Dr. Martin Hash Podcast

The “Black Swan” theory of events correctly points out that just because a thing has never happened does not mean it cannot happen, even though people often make that assumption when doing predictions, and even if predictors had postulated that such events could happen, since they have not yet ever occurred, their probability cannot be measured, which means that any predictions made without considering them are misleading at best, and dishonest at worst. As insightful as this explanation seems, what really explains Black Swans is actually much more pedestrian. What's really going on is that there are an infinite number of possibilities with probabilities of occurring so small as to be negligible, impossible really, but not zero. Add enough of these non-zero possibilities together and there becomes a significant probability that one of them will happen.

Because Black Swan seems so elegant yet so inscrutable, it's often cynically invoked in combination with the possibly of catastrophic consequences as a justification for action on otherwise non-actionable possibilities; for example, an asteroid may hit earth and since that is a catastrophe of immense proportions, we must plan and prepare as if that event will occur. Climate Change hysteria is the ultimate purveyor of this kind of logic. Of course, as with any Complex System, the correct strategy is reactive rather than proactive, but fear-mongering for political reasons overrides conscientious science; just wait for the Black Swans to show up before getting your camera.