Nassim Taleb’s latest interview with The Sunday Times is very well done and talks about the underemphasized issue of behavior in the absence of Black Swans. I had been thinking about the same topic over the last few days. Here are my thoughts:
The part of TBS that discusses being a fool in the right places is equally important as the part that discusses being conservative in Extremistan domains. In that respect, the chapter titled “Half and Half, or How to Get Even With the Black Swan” is my favorite and contains a succinct and personal kernel of the whole book. I think even the folks who understand the Extremistan ideas did not take away all that there is in the book on the other aspect: behavior in Mediocristan.
Let us consider a system of thought where “there is no logical reason to prefer one action over another.” In Extremistan domains, where the unknown plays a large role, it is beneficial to lean towards this system of thought. For example, if you are asked to invest in N securities, it is best to either invest in all of them, or none (if that’s a choice), instead of tunneling and showing a preference for a few over others. In this domain it is useful to value all choices equally beforehand, so we should not prefer one action over another.
However, it is possible to take this too far and apply this system of thought to Mediocristan domains. This will clearly lead to inaction. In a transaction involving exchange of goods, money, or time, a person who treats all choices as equal gains nothing from entering the transaction. He will exchange Object X for Object Y, but if he values X and Y equally, he gains nothing from the transaction. En fait, he will incur a transaction fee and come out at a loss. This would imply he is better off doing nothing at all, if he truly values everything equally (including his time). For example, if he knows that an MBA is valued fairly (it probably is, given the competition) and he values money and the MBA education equally, he has no reasons to apply at all.
So Taleb rails against the application of Mediocristan tools in Extremistan domains, but he is careful to point out that Extremistan thinking should not be brought into Mediocristan domains and he stresses the opposite. Many miss this point, and he emphasizes:
Few understand the beauty in the story of Apelles; in fact, most people exercise their error avoidance by repressing the Apelles in them.
If one decides to be hyperconservative in Extremistan domains, it becomes necessary to become hyperaggressive in Mediocristan domains. Otherwise, a part of us, the part designed to take risks, will be amputated.
So it becomes important to cultivate tastes, likes, and dislikes in harmless things. There are perils to being too open minded and valuing everything equally. The process of living in Mediocristan is trading-off what one doesn’t mind losing in order to acquire what one desires. For someone who has no particular likes or dislikes, this becomes very difficult and can lead to inaction. The stronger the likes and dislikes, the easier it will be to make decisions and trade-offs. These trade-offs are acceptable because the worst-case-scenario is clipped, these decision cannot hurt us more than a certain amount. A little diversification will wash the negative consequences out.
Creating an emotional differential between harmless choices in Mediocristan is what drives us - it generates action. This can be cultivated. It is difficult to put this in terms of “Gaussian risks,” so something may be lost in translation when the difference between Mediocristan and Extremistan is introduced.
Both takeaways from the book are important. Applying the one without the other leaves you lacking something important.


