Frankly, Black Swan is an event of unprecedented gravity. It is an event of such magnitude that it completely changes the perspective of humanity. These events are classified by their extreme rarity and catastrophic impact on the world economy and cannot be predicted by any standard models. Black Swans are by definition completely unpredictable, at least that is what we are told and think today. However, some over the years have come to the conclusion that black swan events are in fact more than just predictable and have cycles that run for about 90 years. In other words, it is believed that people will make the same mistake every 90 years, and that history will repeat itself no matter what you do.