been snatched, we will know it.

Music and Machine

In listening to Beethoven’s piano sonatas, it occurred to me why his rhythmic patterns seem so different from those of today’s music. He was not surrounded by machinery as we are. The sonatas span 1795 to 1822. The Watt steam engine wasn’t even patented until 1769 and did not become commonplace until much later. Railroads were limited to coal mines until the early 1800’s, so he would not have much, if any experience of train sounds. In Beethoven's experience, it would have been relatively rare to hear the regular whumpa-whumpa-whumpa of rotating machinery. There were waterwheels and some farming machines, but these were not ubiquitous, and they did not spin at the tempos we associate with music.

I have read that the emergence of rock and roll music out of blues in the 1950’s was stimulated in no small part by the wide availability of the automobile in America. Most rock music emphasizes 4/4 time with a relentless drum that recalls the internal combustion engine.

Beethoven’s tempos are subtle, variable, and deeply internal to the harmony and melody. When his rhythmic structure does become obviously regular, it usually sounds like a march, a waltz, or some other human movement, like a person spinning, or like something falling down a slope. From what does the regular arpeggio of the Moonlight Sonata derive? To me it sounds like the movement of a human body, swaying or tapping. It does not suggest any kind of mechanical action like that of an engine.

Music experts always tell us that musical elements refer only to themselves, not to anything in the world, but I have never found that argument convincing. There are, after all many “pastoral” musical forms, madrigals, and other types designed explicitly to be representational. I don’t say that all music is symbolic, but musical ideas have to come from somewhere, and where else but the composer’s experience could they come?

That’s why I think Beethoven’s sound is so organic, compared to modern music. The musical ideas are intimately from the natural world, deriving from wind and waves, footsteps and horse hooves, dances, songs and screams. Just about all pre-modern music would be that way. You never get a sense of machinery. There is something almost suffocating about Beethoven’s music just because it does immerse you in the sounds of life.

Maybe that’s why classical music is considered “difficult” for most people. Anyone would understand more easily music that reflects the soundscape of their everyday experience and for us, that is a mechanized world. Our machinery keeps us distant from the natural world. We drive in our car out to the country to visit nature. We don’t live in nature anymore and our mechanically inspired music reminds us of that.

Beethoven’s is an ambient auditory world that is lost to us, probably forever. (And of course was lost to him as well, in his later years of increasing deafness).

Funniest or Stupidist Joke Ever

I was reading a humor book with all kinds of jokes when one hit my funny bone:

A man goes to a costume party with a woman draped over his shoulders and says he’s come as a tortoise. “Who’s that on your back?” asks the host. “That?” he says, “That’s Susan.”

I visualized the situation and the dialog and laughed so hard I had tears in my eyes. The absurdity of it just blew me away. Even now I am chuckling as I read it again.

So I read the joke to my wife. “That’s more stupid than funny,” she said without smiling. What? How could she not appreciate the surreal insanity of the joke?

I read the joke again and realized I had misunderstood it. The last sentence of the joke actually reads, “That?” he says, “That’s Michelle.”

It always did say Michelle, and that’s what I read the first time, but I did not connect the name to a terrible acoustic pun, “That’s my shell.” In my mind, “Michelle” could have been “Susan” and the joke would have been just as hilarious and that’s how I read it. My wife was right, the joke, as intended, was stupid, not the least bit funny. She had ruined it for me!

But if I ignored the acoustic pun and read the joke again as I had originally, it again became so funny I could not stop laughing for several minutes.

What was going on here? If the last line had been:

“That’s my dog.” Not funny.
“That’s just some woman.” Not funny.
“I don’t know.” Slightly funny.
“That’s my wife.” Slightly funny.
“That’s a corpse.” Not funny.
“That’s a Martian.” Not funny.
“That’s my collar.” Not funny.

What is it about “That’s Michelle/Susan” that makes the joke so funny the way I read it?

I was set up for a tortoise joke, and in the special syntax of jokes, you expect the punch line to involve some distinctive feature of tortoises, such as the fact that they move very slowly, or are hemispherical in shape.

(www.davethompson.org)

That the man had a woman draped over his shoulders is already slightly funny. To say he came as a tortoise is also slightly funny, but the two ideas don’t add up to anything. If the joke had ended there, it would be such a total nonsequitur that I might have thought it was a misprint.

But when the host inquires about the woman on his back, I am led to imagine that there is a mystery to be solved about the costume. The host is thinking, “Okay, tortoise, if you say so, but what part is played by that woman on your back?”

The man answers with a surprised question, “That?”

That’s a nice bit of joke-writing there, because why would he be surprised by the question? If the woman really is part of the tortoise costume, he should be eager to explain the connection, but instead, he acts as if he had forgotten he had a woman on his back. So as the joke reader, I am thinking, well, maybe there is some other explanation here. I have been misdirected.

But the punch line, “That’s Michelle,” implies that she is always there. “Oh her, that’s just Michelle. Don’t pay any attention to her.”

It’s as if the guy is completely accustomed to having Michelle draped over his shoulders. I imagine Michelle being rather slim and drape-able, dressed in a tight, shiny party dress, lying limply over his shoulders with her long hair, arms, and legs dangling toward the floor.

But given the setup about a costume party and him presenting himself as a tortoise, with the forgotten Michelle on his back, the punch line is hilarious because of the juxtaposition of the two speakers’ assumptions.

The host is inquiring about the costume, but the guy answers as if he heard the question as an inquiry about the girl, which he answers matter-of-factly, as if it were a reasonable answer to a simple question.

It is that sudden shift in context that made me laugh. Even after analyzing this to death, I am still chuckling now.

Here’s the same joke in a different form:

A man walks into a bar with a beautiful multicolored bird on his head. “Wow,” the bartender says, “Where did you get that?” “I got him in France,” the bird answers, “They have millions of them there.”

Again the humor arises from the juxtaposition of the two speaker’s differing points of view, each oblivious to the others’. But this version is less funny because the differing contexts of understanding are confounded with the violation of expectation by having a talking bird, and that diminishes the effect of the context shift.

In the original joke, the opposition of the two speakers’ contexts is pure funny. Why, exactly, I still don’t know.