Beware those Black Swans

The bestselling economist Nassim Nicholas Taleb argues that we can’t make the world financial system immune to shocks –– but we can make sure it’s much more robust by building randomness into our planning.

Nassim Nicholas Talib in The New Statesman:

20100630_2010+26swan_w Let me summarise my ideas of how Mother Nature deals with the Black Swan. First, she likes redundancies. Look at the human body. We have two eyes, two lungs, two kidneys, even two brains (with the possible exception of company executives) – and each has more capacity than is needed ordinarily. So redundan­cy equals insurance, and the apparent inefficiencies are associated with the costs of maintain­ing these spare parts and the energy needed to keep them around in spite of their idleness.

The exact opposite of redundancy is naive optimisation. The reason I tell people to avoid attending an (orthodox) economics class and argue that economics will fail us is the following: economics is largely based on notions of naive optimisation, mathematised (poorly) by Paul Samuelson – and these mathematics have contributed massively to the construction of an error-prone society. An economist would find it inefficient to carry two lungs and two kidneys – consider the costs involved in transporting these heavy items across the savannah. Such optimisation would, eventually, kill you, after the first accident, the first “outlier”. Also, consider that if we gave Mother Nature to economists, it would dispense with individual kidneys – since we do not need them all the time, it would be more “efficient” if we sold ours and used a central kidney on a time-share basis. You could also lend your eyes at night, since you do not need them to dream.

Almost every major idea in conventional economics fails under the modification of some assumption, or what is called “perturbation”, where you change one parameter or take a parameter henceforth assumed to be fixed and stable by the theory, and make it random.

More here. [Thanks to Ali Altaf.]