Black Swan Theory --  Rare bird, assumed not to exist.  Hense, an
unexpected events of large magnitude and consequence and of a dominant role in history. 
Such events, considered extreme outliers, collectively play vastly larger roles than regular occurrences.
	Examples:  Internet, PC ; birth control pill ; WWI, 9/11
Only rationalized to be understood after the fact.
	Mathamatical forecastings, as I used to do, cannot acknowledge Black Swans  
I allowed manual over-ride to entertain new conditions about which we had no experience.
	Theory has interest in finance, stock market, government, ...