"Before the discovery of Australia, it was believed in the Old World that all swans were white, a belief firmly established as it was confirmed by empirical evidence. The first sighting of a black swan must have been an interesting surprise for several ornithologists (and others who particularly care about the color of birds), but the significance of the story is not this. A single observation can invalidate a general statement that had been derived and confirmed by millennia during which we had seen only millions of white swans. All it takes is one (and, as I am told, somewhat ugly) black bird. In this (personal) essay, I take the risk and claim, against many of our thinking habits, that the world is dominated by the extreme, the unknown, and the highly improbable, while we spend our time focusing on the known and the repetitive. I also take the liberty to assert that, despite our progress and the evolution of knowledge or perhaps because of the progress and evolution of knowledge, the future will be increasingly less predictable, while both human nature and the social 'sciences' seem to conspire to hide this idea from us."

For Nassim Nicholas Taleb, the author of the bestseller "Fooled by Randomness," the Black Swan is the basis of all events in the world, from the emergence of religions to events in our personal lives. The Black Swan is an extremely improbable event with three main characteristics: it is unpredictable, it has massive consequences, and after its occurrence, we desire to make it appear less random and more predictable than it actually is.