Journal on Policy and Complex Systems
such unpredictable systemic behavior in the simple repetition of a handful of calculations .
Lorenz ' s 1972 talk on the topic was titled " Predictability : Does the flap of a butterfly ' s wings in Brazil set off a tornado in Texas ?" His answer was an emphatic " impossible to say " ( Lorenz , 1995 ):
If a single flap of a butterfly ' s wings can be instrumental in generating a tornado , so also can all the previous and subsequent flaps of its wings , as can the flaps of the wings of millions of other butterflies , not to mention the activities of innumerable more powerful creatures , including our own species . ... If the flap of a butterfly ' s wings can be instrumental in generating a tornado , it can equally well be instrumental in preventing a tornado . ( p . 181 )
It was Laplace ( 1814 ) who put forth the idea that if a magical demon could know everything there is to know about every atom in the universe , that demon could predict the future with perfect accuracy . Lorenz did not disprove Laplace ’ s idea ( an omniscient demon would not round numbers ), but he did show us that the demon would have to be far more omniscient than anyone had expected to have predictive power even in a simple , small simulation .
Gleick ( 1987 ) described the butterfly effect perfectly :
[ S ] uppose the earth could be covered with sensors spaced one foot apart , rising at one-foot intervals all the way to the top of the atmosphere . Suppose every sensor gives perfectly accurate readings of temperature , pressure , humidity , and any other quantity a meteorologist could want . ... The computer will still be unable to predict whether Princeton , New Jersey , will have sun or rain on a day one month away . At noon the spaces between the sensors will hide fluctuations that the computer will not know about , tiny deviations from the average . By 12:01 , those fluctuations will already have created small errors one foot away . Soon the errors will have multiplied to the ten-foot scale , and so on up to the size of the globe . ( p . 21 )
Now let me quote some lines from a few business books on complexity . From Goldstein ( 1994 ):
The butterfly effect refers to how air currents from a butterfly flapping its wings in Asia are amplified to influence the weather in North America ! ( p . 29 )
Merry ( 1995 ) explains it thus :
The inescapable conclusion is reached that man is living in a world in which under certain conditions , tiny causes can have enormous effects . This is called the butterfly effect . ... The flapping of the wings of a butterfly in Hong Kong can affect the course of a tornado in Texas . ( p . 30 )
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