Problem is that these black swans happen only once in blue moon in a given area. For most other times if you look at trends, it's probabilistically correct to s

Problem is that these black swans happen only once in blue moon in a given area. For most other times if you look at trends, it's probabilistically correct to say that oil almost never goes down and real estate almost always goes up. I would estimate that there are less than 10 black swans occur during a life time of adult person that violates conventional "wisdom" in oil, stock and real estate. If you run your life believing that they would occur every year, you are likely to be at bigger loss. BTW, Nasim Taleeb don't suggest that you wait for one big black swan in one field like oil or real estate. His main argument is that you want maximize your exposure to all different kind of black swans in all different kind of places by putting lots of small bets on them. YC is a perfect example of implementation of Taleeb's theory. A bad implementation of Taleeb's theory would be to put a large bet that Apple stock would go down to $10.