Opinion

# Emanuel Derman

## Counterintuitive, but true

May 9, 2012

I wrote a post a couple of weeks ago (Economists on the Skids) about the clear testability of counterintuitive ideas about mechanics and the much less clear testability of counterintuitive theses in economics.

Here is a counterintuitive truth I have discovered about the physical world.

Every Friday morning I get out of the subway at 34th and 7th, south-east side of the street, and proceed to walk to the middle of the south side of 34th street between 7th and 8th. To do so, I first have to cross the human river pouring out of the exit of Penn Station, shown below.

The thick white arrows denote the humans coming into Manhattan to earn their daily bread. They stream up the stairs and then through the anti-terrorist anti-vehicular barriers you can see in the photo, and then fight their fluid way onto the the 34th Street sidewalk.

The thin white line at the bottom of the picture has been my usual path. I approach from the subway exit at the left, hit the crowds and then move away from them to try to dodge the crowds as they spurt out of the barriers. It doesn’t work very well, because I am trying to cross, perpendicularly, all of these agents.

Last week I tried a new strategy: see the heavy red line at the top of the picture. I headed right into the dense thick of things behind the barriers. And Lo!, there they are moving slowly, held back by the barrier, and it’s easy to cross the flow. You easily emerge with them and go where you like.

Go into the thick of things and it’s easier to go where you want. Counterintuitive, but you can test it, and it’s true.

This reminds me of an argument I’ve had with people over taking different routes from one place to another by car. I always favor saving time. In some cases, this means sitting for a long time at a stop light; I have measured the time riding in someone’s car taking a roundabout route that involved no stop lights, but took 25 minutes from A to B instead of my timed 15 minutes the direct way. Distance matters.

Also, there is the controversial issue of traffic control measures. In all these cases, the objectively better solution is rejected (often quite emotionally) by those who either do not believe the math or apparently have values overriding their appreciation of a shorter commute time.

Posted by FranklinChen | Report as abusive

And interestingingly you “tested” one of those supposed difficult to form hypotheses from economics – namely that “regulation has unintended consequences”. I doubt the regulatory barriers were designed to speed Emanuel’s journey to work but that is the unintended consequence.

Posted by trader46 | Report as abusive

Do we accelerate into curves to maintain stability? Seem to remember that counterintuitive advice from driving instructor too many decades ago. Looked at Newton’s centripetal and centrifugal explanations in Principia, and waved at him as I to you. Do we need to comment for you to appreciate our appreciation at such wonderful thought waves for surfing? Can you count reads and time spent (or do you, to your chagrin?) to mitigate the difficulty in any thoughtful reply to what are (generally) poetically openended observations?
More output, right away, or face rebellion!

Posted by stevecharlson | Report as abusive

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