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Yesterday I read Alan Greenspan’s recent article in Foreign Affairs magazine (hat tip Rhoda Schermer). It is entitled “Never Saw It Coming: Why the Financial Crisis Took Economists By Surprise,” and for those of you who want to save some time, it basically goes like this:

I’ll admit it, the macroeconomic models that we used before the crisis failed, because we assumed people financial firms behaved rationally. But now there are new models that assume predictable irrational behavior, and once we add those bells and whistles onto our existing models, we’ll be all good. Y’all can start trusting economists again.

Here’s the thing that drives me nuts about Greenspan. He is still talking about financial firms as if they are single people. He just didn’t really read Adam Smith’s Wealth of Nations, or at least didn’t understand it, because if he had, he’d have seen that Adam Smith argued against large firms in which the agendas of the individuals ran counter to the agenda of the company they worked for.

If you think about individuals inside the banks, in other words, then their individual incentives explain their behavior pretty damn well. But Greenspan ignores that and still insists on looking at the bank as a whole. Here’s a quote from the piece:

Financial firms accepted the risk that they would be unable to anticipate the onset of a crisis in time to retrench. However, they thought the risk was limited, believing that even if a crisis developed, the seemingly insatiable demand for exotic financial products would dissipate only slowly, allowing them to sell almost all their portfolios without loss. They were mistaken.

Let’s be clear. Financial firms were not “mistaken”, because legal contracts can’t think. As for the individuals working inside those firms, there was no such assumption about a slow exhale. Everyone was furiously getting their bonuses pumped up while the getting was good. People on the inside knew the market for exotic financial products would blow at some point, and that their personal risks were limited, so why not make systemic risk worse until then.

As a mathematical modeler myself, it bugs me to try to put a mathematical band-aid on an inherently failed model. We should instead build a totally new model, or even better remove the individual perverted incentives of the market using new rules (I’m using the word “rules” instead of “regulations” because people don’t hate rules as much as they hate regulations).

Wouldn’t it be nice if the agendas of the individuals inside a financial firm were more closely aligned with the financial firm? And if it was over a long period of time instead of just until the bonus day? Not impossible.

And, since I’m an occupier, I get to ask even more. Namely, wouldn’t it be even nicer if that agenda was also shared by the general public? Doable!

Mr. Greenspan, there are ways to address the mistake you economists made and continue to make, but they don’t involve fancier math models from behavioral economics. They involve really simple rule changes and, generally speaking, making finance much more boring and much less profitable.