Imagine you are a turkey who is being constantly fed by the butcher 364 days a year. You are happy, you know the butcher loves you, your economics and accounts departments are happy, they start to think this is the way of the world for you. Now comes the 365th day. You die. Just when your expectations levels reach their most optimistic, your destiny reaches its lowest point. But right before day 365 on day 364, you were 100% certain that you had a lifetime of bountiful happiness ahead of you. Day 365 was exactly contrary to the expectations of your finance department. Day 365 was the Black Swan which you did not anticipate. And yet it was that single Black Swan day that proved fateful for you, and not the earlier 364 days of well-fed bliss. According to Taleb, this is what most of us and especially the derivatives wizards on Wall Street are- happy, deluded turkeys.