This document discusses how small individual decisions can have major consequences. It provides examples of how prohibiting drinking in the 1920s severely impacted social security in the US and how one woman's decision to sue for legalized abortion led to legalized abortion nationwide. The document questions what may have happened if bulletproof doors on airplanes were installed before 9/11. In summary, small personal decisions can result in large societal impacts, and minor changes may significantly alter outcomes.