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.