futurehead

Arbortrary judgments

On my daily ride through Arlington National Cemetery the other day there was a big truck parked in the middle of a row of gravestones, with a crane on which were workers taking down a tree.  I looked around at all the trees in the cemetery -- big, beautiful trees, many of them, and as I coasted by Robert E. Lee's old house, I wondered how many of them were standing when he lived there.

The tree the workers were taking down had clearly been given a death sentence by some arborist.  I pictured the Arlington Cemetery staff arborist and how he must keep track of all those trees. That made me wonder how they know when a trees should be taken down.  And, how clear is it for an arborist when a tree needs to be taken down?  If you got 100 arborists and had them look at all the trees in Arlington Cemetery, how consistent would their recommendations be? 

Which raises the question, what about other professional fields?  Of 100 economists, how many would prescribe the same course of action when faced with a situation?  How many podiatrists would diagnose the same problem and prescribe the same solution.

It would be nice if there was a way to create a standardized measurement for this across fields -- an "intra-professional consistency" metric, if you will.  Of 100 specialists, how many reach the same conclusion?  And what is the standard deviation of their responses?  Which fields are the most unified, which the most fragmented?

Clearly, there would be a scale.  How many poets would describe love the same way?  Probably none.  On the other hand, how many physicists would calculate the mass of an object the same way?  Probably all of them.

In addition, intra-professional consistency varies not by profession, but by question. 100 physicists will agree on the mass of an object -- but not on the nature of a quark.  Here we spin off into the land of Thomas Kuhn and the complex questions of the philosophy of science.

That means that it will never really be possible to do this in any kind of genuinely standardized way across professions -- a standardized way of testing could be created *within each field* but not one that permits genuine rigorous comparison between, for example, astronomers and radiologists. 

Really, there are two core questions.  First, what are the questions on which a profession agrees. In physics, the basic questions of mass and motion and newtonian gravity are basically figured out in that the entire field agrees upon certain answers.  But there is much disagreement over the nature of energy.  Each field has its areas of agreement and its unknowns where the experts disagree.

The second question is whether the answers on which a profession does agree are actually correct.  It may be that 100 out of 100 podiatrists would all diagnose a runner with the same problem and prescribe the same arch supports -- and yet all of them could be under the sway of a false historical-cultural understanding of feet and be misguided in their prescription.  Similar errors can be made by any profession including physics.  At the same time, 100 poets describing love are certain to overlap very little in their "solutions" to the problem -- and yet a high number of them are likely to express truth of various kinds.  So, professional consistency does not necessarily correlate with the truth or usefulness of a profession's beliefs.  As I written about, there have always been groups of experts who are completely wrong.

That said, it is a useful analytic concept -- a concept that may not be found in nature but which is nonetheless useful for thinking about things.  I *would* be curious about the degree of consistency of recommendation of various experts on various matters.  It's no guarantee of correctness, but a lack of consistency sure tells you something (what philosophers might call a lack of intersubjectivity).

Economics of course is very low on the consistency meter -- nothing wrong with that, that's to be expected in the humanities; history is the same way. The only problem is that unlike with history and poetry and the like, too many people fail to perceive that economics is, in fact, one of the humanities (a particular, warped form of history, I would argue; others argue it's more like literature).  Instead our culture treats economics as if it were a science.  And that illusion of objectivity has very real damaging political and social effects.

Out of the Teflon, into the iron

One of my favorite purchases in the past several years has been our collection of nice, solid, good, honest, cast-iron frying pans. 

I’ve always been a little suspicious of Teflon and all the other fancy chemical surfaces that all these no-stick pans have on them.  You know these chemicals have just come out of the lab, and can’t possibly have really been tested thoroughly for their effects on human bodies, including the bodies of children, including over the course of many decades (they haven’t even been around that long!), including when inhaled in the form of vapor as happens when the inevitable pan-burning episode strikes.  Once a few years ago we burned such a pan and the whole house had a strange odor.  I also remember the whole family got sick – my memory is not reliable here, I can’t remember the precise timing of when we got sick, when the pan was burned, etc., having only linked the two in retrospect – but it only added to my pall of suspicion over these pans.  I had been using them a tad uneasily for many years – our modern world is one of many risks and many compromises, and you never can achieve purity from contaminants of any kind.  Still, as I get older, I increasingly prefer the kind of contaminants that my great-grandparents dealt with and survived, and their great-grandparents, and so on.  The contaminants that just emerged from the labs over at Dow Chemical or what have you, I’m a lot more uneasy about.  Not to brag, but I am descended from a long line of people who, for thousands of generations and without exception, survived to childbearing age despite, in most cases, living in a sea of excrement and rot and disease.  But that was 100% organic excrement and rot and disease!  Actually, we can all claim such a lineage - it’s called evolution.  Okay, many and often most of their siblings didn’t make it.  And when I say they survived, that means only until childbearing age.  After that, their fates varied widely but tended toward death between ages 30 and 40 – something I assure you I am mindful of, lest I be accused of a post-Sixties romantic, naiive-Rousseauian preference for the state of nature (an accusation to which I am already vulnerable due to my preference for barefooting.  Let me assure you that I am a modernist in many respects).  But still, give me bacteria over the next DDT any day. 

Better Living Through Chemicals Iron

Anyway, the pans.  So, one day I threw out all the Magic Coating stuff and switched to the cast-iron.  They’re great!  Many of the big chefs use them, I have since read, you get a little extra iron in your diet from them, and – get this – in terms of their no-stick quality, most of the time they work just as well as these spooky chemical surfaces.  The secret is, when you wash them, don’t use soap!  You just scrub all the food off them with water, but don’t try to soap away the thin film of oil or grease that is on the pan, it’s totally sanitary.  Gee, people did pretty well with cast iron for a long time before Teflon, don’t you think?  And if you’re cooking something like eggs and worried about the sticking, it’s simple – just cook with lots of butter!  Turns out that margarine (aka pure trans-fats) is another modernist invention that hasn’t worked out so well.  I know it’s been deeply impressed upon all of us that fat is bad and will make us fat and clog our arteries, but there’s good & growing reason to believe that there may be nothing wrong with good dollops of butter with your eggs, as long as you go easy on the carbs.

Right, right – the pans.  The other thing I like is the simplicity, the weight, the solidity, and the classic nature of these big black pans.  I know David Brooks would say it’s all part of the Yuppie quest for authenticity blah blah blah, but combined with the good solid rational reasons for cast-iron, I just love these things.  And I keep expecting them to become an enormous trend and start filling the aisles in Crate & Barrel and Target, because usually whenever you really catch on to something, it soon follows that you discover half the world is right there beside you; but so far no huge trend toward cast-iron that I’ve noticed.  On second thought, when I catch on to things, the world is actually seldom right there with me.  Everyone still wears shoes, for example.  Oh well.  Wait, I know – it must just be because I’m just ahead of my time.  Like when I swore off the car-based lifestyle in 1989 and moved to Manhattan.  Because even then it had long been clear to the attentive liberal that our nation's investment in cars and oil was a doomed world-historic folly.

Anyway, the pans.  They're great.  They are heavy, though.

Poetry vs. prose in athletics (and elsewhere)

I participate in some Internet forums on running, and sometimes there is debate there over proper running form, with some participants resorting to physics and mathematics in order to make their point about the best running form.  I find such analysis to be not helpful in the least.  What *is* helpful is a good mental image.  For example, “run as if you’re running on wet paint” (the point being not to push off the ground with your feet but simply to lift them).  When swimming, “imagine that you are strapped to a backboard as if you’ve been in a car accident” (to keep your body straight in the water).  I find this in many sports – that attempts to actually accurately describe the motions that your body parts should follow, are not nearly as much help in achieving the form that the instructor feels is best, as a good cartoonish mental image.  When it comes to athletics, poetry is better than prose. 

Maybe that’s true more broadly as well.  If we look at the physics of our existence, it looks pretty unglamorous; on a physical level we appear to be nothing more than complex chemical reactions that have come about through some weird mathematical quirk (circular self-sustaining) in the universe.  Take an old philosophical question such as: do we have free will?  If you look at it closely, it’s pretty hard to see how we could.  Everything that is, everything we do is the result of everything that has happened before, in an unbreakable chain of causation (quantum indeterminacy or not!).

We’d all like to believe that we are morally responsible for our actions, in control of our selves.  But how do you explain all the people out there who go insane because they have a screw loose?  Are they morally flawed?  Is schizophrenia the result of bad choices?  C’mon.  Why do people improve when given lithium?  Why do people act crazy when given other drugs, from alcohol to LSD?  If these people do things because of chemicals in their brain, why are the rest of us any different?  We tend to put the extreme examples in a separate category, but why wouldn’t subtler effects be just as chemical in origin?  Why are some people grumpy, and others sweet?  Couldn’t such everyday differences be as much a difference of variations in brain chemistry, as the difference between a schizophrenic and a “well-adjusted” person?  Is a well-adjusted person that way in much the same way my bicycle is well-adjusted?  There is just too much evidence that people are the way they are because of their brain chemistry. 

Sure, experience and environment play a big role in how people are (though much of that, in turn, is stuff that happens to people, rather than anything we could even begin to think people have control over or choices about or free will concerning).  And chemical brain states can reflect, rather than cause, mental states.  But if take a murderer, for example, and try to break down the factors that led to their terrible act, it’s hard to see where “free will” enters the equation.

But on the other hand, who cares?  Like the physics of swimming, the physics of our existence is, at the level at which we live our lives, unhelpful.  The prose, the physics, is philosophy.  But it is poetry – meant broadly – that is the stuff of life:  to be or not to be; the path not taken, how do I love thee?

The problem with poetry, of course, is that it is a lot harder than in physics, to find grounds upon which different people can agree what is good and what is bad, what is true and what is not (though even in physics that ain't so easy as most people think). That just means you have to create your own life, there's no formula.

I’m sure this is a really trite and well-trodden line of thinking, but hey, I’ve just reached it myself, and it's my blog.

Temperature regulation

I've never been one to force my kids to wear coats when they don't want to (though I sometimes force them to bring a coat when I suspect they're going to need it).  It bugs me when teachers or others with temporary responsibility for my kids force them to wear more clothes than they want to.  First of all, there is no reason to engage in power struggles with kids when they are perfectly capable of regulating their own temperatures.

More significantly, however, adults could actually be doing children harm by forcing them to wear more clothes than they want.  Here's why:

1. Children are more tolerant of the cold.

In my observation, many children are naturally more tolerant of cold temperatures than adults.  This despite the fact that their smaller size should render them more susceptible to the cold (because they have a much higher ratio of surface area to volume). 

2. Human beings actually adapt and adjust to different temperatures

First, I have also heard a lot of anecdotal evidence from people moving to colder or hotter climes that they get used to it after a year or two. 

But also, a renowned scientist named Laurence Irving did body temperature regulation experiments at the University of Alaska in the 1960s.  According to this article, Irving

noticed with great curiosity two UAF [University of Alaska Fairbanks] students who walked around campus barefoot, even in winter. In accordance with their religious beliefs, the students wore only light clothing and wore no shoes or socks....

Irving convinced the students to sit for him in a room cooled to about 32 degrees. The students were allowed to wear light clothing, and Irving measured the temperatures of their fingers, toes and chest as they sat for an hour and studied.

For comparison, Irving recruited a "vigorous young airman" to undergo the same test. After 30 minutes, "the airman's toes became so painful and he began to shiver so violently that I caused him to terminate the test lest he shake himself apart," Irving wrote.

The students who walked barefoot on snow every day didn't begin shivering until after almost 50 minutes in the room....  The study was an illustration of how humans can acclimate their bodies to cold weather and eventually feel little pain while walking barefoot in the snow, Irving wrote.

I came across this account through my interest in barefooting, the astute reader will gather, but it has wider implications (according to this article barefooting in Alaska winters is still going on -- though it can't be too common or it wouldn't merit a newspaper article!)

This New York Times article says that people can also adjust to hotter temperatures:

The process is called heat acclimation and is routinely seen in athletes training in hot weather. At first their internal temperatures climb, they sweat profusely, lose large quantities of salt in their sweat and feel miserable. But as the days pass they sweat even more, their salt loss diminishes, both skin and internal temperatures drop, and their endurance improves. . . .

And it took only a week or so for the research subjects in the California desert to develop high sweat rates, low pulse rates and low rectal temperatures. They could work more comfortably, with greatly improved well-being.

3. As a result of these two facts, two conclusions follow:

1. One person's judgment of how cold it is, is not necessarily accurate for another, especially for children.
2. Making kids wear unnecesary layers will just ruin their adaptation to the cold. Aside from being inconvenient, and seeming generally a pity, this could potentially add to a child's risk of obesity since the metabolic changes necessary to tolerate more cold presumably use up more calories.

I say, let children regulate their own temperature! 

All this could also have implications for adults as well: I once heard of a couple who swore that they were able to stay thin by sleeping with only a sheet, never using a blanket. Maybe there was something to that.

Colossal errors

It's always fun when entire bodies of supposed expert knowledge, fundamentals that are accepted by nearly everyone, are revealed to be wrong and/or unfounded.  My attention has been drawn to three strong examples of this phenomenon:

• Low-fat diet
• Shoes
• Economics

Once you internalize the fact that even mighty establishments, possessing the finest acronymed professional societies and mahogany-and-brass lobbies, all of whose members get plenty of respect at their local country clubs, can be totally full of shit, it is both liberating and, in a way, paralyzing.   I posted yesterday about how the Internet is having both of these effects in the medical arena.  And there are plenty of comical examples to be found of how this has been true in the past, with even the most highly and widely respected "experts" (doctors, scientists, philosophers, economists, etc).  Yet it's a lot harder when you are ensconced in *today's* discourses and claims of expertise and received wisdom.  It's like being trapped in amber -- it's a lot harder to assess the quality of the piece than when you're on the outside.

The shattering of received wisdom is liberating because it teaches you to question what other "common sense" might be way off track, and to grasp the contingency of our world -- just how broad the scope of possibilities are.  It could be true that our current understanding of economics is pretty good -- it could also be true that it's totally bogus, and we'd be better off with all kinds of radical changes (I strongly suspect the latter).  It frees you up to be practical and pragmatic, since you are no longer wedded to various notions of Truth, you can just more directly seek practical solutions for what's good policy.

On the other hand, the busting open of possibilities can be paralyzing. The more things in life that are open to question, the harder it can be to know what to do. 

Let's look a little closer at my three examples.

Low-fat diet

For a few decades it has been accepted medical wisdom that a high-fat diet is bad for you.  But the whole low-carb movement started by Atkins has challenged that wisdom, and pointed out that in fact, there really isn't actually any solid evidence that that is true.  They point out that shortly after you eat a bowl full of pasta, your body turns it into what is more or less the equivalent of a Snickers bar.  Even whole grains go through the same process, just a little more slowly.  And if you're not getting your calories from carbs (sugar, more or less), you basically gotta get them from fat.  As I mentioned in a recent post, it may be that it is not true that a calorie is a calorie, because fat calories make you feel fuller, while sugar calories do wacky things to your insulin system and can actually make you feel more hungry.  I notice this myself -- it is after a big pasta meal that I crave dessert the most.

To get a better explanation of this, and a fuller sense for just how wrong the conventional wisdom seems to be, read this excellent summation that ran a few years ago in the New York Times Magazine.

I was intellectually persuaded of the merit of these arguments by this and other pieces.  But (as the author of the piece himself alludes to) it is still hard to eat a high-fat diet without feeling that you are hurting yourself, while you don't feel that way at all eating pasta still.  This shows the power that these kinds of social understandings have over us and our tastes.

Shoes

It's all a big lie, man.  Just like gloves, safety goggles, and helmets, shoes are a useful piece of protective gear in some circumstances -- snow drifts, steel mills, and the like.  But overall, they just aren't that necessary, as a few brave pioneers willing to flout social convention have discovered, and I have confirmed for myself.  If I can run 15 miles on asphalt roads with my soles intact, then just when is it exactly that I need shoes?  As I have gone into, they are more of an irrational cultural holdover from  medievalistic, tribal, hierarchical, aristocratic, status-obsessed European historical cultures than a necessity of life.

Yet our society is pretty twisted when it comes to bare feet.  As barefooters.org points out,

consider a business near a beach. This business has barefooted customers all day long. Not only has nobody ever contracted any sort of illness from somebody else's bare feet, but nobody thinks anything of bare feet because it's "OK" to be barefoot near a beach. Now, transport this same business a few miles inland. Suddenly, without any change to the inside of the business, bare feet are an alleged health risk. Does this make sense?

(By the way, no state has any law prohibiting bare feet in any restaurant or other establishment. Or while driving.)  As the site points out, people don't usually mind flip-flops and sandals where the top of the foot is entirely visible -- it's the fact that someone lacks material on the bottom of their foot that bothers people. Again, what sense does that make?

It would be one thing if this was just a social custom that flouted hard evidence -- hardly an unknown.  But even the experts, as represented by foot doctors quoted in most articles about barefooting, appears to recoil at the idea of going barefoot.  I never see them address the substantial body of evidence that barefooting is far better for your feet.  Granted, it would be a hard sell for most doctors to instruct their patients to go barefoot full time, and a lot of patients would demand other remedies, and go to another doctor if they could not get them from their first.  But the best doctors think like scientists, in the full, rich sense of that term -- rational and evidence-guided, but also imaginative, intuitive, and brave enough to follow that evidence where it may lead.  They're not supposed to be petty-bourgeois shopkeepers, concerned about their customers and their market and their competition.  And they're not supposed to swallow holdover Elizabethan cultural biases and just pass them down to each new generation of doctors.  Even if patients resist the evidence, doctors could advise them to at least go barefoot as much as possible, and some do, but the profession does not seem to do this in general; instead they are actively steering people away from barefooting and toward baroque (if profitable) foot inserts and the like.  I wonder how many doctors have even investigated all the literature that is out there, and weighed it scientifically.

A pretty good article just came out in New York Magazine that also does a decent job of summarizing what's wrong with our conventional wisdom regarding shoes:  "You Walk Wrong: It took 4 million years of evolution to perfect the human foot.  But we're wrecking it with every step we take"

Economics

Oh man, I really hate economics.  I could write a post a day for a year on this subject, if I only had the time.  I will leave most of this subject for future posts, but suffice it to say here that while the field produces many useful and interesting intellectual tools, they never add up to a coherent body of knowledge; the very notion of homo economicus on which the field is based is a total myth; the very idea that a social science can be based upon physics as a role model is a giant anti-historicist error; the history of the field shows little evidence that economics is getting closer to the truth; and the field has an inborn conservative political bias and cultural effect even when practiced by liberals.

As markets implode, venerable companies fall to their knees, vast neighborhoods are reduced to ghost towns, and the national (world?) economy teeters, this is increasingly not a difficult case to make.  Over and again throughout history, economists and the conventional wisdom they impart have been proven to be colossally in error.  Examples include:

• The mercantilists, who viewed the economic arena as a zero-sum battle for power among nation states, and wealth as more important than production
• The Physiocrats, who in the 18th century regarded agriculture as the only basis of wealth.  The industrial revolution kinda showed otherwise
• The Classical Economists, who advocated the hands-off approach that led to and was discredited by the Great Depression
• The Keynesians, who thought they'd figured everything out, until they were discredited by the (supposedly theoretically impossible) combination of high inflation, slow growth and high unemployment ("stagflation") in the early 1970s
• The post-Reagan free marketeers, the cock-sure ideologues of our own era, having explained away the Great Depression and much else, seek to move back towards pure Classical Economics (which never really existed).  While the intellectual descendants of the Keynesians have become more humble epistemologically, the Free Marketeers think they have the Answers, and their viewpoint dominates our culture.  We may be witnessing the wheels come off this latest economic blind alley at this very moment.

Who will be next? 

What these error-ridden subject areas have in common is that:

• They are irredeemably complex -- there are just too many variables to be susceptible to reductionist analysis
• They are heavily burdened by thick cultural baggage
• They result from stunning failures of epistemological humility. I remember asking proponents of Bush's Iraq War before he started it, "where are the nukes?" If Saddam has them, let's see them before we invade -- by which I meant, let's be sure they exist.   Why don't dietitians ask themselves, "where's the evidence a high-fat diet is bad?  Why don't foot doctors recognize just how little we know about sports medicine?  Why don't economists recognize the historical nature of their discipline?

The Internet and Doctors

One of the great things about the Internet is how it has changed being a patient.  If you are at all like me and prone to thorough researching of any medical ailment that hits, you know that the Internet has had big effects on how we relate to our doctors:

• When I go in to see a specialist I am usually quite up to speed on the basics of my condition, the parameters of possibilities for what the diagnosis might be, and how the body part in question functions.  (See this New Yorker cartoon.)
• One problem is how to convey to the doctor how much you know so you don't both waste time.  Some doctors don't want to hear how much you know, because they are afraid it will revealed them as naked of an special insight or expertise.  The best ones quickly jump onto your wavelength and get into the more advanced topics.
• You also often encounter alternate medical theories, which can sow doubt in the doctor standing before you with his conventional outlook. The Internet amplifies dissenting voices, so that conventional wisdom can be more easily knocked off its pedestal. If not digested with a very critical eye, this can easily fill your head up with junk.  You could see how doctors could find that annoying. 
  
• At the same time though, often the conventional wisdom is wrong (and/or unfounded!). Internet research often throws into stark relief just how sharp are the limits of medical knowledge in many areas, which can also lead to a morass of ambiguity and doubt.  The dirty secret of medicine is that a huge amount of what doctors are running around telling people is not actually based on research.  When you lose faith in doctors, you lose the comfort of having a confident person in a white coat who knows all the answers tell you what your problem is and exactly what to do. I find that I have a lot less patience now for Voice of God doctors who can't handle being knocked out of the role of infallible expert.  Often when I see a specialist what I'm looking for is a consultant, who can reality-check and narrow my own self-diagnosis.  Someone who is secure enough to be upfront about what she knows and doesn't know.  I know too much to be comforted by the white-coat role, it's just annoying.
• But the Internet also collapses statistical differences.  What I mean is that there may be a symptom you have, and one possible cause is something benign, while another cause is some devastating horrible fatal disease.  Your doctor knows that he sees people 4 times a week complaining of that symptom, and only once every few years is it caused by the fatal disease.  But online you rarely get that "feel for frequency," which is one of the things a real live doctor can get you.  The fatal disease might loom nearly as large in the online discourse as the everyday cause, and even though you may read that the symptom is "usually the result" of the benign condition, that message gets contradicted by what you read. 
• Another irreplaceable thing live doctors offer is not just a feel for frequency, but also the ability to feel, period -- to assess the nature of a lump or some part of your innards and through their experience and their feel for things, determine things about your condition.  This is what Michael Polanyi called "tacit knowledge", and you can't put that on the Internet. 

You can outrun most animals

You may think that as a human being you're a poor runner compared to most animals, but it turns out that we are actually some of the best runners in the animal kingdom.  You can outrun most animals -- as long as the distance is long enough.  We suck as sprinters, losing out to every squirrel and rodent -- but, according to this fascinating and persuasive (at least to this layman) article in Nature, "Endurance running and the evolution of Homo" (pdf), "humans perform remarkably well at endurance running," and running "may have been instrumental in the evolution of the human body form."

Sometimes non-triathlete friends make cracks about how my "extreme" training is sick and contrary to nature.  But if this article is to be believed, it's actually entirely "natural" for humans to run very long distances.  The authors, biologists Dennis M. Bramble and Daniel E. Lieberman, cite a variety of arguments, including a bunch of physiological and anthropological gibberish I can't follow but also these facts:

• Humans are the only primate that is capable of endurance running (ER).
• Actually few animals can even do endurance running, except for social carnivores like dogs and "migratory ungulates" like horses. (By the way, as carnivores, you have to wonder how dogs do well in endurance running without a lot of carbs?  More evidence that you don't need a high-carb diet to perform). 
• Speed: "Sustainable ER speeds of humans are surprisingly comparable to specialized mammalian cursors [ie runners] such as dogs and horses....  When galloping, species with high sustainable speeds such as dogs or horses can usually outrun humans....  However, human ER speeds are quite comparable to the preferred galloping speeds that cursors use over longer distances and times."
• Despite our primate ancestry, we somehow evolved to run distances roughly comparable to the longest distances dogs and horses can run. 
• Compared to apes, human legs contain many long, spring-like tendons that function as economical springs for storing and releasing energy as we run (but do not help much in walking). One of the most significant is the Achilles tendon.
• "Another well-developed set of springs important to human running is the longitudinal arch of the foot....  during running, the elastic structures of the plantar arch function as a spring, returning approximately 17% of the energy generated during each stance phase."  (Pity all those people who run in shoes, huh?  They're really losing out!)
• Humans have long legs relative to our body mass compared to many other animals, and it seems to many of our evolutionary ancestors.
• Since our legs are pendulums, the lighter the lower ends of our feet are, the less energy it takes to swing them.  Compared to other primates and to our fossilized ancestors, our feet are a lower proportion of total leg mass (again shoes have got to hurt here), and we resemble dogs and horses in having compact feet and short toes.
• Compared to our fossilized ancestors, humans have large surface areas in their lower (but not upper) joints, which dissipates skeletal impact forces from running.
• Compared to other primates, humans have a "greatly enlarged" gluteus maximus (aka, butt).  "The latter muscle, whose increased size is among the most distinctive of all human features, is strongly recruited in running at all speeds but not in walking."
• We also have overgrown "spinal extensor muscles that contract strongly to stabilize the trunk in running but not walking; and an elongate, narrow waist in combination with a low, wide, decoupled shoulder girdle that have an essential stabilizing function only in running."
• The "elevated shoulders and strong muscular connections to the head and neck" shared by other primates and our own evolutionary ancestors are "functionally advantageous for climbing" and don't hinder walking, but interfere with the body stabilization necessary to run on two feet.
• "The wide shoulders characteristic of Homo act to increase the counterbalancing moments generated by arm-swinging, while also permitting energy-saving reductions in forearm mass." The human forearm is 50% smaller relative to total body mass in humans than chimpanzees, which makes it a lot easier to swing our arms while running.  You'd think the stronger arms would be an evolutionary advantage for our ancestors.
• Heat dissipation: "elaboration and multiplication" of sweat glands, and reduced body hair.
• "The tendency for mouth breathing (but not panting) during strenuous activity."  Apes are typically nasal breathers.

The authors conclude with some interesting speculations on why humans may have evolved as runners, such as persistence hunting -- ie, running your prey into the ground.  (Kind of like what some of my friends do to me when we run together.)  Some native peoples like the Tarahumara of Mexico still do this.

I may still say to myself near the end of a hard run or triathlon, "what the hell are you doing this for?"  But at least I won't have to wonder whether I'm doing something freakish and unnatural.  Born to run, baby!

The bubbled and the unbubbled

In the movie Gattaca, the premise is a future world in which humanity has been divided into two classes, the genetically engineered (the superior class) and those who are “natural.”   The plot has to do with a Natural trying to pass as one of the engineered people. 

I was thinking recently that another kind of dark future division may be just as likely. 

Throughout the history of our species (and before), we have lived in a sea of microbes, and our biology reflects that – from the microbes that live in great numbers in our mouths and throats to those we depend up on to help us to digest our food to the complex design of our immune systems, and so on. 

The problem is, this “natural” mode of being also, until relatively recently, entailed extremely high levels of entirely natural death to disease (an estimated 30 to 50 percent child mortality rate in the European Middle Ages, for example).  It is a hard truth that, as Darwin or Malthus or one of those 19th century naturalist boys first observed, it is the cruel way of nature that every species generates far more offspring than can ever survive into adulthood. That includes or used to include humans.

For the last century we lucky residents of advanced-industrial countries have lived comparatively free from fear of contagious bacteria, without really having to limit our activities in the microbe-infested world.  However, our antibiotics are and will continue to lose their effectiveness, both through inevitable natural selection and because of our stupid squandering of these treasures by, for example, feeding them to our livestock. 

It is possible that we will continue forever to discover new antibiotics and keep one step ahead of the evolution of harmful microbes, but it seems pretty likely we won’t.  (In any case it’s not looking too promising so far, with the emergence of drug-resistant TB, staph, salmonella, etc.) 

Even in a re-contagized world, mortality rates would not be likely to equal those of the Middle Ages because of our far greater understanding of how germs work.  On the other hand, in the past couple of generations we’ve gotten used to a pretty low level of risk, and we won’t tolerate much of it.  That is why there has been so much media hype over things like pandemic flu (which previous generations didn’t bother to retain in their collective memory despite millions of deaths in 1919) and West Nile virus.  A lot of people will go to great lengths to protect themselves the first time we again encounter a truly widespread bacteria that is a) deadly, b) casually transmissible, and c) not treatable by antibiotics. 

Then, as more and more bugs evolve back into real threats, fearful people –- legitimately fearful people –- will find themselves living with masks, cleaning routines, isolation habits, and general sterile living.  Aided by ever greater technological sophistication, we might increasingly drift apart from the kind of free and open lives humans have always lived –- gamboling in the forests, walking in the fields, playing in the dirt, exploring the cities.  Other people, feeling that separation intensely, will probably decide to take their chances and live freely among the bugs. 

So that may turn out to be the true bifurcation -– a split between the bubbled and the unbubbled.  If the split were persistent enough, the two groups would even evolve differently over time, with the higher mortality of the unbubbled leading to greater innate resistance while the bubbled would become more and more fragile and dependent upon their technological bubble.  They might also evolve different social characteristics –- the bubbled living with much greater social stability due to low mortality but dependent on the unbubbled, perhaps, and the unbubbled living with greater freedom but also the instability of high mortality.

Anyway, that’s the sci-fi vision I had recently.  In reality, I think everyone will probably end up with some combination of high-tech protections, and just sucking up the greater risk.  (It is also possible, of course, that some new medical technique, aside from antibiotics, allows for permanent conquest of the bacterial threat).

Fading sensations

I read a fascinating article (pdf, 863k) in the August 2007 Scientific American that has implications that seem broader and broader the more I reflect on them.  According to the two neurophysiologists who authored the piece, when it comes to our eyes, constant input fades away – as they put it, "an unchanging stimulus leads to neural adaptation in which visual neurons adjust their output such that they gradually stop responding." In other words, because of the wet chemistry of our retinal light sensing cells, unchanging stimulation ceases to produce a reaction. Since unchanging objects do not generally pose a threat, the article explains, "animal nervous systems have evolved to detect changes in the environment." Frogs, it turns out, are an "extreme case" of this because things not moving are actually invisible to them (the dinosaurs in the original Jurassic Park were supposed to be the same way; I was always curious about the basis for that.)

The reason our eyes are constantly in motion, jerking around with tiny little hops (called saccades and microsaccades) even when we think we're staring at a fixed point, is that human eyes create their own motion so that our visual field isn't constantly fading.

To prove to yourself that this neural fading (called the Troxler Effect) is real, check out this optical illusion (there's also an interactive version, and another illusion based on the same principle and just a whole bunch of cool optical illusions in general).

In the lab they can completely halt these microscopic eye motions, and they have found that your entire field of vision then fades away. In fact, if it were not for this effect, you would constantly see blood vessels in your eyes (which move with your eyes & therefore are faded).

(I wonder if this is in some way analogous to what takes place with video compression.  As I understand it, most compression algorithms work by recording only those portions of each frame that are different from the preceding. So those parts of the image that are unchanging are effectively ignored – just like with our vision. I wonder if our cells evolved this way not just because of the adaptive advantages of identifying motion as the authors mention, but also because there are processing efficiencies involved for the computation performed by the brain (note that according to the authors, the fading effect takes place at the level of the neuron, not at the processing level of the brain, where other "fadeouts" – for example, someone nagging you – must occur.)

But for me the most exciting point of the article, an aside which made it leap out as something of broader interest and relevance than just an ocular biological quirk, is that:

Neural adaptation takes place in all the senses, including touch.  For instance, you may feel your shoes when you first put them on in the morning, but the feeling goes away after a while.  You probably do not want to be aware of your shoes 16 hours a day, after all.  If you wiggle your toes, however, you can feel your shoes again. Similarly, fixational eye movements constantly "wiggle" the images on the retina so that your vision never goes away.

That just makes sense in a ton of ways.  It explains why smells fade, why you can't tell what your living room smells like, why you taste a glass of wine most vividly with the first sip, and by the last, it's pretty much just wine (or is it just me?).  It explains why you can enjoy food more if you alternate bites of two dishes, or eat food (even a sandwich) that is made up of mixes of different foods so that all the bites are constantly changing mixes of ingredients.  And many other things. It was just a major "aha" for me.

Also, as a barefooter I cannot resist pointing out the personal aptness of the example the authors chose to use above: the loss of sensation that comes from wearing shoes.  When we go shoeless every step brings fresh sensations.  Combined with the fact that, as a doctor friend tells me, our feet have more nerve endings than any other part of our body except for our hands and our sex organs, this helps explain why barefooting opens up an entire new world of sensation that is otherwise deadened and closed off to us. (Update: see this post on world of barefoot sensation)

This neural adaptation also represents a danger for athletes, however.  Every runner knows that when you are feeling pain, it will usually fade if you just keep running.  Often, "running through" pain, as it's called, is an excellent thing, keeping various harmless aches and pains that we all experience from immobilizing us.  But in some cases, it can be a dangerous clouding of urgent bodily signals that we are doing mounting damage to our bodies, as with tendonitis or a bone fracture.

Perhaps not just bodily pain but also psychic pain also fades with time – the pain of grief, of regret, of guilt, of embarrassment or humiliation.  Maybe if such pain doesn't fade away it is because there there are psychological "microsaccades" that keep the pain fresh.

Also, pleasure.  Even the finest delicacy, if eaten too frequently, begins to fade in the pleasure it gives.  How does the rich person, who can eat at the finest restaurants every night, ever derive the pleasure from the experience that a poorer person, who can only do so rarely, will?  How does one "wiggle" one's happiness?  Perhaps we can think of pleasurable activities that involve wiggling of one kind or another, but this line of thinking confirms what I've always believed about happiness, which is that it is immensely relative.  It's always seemed to me that people are happy when things are getting better for them, and unhappy when things are getting worse, and when things stay the same, people's satisfaction level floats back to an even keel or personal default psychological state.  (Complicating this is the issue of expectations, which is what defines improvement or decline for people.) 

This implies that the happiest person is he or she who starts off life in very dire circumstances and whose life steadily improves over its course.  The unhappiest person would be the person whose life follows the reverse course.  People whose circumstances remain the same – whether they are born in a shack or in a mansion, would be predicted to experience roughly equal levels of happiness.

Just as with neural adaptation, it is movement that produces sensation, whether good or bad.

Of course, that's assuming a certain baseline level of physical comfort, I imagine.  While the person who sleeps on a rough floor will probably get used to it (sensory adaptation again) and be none the less happy for it, hunger and disease are not likely to be subject to the effect.

I previously posted on the ancient Greek thinker Democritus, who said:

you should consider the lives of those in distress, reflecting on their intense sufferings, in order that your own possessions and condition may seem great and enviable, and you may, by ceasing to desire more, cease to suffer in your soul. . . . If you keep to this way of thinking, you will live more serenely, and will expel those not-negligible curses in life — envy, jealousy and spite.

In light of the Scientific American article, Democritus's advice to reflect upon the worse circumstances of others now sounds to me like a form of psychological saccade or "wiggling" that will improve your own happiness by making your soft plush bed and other luxuries and attainments seem fresh once again.  The same effect could be achieved by reflecting on how much better your life is than it once was.  And envy and jealousy – as well as regret – mean imagining your life as better than it is, which is psychologically the same as experiencing a downward movement in your circumstances, which results in unhappiness. 

Mosquitoes & chemicals - update

So I had an extensive conversation the other day with the head of Arlington's Environmental Health Bureau, Richard Cole,  about the spraying of pesticides near my house in reaction to the threat of West Nile Virus.  So far in the years we've lived in Arlington I've had a very favorable opinion of all the interactions I've had with Arlington county government, and Mr. Cole was no exception.  He was open and professional, and responded patiently if not always with crystal clarity to the pointed questions I posed to him on this matter.

That said, the conversation in the end didn't do much to dispel my doubts about the rationality of these mosquito sprayings.  Here are some of the things I learned:

• He did not dispute my characterization of the level of risk presented by West Nile (as significantly less dangerous than the flu).  He did make the point that there is a vaccine for flu, but not for West Nile.  I'll have to go back and look at the CDC numbers I used; if they are the death rates that exist today even with the vaccine then his point would not hold.
• He said the mission of his bureau was "to protect public health" overall, but specifically through a few means including restaurant regulation, pest and rodent control, and preventing the spread of disease. To me that suggests that what we have is an bureaucracy that is focused on its particular mission (stopping disease) and that there may not be a proper balancing of competing risks taking place during the decisionmaking process. 
• It also confirmed my suspicions that media hype and political reaction rather than sober calculation is driving this.  Cole told me (I took notes and am a very fast typist): "If all of a sudden the news hit that we have a number of people in Arlington that were sick, I'd feel like I wasn't doing my job right, so that kinds of drives our decision process."  There has been one human case in Arlington (he's doing fine).  It is understandable that the person held responsible for protecting the public from a threat will do everything he can to avert that threat, especially when it's a major sexy media interest, but it is up to his political superiors to keep that threat in perspective and balance it against others.  But of course they don't want to answer to the media any more than he does.  And pesticides – its risks are diffuse and hard to pin down.  For a politician, the choice is easy.
• Cole admitted that the sprayings would have to be repeated indefinitely since they would in no way eradicate the mosquito, but just kill those directly hit.  "It's a temporary fix; it's not in the long term going to prevent more mosquitoes from breeding," he told me.  For a long-term fix, you would have to have a program like helicopter spraying of the entire county, and Arlington has chosen not to do that, he said.  Seems to me even if you did do that, the mosquitoes would still flood back.  This is like trying to clear floodwater with dynamite:  wherever you set off a stick, the water will be flung back and you'll see dry ground – but it won't last long.  We are faced with a choice between indefinite repeated applications of local pesticides, and the dangers that brings (the creation of resistant mosquitoes, for one thing), and just accepting the existence and small danger of West Nile as a fact of life.
• The substance that was sprayed was something called Permethrin.  Some online fact sheets, which as far as I can tell are not from industry front groups, say that Permethrin breaks down in the environment relatively quickly and does not pose a threat to groundwater, and is metabolized efficiently by mammals and does not persist significantly in body tissues.
• On the other hand, Permethrin is also a "broad-spectrum" chemical that kills indiscriminately, being toxic not just to mosquitoes but also to bees, mice, fish and many other species.  It is a neurotoxin and is classified by the EPA as a Category C ("possible human") carcinogen – basically what I take away is that really they have no idea how harmful it really may be. 
• On why the school next to my house kept its children inside on the day of the spraying, and what that implied for my children, I did not really get a clear answer.
• He assured me that "all EPA guidelines" were followed in the use and application of this pesticide. I wish I found that comforting.
  

This may be insanity, but it's an insanity much broader than Arlington County.  Nearby counties and many others across the nation are also doing this, Cole said, and I see online that Permethrin is used very broadly in agriculture (on cotton, corn and wheat) and in household bug sprays.

But I don't like having this dumped near my house.  In fact reading this stuff tonight I realize my son recently got a mysterious rash on his legs we at first thought was poison ivy, but which his doctor could not figure out the origin of.  It persisted for almost a week.  Reading about this pesticide, which can cause "redness, swelling, and possibly blistering" of the skin, I bet he got a dose.  Wonderful. 

I know/know of a lot of children with cancer.  I don't know of anybody who's died of West Nile.

Mr. Cole and the Arlington County Board and whoever else, I hope you really know what you're doing and that you're not letting the fear of sensationalist career-damaging headlines, or simply unexamined conventional wisdom and standard practice, distort your judgment.

Stumped and stuck

I wrote the other day about progress in physics – about the assumptions we all make about it and whether it will bring useful innovations. 

There is another possibility I didn’t mention: that, after all the breakthroughs that Einstein and Niels Bohr et al brought us early in the 20th century, and all the fleshing out of that paradigm shift that has taken place since, we get stuck and see no significant additional breakthroughs for centuries no matter how hard we try.  Maybe instead of an ever-acclerating pace of innovation, we have actually punched through some barriers, and are still mopping up from that accomplishment – but are now up against new barriers and things will slow down.

What if what Thomas Kuhn called “normal science” never generates a new revolution, because we simply never are able to gather enough pieces of the puzzle to pull it off?  (That might be, for example, because each new piece requires another $20 billion supercollider.)

Because we've lived at a time of constant scientific/engineering/technical innovation and discovery – in fact, it has been accelerating since the 14th century – we assume that will always be true.  But what if it doesn't?  Is that even imaginable? 

Innovation always moves with fits and starts in any one area; check out this jetliner – you wouldn't look twice if it flew by today, but it's a de Havilland Comet, the first successful jet airliner, which entered service in 1949.  If I had a 1949 computer, there'd be no danger you'd mistake it for something current (to begin with, it would be the size of a small house).  But other technologies such as automobiles and refrigerators are still being made today with only refinements to the same basic design as 1949, and earlier.  The path to land locomotion was long and steep, but not much has happened on that front since the internal combustion engine came along.

In fact it’s not even clear that technological change is accelerating, as measured by its impact on our lives. Jeff Madrick has written critically of the assumption that the computer revolution is bringing greater changes than ever seen before:

What about the steam engine, which reduced transoceanic and transcontinental travel from a few weeks to a week or less in the nineteenth century? Or the telegraph, to cite just one other of many such inventions? In the 1840s, it took ten days to send a one-page message from New York to Chicago. In the 1850s, after the telegraph was invented, it took a few minutes.

Think too about the effect things like electricity and the car had on people’s lives.

On the other hand, I do think the social effects of the information revolution will be long and deep, at least as long as Moore’s Law holds. 

But when it comes to the most basic science, like physics, it could be that we just get stumped and stuck, and that eventually all the engineering and technology implications and permutations of the basic science engine are worked out.  It could be that basic science is the sun that powers everything else and its death leads to a long cold death for the other areas too.

Okay, I don’t really believe any of this.  But maybe I’m just a man of my time who can't shake his deep-seated assumptions.  What if?

Diminishing Returns on Mastery of the Universe?

I've always enjoyed the history of science, and I'm fascinated in particular with the dilemma of quantum mechanics, which is that the only theories that seem to actually work in explaining the behavior of particles at the subatomic level are also bafflingly messy, counterintuitive, ad hoc-feeling and, as many physicists feel, "not beautiful."  Einstein for his part famously rejected them (and spent most of his life as a bit of a scientific outcast as a result).

Many people feel that the situation we are now in is akin to Ptolemaic astronomy, in which the motion of the planets, which were understood to revolve in perfect circles around the earth, were explained through the construction of an ever-more complicated, ad hoc system of cycles and cycles within cycles (epicycles).  Beauty and simplicity were restored to this messy system through Kepler's laws of planetary motion and Newtonian physics.

Some physicists, feeling that there must be some similar underlying unity behind the ad hoc theories of quantum physics, are searching for a new Kuhnian revolution, a Grand Unified Theory (that will for example encompass gravity, which has kind of been left out of quantum physics). The whole thing is really fascinating and dramatic.  Will some startling new insight emerge that once again restores some order to physics and makes it accessible to human intuition?  Will string theory, upon which many are pinning their hopes, do the trick?  Or will physics just continue to get weirder?

I've been thinking lately that it's funny how there's an assumption that if a new breakthrough is reached, it will have huge consequences.  The quantum revolution, after all, produced nuclear energy and weapons, and the transistor, which revolutionized modern life and still is doing so. 

But it could be that, as we get better and better at manipulating our universe (however much social-historical arbitrariness there is in the direction of scientific exploration, that's basically what appears to be happening), successive revolutions have less and less impact.  So the next revolution will refine our ability to manipulate the world.  And the next one refine it even further, and so on, in ways that are progressively less directly related to our everyday life.  So, the social utility of sucessive revolutions in physics declines as the subject of study becomes smaller and smaller and actually begins to lose applicability to practical life. Even as it gets more and more expensive to figure out the next smallest level of reality, with multi-billion-dollar supercolliders and other 'big science,' it becomes less important for reducing suffering and increasing the comfort of mankind.

Of course, a new explanatory theme for physics such as string theory could also burst open entirely new doors like interstellar space travel, or bring things as unimaginable to us as the transistor was to Ulysses S. Grant. This suggestion of mine could easily appear laughable in a century in light of events to come, like the famous (but apocryphal) nineteenth century patent office guy who supposedly resigned because he thought that everything that could be invented already had been.  But the possibility that new scientific discoveries could actually get less and less important, is an idea that shocks the contemporary sensibility.  So I like it.

Apocalypse: eco-collapse

Even with all the attention finally being paid to global warming, I believe most people are seriously underestimating the possibility of sudden, drastic, truly frightening changes in our climate.

I've done a lot of reading about the subject that was once popularly known as "chaos theory" and more recently and broadly has come to be known loosely as complexity theory. Among the subjects this encompasses are nonlinearity, self-organizing systems, emergent behavior, fractals, reflexivity, feedback effects, cellular automata, and evolutionary algorithms. (Here is a good introduction, but there are many others books on the subject.  Malcolm Gladwell’s book The Tipping Point seems to be a businessy popularization of some of these ideas focussed on social examples, though I haven’t read it. )

One of the things that you develop when you focus on this subject (I also spent a lot of time back when my life was simpler playing around with fractals) is what has been called a "nonlinear intuition."

To oversimplify greatly, a linear relationship is one that follows a predictable path. If your temperature rises 5 degrees, you get 3 more inches of rain; if it rises 10 degrees, you get 6, etc. A nonlinear relationship enters the picture when, say, there's a mountain range, and if the temperature is above 60, you always get 3 inches of rain no matter what, but if it falls below 60, the clouds can no longer make it over the mountain range and you get zero. So, a 1-degree change at a certain point has drastic effects. That's nonlinear.

I didn't choose that example at random, of course, I read somewhere a few years ago that a relationship like that actually holds true in the Himalayas or somewhere.

And the larger point of course is that weather systems are like that – they are very nonlinear.  Pumping x more tons of CO2 into the atmosphere will not necessarily have smooth, predictable effects.  Someone once put it like this:  if you take one rivet out of an airliner, nothing is going to happen. But if you keep removing them, at some point you will have a sudden catastrophic failure – the airplane will crash.  If you pump a little carbon dioxide into the air, nothing happens, but at a certain point, the ice caps tumble into the sea, or the jet stream flips direction, or – who knows?  Something crashes.

The result is that we're in a much, much more precarious situation than most people, with their linear intuitions, realize. Spontaneous global eco-collapse is a distinct, though probably remote, scientific possibility. Spontaneous much-bigger-than-anyone-expected eco-disruption is not only a possibility but perhaps frighteningly likely.  Global eco-collapse is one of my (slightly tongue-in-cheek) "Seven Paths to Apocalypse" – but this is no joke.

I was hoping Gore would try to capture some of this in his movie, and he did allude to it a little if I recall, but even among that slice of the population that watched it, most, lacking a quirky interest in complexity theory, are not likely to catch the full flavor of the danger we may be facing.

News reports have been suggesting for the past several months that in the arctic we might be seeing just the kind of feedback effects that can lead to catastrophic changes.  The melting of arctic ice is

a)    reducing the amount of solar heat that is reflected back into space
b)    accelerating the release of C02 that had long been trapped in the soil beneath the ice

Both of these effects of melting have the effect of increasing the pace of melting. That is just the kind of self-referential loop that leads to unstable nonlinearity and sudden discontinuities – aka big trouble.  Ironically, what is often called a "snowball effect."  I bet we're seeing it in the arctic because that's where we're looking most intensely – but it could happen in all kinds of ways in all kinds of places.

Just to get away from the ice caps, for example, did you know that the world’s coral reefs are crucial regulators of oceanic carbon dioxide and calcium, and are home to a quarter of all marine life?  Did you know that a quarter of the world’s reefs have been destroyed, for example in the 1997-98 El Nino event, which killed 70% of all corals in the Indian Ocean from Africa to India?

Most of the media attention paid to global warming has been focused on a couple effects of the warming: the rise in sea levels, and the effects on species, such as polar bears.  There has also been some discussion of an increase in hurricanes (since hurricanes are apparently nature’s way of transferring heat from the tropics toward the poles).

These are all essentially linear-minded (if totally valid) concerns.  Warming goes up, sea levels go up, polar bears die, hurricanes increase.  Warming goes up more, sea levels go higher, more polar bears die, more hurricanes hit.

What we should be most focused upon is the very real danger of sudden, unpredictable, radical changes in climactic conditions in some or many parts of the world. 

West Nile Virus - hype or real risk?

Arlington County Virginia, where I live, announced today that they were going to be spraying pesticides in my neighborhood because local mosquitoes have been testing positive for West Nile Virus, and a human case has emerged. (They're also keeping all the children at my kids' elementary school indoors during some of the most beautiful weather we've had in months.)

I wonder about this. I’m curious about the cost-benefit calculations, and suspicious that, as is so often the case these days, the calculus is all whacked because of media-driven hysteria over a novel phenomenon with an exotic name that has led to a perception of risk out of all proportion to reality.

The security expert Bruce Schneier likes to say (to paraphrase) ‘if you read about it in the newspaper, you shouldn’t be afraid of it.’  The fact that it’s in the media is a sure sign, he says, that the danger in question is unusual or freakish –- while its the things like slipping in bathtubs or falling down stairs that really get you.  Or the flu.

Is West Nile Virus really dangerous enough to warrant the dumping of god knows how much pesticide into our community (grass, plants, soil, water tables, insects, animals’ bodies, insects again, rivers, etc)?  (The authorities claim the pesticide is “safe” – another question is how much faith to put in that claim, but that’s a separate matter, even if for me it’s not a whole lot.  It ain’t safe for mosquitoes anyway, I guess).

I turned to the CDC to see what I could find out. There I read that “approximately 80% of people who are infected with West Nile do not show any symptoms at all.”  I read that about 1 in 150 of people who become infected will develop “severe illness,” and that of that 0.66% who get severe illness, “case-fatality rates range from 3% to 15%.”  If my calculations are right that means between 1 in 1,000 and 1 in 5,000 of people who are infected will die.

How does that compare to the flu?  The CDC says:

Each flu season is unique, but it is estimated that, on average, approximately 5% to 20% of U.S. residents get the flu, and more than 200,000 persons are hospitalized for flu-related complications each year. About 36,000 Americans die on average per year from the complications of flu.

5% of the US population of 300 million is 15 million; If 36,000 of them die, then that would be ~1/4 of 1%, or 0.23%, or 1 in 417 people.

20% of the US population would be 60 million; if 36,000 of that number die, that would be ~1/20 of 1%, or 0.06%, or about 1 in about 1667 people. 

So according to the CDC’s figures, the death rates for each range from

• West Nile: 1 in 1000 to 1 in 5000
• The Flu:  1 in 417 to 1 in 1667

Maybe I’ve made a mistake in here somewhere or am missing some other key factor, but it looks to me like West Nile Virus is considerably less dangerous than the flu.

One thing that would be interesting to know in the case of both types of virus is how many of these fatalities are cases where a sick person who is on their last legs anyway gets dealt their final death blow by the virus.  I suppose if the flu was mostly knocking out the vulnerable, while West Nile was striking down the healthy, that would make West Nile more dangerous if viewed in terms of “expected years of life cut short,” which would strike me as a legitimate way of evaluating a risk.  But, the CDC does say that West Nile fatality rates “are highest among the elderly.”

I wonder if our public health authorities have sat down and seriously thought this through (hopefully with some ecologists at the table) or if they are just responding to hysterical constituent calls.

I wonder if they would dump pesticides and shut my children up in school to prevent a slight risk that someone would get the flu.

Why "Proper Form" is Elusive

As a triathlete, I’m always reading about how important it is to use proper form in running, swimming and biking.  And of course similar advice is routinely handed out in every other sport as well.  But all this advice needs to be taken with a big ol’ grain of salt (see previous post on same theme).  Here’s why:

In mathematics there’s something called the “traveling salesman problem,” which is really very simple.  Imagine 4 cities spread out on a map, various distances away from each other.  The question is, what route should you take so that you visit each of those cities, yet travel the least distance possible?   

When there are only four cities, it’s easy to solve.  But once you start to expand the number of cities, it quickly gets very difficult – with only 25 cities, there are so many possible routes that a computer measuring one million per second would still take 9.8 billion years to search through them all. (I get this from Peter Coveney and Roger Highfield, Frontiers of Complexity [1995], a thrilling and mind-blowing book that I highly recommend to anyone interested in such things).

Mathmaticians call this kind of problem an NP Problem – one that is not solveable in “polynomial time.”  There are a number of real world and mathematical problems that manifest this quality of seeming relatively simple to solve, yet which quickly spiral into unmanageable dimensions as you add more factors.  (Among them is the problem of factoring very large numbers, which is what modern encryption is based on and why it is currently unbreakable through brute force mathematical attacks.  It’s easy to multiply a bunch of prime numbers together and get the product, but it turns out it’s next to impossible to reverse the process.)

Anyway, I think about this whenever someone starts lecturing about “proper form.”  Imagine that you are engineer trying to figure out the most efficient way to move human limbs through water for swimming, or across the ground for running, or through space for kicking, batting, throwing, or whacking golf balls.  You have to take into account the particularities of the specific human body you are looking at:

• The size (and possibly strength, flexibility and density) of each bone that is involved in that movement (for many movements, that would be every major bone in the body)
• The strength, flexibility and elasticity of each muscle involved. 
• You may also need to factor in differences in muscle composition, such as the proportion of fast twitch and slow twitch muscle fibers
• Perhaps other more diffuse differences in metabolism, which could also affect what is the optimum way for a particular person to perform an activity.

I bet that finding the optimum form for a particular person would be an NP problem – a problem with so many variables that no computer could find the best form for you in your lifetime – let alone a single solution that fits everbody (every body).

The way we each tackle this problem seems to be through an approach of evolutionary learning – we flail around more or less randomly (as babies), and eventually through trial and error and the feedback of getting what we want (grabbing a toy when we’re young, getting the ball through the hoop, say, when we’re older), we hone our movements into more and more efficient forms. One way we do this is by trying something, and then adjusting it in different directions to see if our results improve. 

But another thing that Coveney and Highfield talk about is that you can picture the set of all possible solutions to an NP Problem as a topographical landscape.  As you try moving in different directions – adjusting things – you see if you move up hill (toward better solutions) rather than downhill (toward worse ones).  Then, you keep making adjustments until you have gone as high as you can.  The problem is that you might reach the top of a local peak, while there is a much higher peak – a more efficient solution for you – that lies somewhere else in the “solution space.”  And to take advantage of that you'd have to radically restructure and rebuild your stroke from the ground up.  (One person who made the leap and did exactly that is Tiger Woods - an amazing thing.)

So all that is why talk about “proper form” should be taken skeptically.  For your own biomechanics (and biochemistry), there may be one or many completely different forms that will work better than what you are now doing.  That coach who’s yelling at you to change the way you’re doing things is basing that on (best case) nothing more than an approximation of what has been found to be more or less effective by a lot of other people, or (worst case) the current fashion for how things should be done, perhaps based on what has worked for a few elite (and not necessarily typical) athletes.

Of course, there are some basic parameters of physics in every activity.  Also, if you’re a total newbie at something, you’re probably best off listening to a coach to provide some structure to your early flailing.  If you’re reasonably accomplished, the coach will probably just be helping you to try different adjustments in what you’re already doing to see if you can eke out some improvements.

The difficult case would come if you are accomplished at something, self-taught, or a “natural,” and some coach tells you that you’re doing it “all wrong” and tries to get you to completely restructure your form.  Then you have to decide whether to stick with your own body’s evolved solution, or leave that mountaintop and try to find another, higher peak through the textbook solution.  You just can't be sure the peak really is higher.

If you look at successful runners or other athletes or others like pianists, you’ll see a tremendous variety of forms.  There would probably be even more if various trends and fashions didn’t regularly sweep through instruction, standardizing the way people are trained.