New York City Subway: A Parable

A number of years ago, I was in the subway station under Times Square in New York City. I must have looked lost, because this fellow came up to me and asked me where I was going.

I said, "A bookstore, The Strand. I like to see what they have in their economics section. I am trying to decide if I should take the cross-town shuttle and go south from Grand Central."

He said, "I am an economist myself. You can have this subway map." And he handed me a map of the tube in London.

"This map is inaccurate."

"Of course. A map on a one-to-one scale would not be useful."

"I don't mean that. Here in New York, there is no circle line."

"It's called 'abstraction'. We don't care about curves between stations that do not matter."

"But this is just wrong for here."

"All models are wrong. Some are useful."

I finally saw I should just thank him, take the map, and back away. As I did, I heard him mutter to himself, "That guy does not understand scientific methodology."

I trust mainstream economists to help gather data for, for example, Simon Kuznets' National Income and Product Accounts and, for some, to provide guidance among data sources.