Lorenz Attractor:
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"The term 'sensitive dependence on initial conditions' was coined to describe the phenomenon that small changes in a recursive system can drastically change the results of running that system. A term Lorenz coined to describe sensitive dependence on initial conditions is the 'butterfly effect.' This is another thought experiment which is hardly testable: imagine that there exist two earths, so that an incorporeal observer could compare events on one earth to another. Now imagine that both earths are identical except for one fact; in one, a butterfly flaps its wings somewhere in South America, and in the other, this butterfly remains still. One might think that such a small discrepancy between the two earths would be inconsequential; after all, nobody was there, nobody could even notice the butterfly's wings flapping, and air currents would be affected only minorly by such a miniscule event."
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SO FLAP YOUR WINGS OH BUTTERFLY - MAKE A DIFFERENCE - LRK -