A black swan event is the idea that things that were never imagined do come to pass. The idea was recently popularized by Nassim Taleb 1. The concept dates to the seventeenth century when “Black” swans were thought of as impossible events (since all known swans were white). However, Dutch explorer Willem de Vlamingh went to western Australia in 1697 and discovered a black swan. Illustrating that the unimaginable can come to pass 2. Black swans are unknown unknowns.