We should maintain that if an interpretation of any word in any religion leads to disharmony and does not positively further the welfare of the many, then such an interpretation is to be regarded as wrong; that is, against the will of God, or as the working of Satan or Mara.
Buddhadasa Bikkhu, a Thai Buddhist Monk
Saturday, May 19, 2012
Black Swan Events Revisited
The point is that Black Swan Events are complex, and we have to be careful about how we use the term to understand the past. Taleb claims, for example, that they are unpredictable and unlooked for. The fact that we can't control them is part of their power over us. If that is the case, was 9/11 a Black Swan Event? According to the Wikipedia article, Rick Rescorla, "As the World Trade Center security chief for the financial services firm Morgan Stanley and Dean Witter, Rescorla anticipated both attacks on the towers and implemented evacuation procedures that are credited with saving many lives. He died in the attacks of September 11, 2001, while leading the evacuation efforts." Rescorla, obviously, did not predict the particular event of September 11, 2001, but he did anticipate the possibility of that event. He took steps to anticipate that possibility and thus actually exercised a (small) measure of control over it that saved some lives. So, was 9/11 truly a Black Swan Event? Or, again, was the assassination of President Kennedy such an event? The government had developed a whole set of personnel and procedures to deal with just such an eventuality, and while it is true that all of that preparation failed to prevent the assassination it was anticipated. It was known to be a possibility. Was it a Black Swan Event?
In determining what constitutes a Black Swan Event, more weight needs to be given to the idea that such events are unexpected rather than unpredicted. Many Black Swan Events were predicted by someone, but those who had the power to respond to those predictions and prepared for their potential consequences either ignored the predictions or did not even know about them—or, took a few ineffective precautions. We can know something about the future, but our knowledge is partial, uncertain, and easy to discount. As we know from political punditry, it is also often just downright wrong. And sometimes even when we anticipate them and take massive steps to counter-act them—such as is the case with presidential assassinations—we still fail to stop them. On the other hand, sometimes we do prevent them, such as the foiled attempt to assassinate President Reagan.
In an excerpt from his book, The Black Swan: The Impact of the Highly Improbable (here), Taleb writes a Black Swan Event is, "an outlier, as it lies outside the realm of regular expectations, because nothing in the past can convincingly point to its possibility." By this definition, Kennedy's assassination was not a Black Swan Event, however much impact it had on our world in 1963 and subsequently. We know that a presidential assassination is always a possibility. But Kennedy's death was a Black Swan Event. We didn't expect it. It had tremendous impact. And since 1963, we've expended tremendous effort to trying to understand the event. There was a presidential commission devoted to exactly that task. That is, we can correctly argue either way on this one. It both was and was not a Black Swan Event.
In sum, the actual nature of actual events in the real world are complex (even in our personal lives) and the concept of Black Swan Events does not do justice to that complexity. It may be a useful term in some ways, but it needs to be treated and used circumspectly. By the way, the term "black swan" goes back to ancient Roman times when everyone knew that all swans are white. "Black swan" described something that was impossible. Then, Europeans discovered Australia and learned that swans can be black, so the term eventually came to mean something unexpected. The discovering of black swans was thus a smallish but significant black swan event.