Public Policy Meets Complexity

Good intentions and the urge to get something done can lead to disastrous policy. This is true for everyone. But add the power of government to compel obedience and the need for politicians to harvest votes and champion causes, the "obvious solution" can as often as not make the problem worse. When "compassionate" government "needs to do something", watch out.

Back around 1870, bridge builders noticed an illness affecting those who worked inside caissons on the river bottoms while building the bridges' foundations.  The illness was called "caissons disease" and was similar to the illness noticed in some deep miners.  The natural solution was to get ill workers into normal air pressure as quickly as possible.  Common sense, right?

Not only wrong, but dead wrong.  The bends killed 14 workers on the Eads bridge over the Mississippi and 20 workers on the Brooklyn bridge.  It disabled several more, including John Roebling, the chief engineer on the Brooklyn bridge.  As we now know, the trick to relieving the bends is to get out of the high pressure environment slowly, not quickly.

But we're smarter now, right?  We know science.  We know that the Coriolis effect is the reason water drains down a tub counterclockwise in the northern hemisphere and opposite in the southern.  We know the Bernoulli effect on an airplane's wings is what makes it fly.  We know the gyroscopic effect is the reason a bicycle is so easy to ride.


Things aren't always simple.  In each case above, someone tried to give a simple explanation of what are really complex situations.  In fact, the coriolis, bernoulli and gyroscopic effects are real and do have some role in the above situations.  But the effects are negligible compared to other forces in these examples.

The forces on an airplane's wing, for example, are governed by the Navier-Stokes equations, a system of five partial differential equations that would make your head spin or earn you a PhD if you could find a solution method even slightly more efficient than those currently used.  A simplified approximation of bicycle dynamics requires 27 equations and 25 parameters.

Did we discover the answer to caisson's disease from first principles, by discovering the mechanism of the bends, nitrogen bubbles in the blood, etc.?  No.  It was discovered by observing different workers do different things and spotting the patterns.  One pattern was that those who left the caissons slowly tended not to get as ill as those who came out quickly.  But there was nothing obvious about it.  Any pattern was ambiguous at best, and only noticed over time.

A well-meaning man of action doesn't want to just stand around and observe, he wants to do something.  And the normal instinct would be to get those poor souls out of those deep caissons as quickly as possible.

Herbert Hoover was a well-meaning man of action.  He was going to get us out of the Depression just like he had helped flood victims before.  As President he saw that new gold discoveries and deposits from overseas threatened inflation.  So the relatively new Federal Reserve Board did what it could to fight inflation.  Hoover knew that any financial enterprise must balance its books, so he raised taxes to keep the government's books balanced.  He knew that struggling businesses didn't need foreign competition, so he signed Smoot-Hawley anti-trade legislation.  He knew struggling workers would be hurt by job losses or wage cuts, so he encouraged businesses to keep employees at current wages despite business losses.

In every case, what the Hoover administration did only made things worse.  Instead of inflation, we got worse deflation.  Raising taxes dried up private investment when it was needed.  Anti-trade was both anti-business and anti-consumer right here in the U.S. as well as internationally.  Businesses not adjusting to business realities deepened and prolonged the pain.

FDR was also a well-meaning man of action.  He unmade one or two of Hoover's mistakes, but made more of his own.  Hoover's results: 25% unemployment by 1933.  FDR's results: 20% by 1937.  While the U.S. economy was 30% greater than Britain's in 1930, they were about equal a decade later.  The New Deal worked no magic, other than mesmerizing the American public.

Get the man out of the caisson as quickly as possible.  Improve the economy by monetary manipulation, raising taxes, impeding trade, and imposing wage levels.  Reduce poverty by redistributing wealth.  To each according to his needs; from each according to his abilities.

All these things make sense at some level.  Unfortunately, they rarely make sense in real life.

Well-meaning people wanted to save lives by putting airbags in all cars.  Automobile manufacturers warned that airbags would kill children.  Since common sense tells us that businessmen lie and saving lives is good, we took action and mandated airbags in cars.  A few years and a few decapitated 2-year-olds later, we found that "
airbags kill more kids than they save."

Our well-meaning leaders therefore decided to lower the power in airbag inflation.  Unfortunately, that would save fewer adults.  In fact, airbags might not save lives overall at all.  

Our leaders then made kids sit in the back seat, to be safe from airbags.  An unintended consequence was that every so often a parent forgets he has that kid in the car and the child dies of heat or hypothermia.

Well intentioned people wanted to save lives in Africa.  We knew that Africans were not getting enough vaccinations, so we gave them vaccines.  Unfortunately, Africa did not have the medical infrastructure to handle the task.  The unintended consequence was spreading AIDS throughout that continent.  "Dirty needles accounted for almost half of all cases" of AIDS in Africa.

Well intentioned people wanted to save all species of birds and eliminate cancer.  They thought DDT killed birds and caused cancer.  So we outlawed DDT in the U.S. and penalized other countries who used it.  It turned out that DDT does not harm birds or cause cancer, but that it saves about a million lives a year in preventing malaria.   Now, several million lives later, the United Nations, the Sierra Club and Environmental Defense advocate the use of DDT to fight malaria.

Well-meaning people want to conserve the earth's resources.  So they drive hybrid cars to save energy, and would love government to force the rest of us to do the same.  It turns out that hybrid cars use more energy, when accounting for the car's complete life cycle rather than simply its fuel mileage.  "The industry average of all vehicles sold in the U.S. in 2005 was $2.28 per mile, the Hummer H3 was only $1.949 per mile.  That figure is lower than all currently offered hybrids and Honda Civic at $2.42 per mile."

Well intentioned people favor organic foods to save the environment.  It turns out organic farming is cruel to animals and harmful to the environment.

Well intentioned people think the U.S. should join the Kyoto treaty because we are the major contributor to carbon dioxide, a cause of global warming.  Despite what you think about global warming, North America consumes more carbon dioxide than it produces.  North America is already removing every bit the carbon dioxide it produces, plus some of the rest of the world's as well.

Maybe some facts are not as straightforward as painted above.  After all, things like DDT's effects on the environment are not simple -- maybe not as complex as the dynamics of a bicycle, but still not simple.

But that is the point.  Things are not simple.  Good intentions are not enough.  It takes understanding.  Good intentions are killing people.  Outlawing DDT allowed perhaps 25 million preventable deaths.  Mandating airbags caused children to die who otherwise wouldn't, in agonizing ways, and maybe has not saved lives at all.

If a bicycle is too complex to understand, why is everyone so sure he knows how to run the world?

I ask one thing of our policy makers and well intentioned voters.  Before you make something mandatory for all of us, would you please first ask yourself: how sure am I that this is really going to make things better?

Randall Hoven is an engineer living in Illinois.  He can be reached at
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