Butterfly Effect
"In Chaos Theory, the butterfly effect is the sensitive dependence on initial conditions in which a small change in one state of a deterministic, nonlinear system can result in large differences in a larger state." In other words, a butterfly flapping its wings in Texas can cause a typhoon in the Japanese Sea later.
Think about it, in mid-20th Century America, an 18-year-old hippie, freshman s**t in a Honolulu college had sex with an older, alcoholic Kenyan politician on a student visa, who had a wife and child back in Africa.
And from this "roll in the hay" comes the collapse and dissolution of the United States of America in the 21st Century.
Interesting isn't it. It makes you a firm believer in the "butterfly effect".