The Black Swan: Second Edition

by Taleb, Nassim Nicholas

• ISBN13: 9780812973815
• ISBN10: 081297381X
• Edition: 2nd
• Format: Paperback
• Copyright: 2010-05-11
• Publisher: Random House Trade Paperbacks

Summary

A black swan is an event, positive or negative, that is deemed improbable yet causes massive consequences. In this groundbreaking and prophetic book, Taleb shows in a playful way that Black Swan events explain almost everything about our world, and yet we-especially the experts-are blind to them. In this second edition, Taleb has added a new essay,On Robustness and Fragility, which offers tools to navigate and exploit a Black Swan world. *2nd Edition, With a new essay: "On Robustness and Fragility"

Author Biography

Nassim Nicholas Taleb has devoted his life to immersing himself in problems of luck, uncertainty, probability, and knowledge. Part literary essayist, part empiricist, part no-nonsense mathematical trader, he is currently taking a break as Dean’s Professor in the Sciences of Uncertainty at the University of Massachusetts at Amherst. His last book, the bestseller Fooled by Randomness, has been published in nineteen languages. Taleb lives mostly in New York.


From the Hardcover edition.

Excerpts

PROLOGUE

ON THE PLUMAGE OF BIRDS

Before the discovery of Australia, people in the old world were convinced thatallswans were white, an unassailable belief as it seemed completely confirmed by empirical evidence. The sighting of the first black swan might have been an interesting surprise for a few ornithologists (and others extremely concerned with the coloring of birds), but that is not where the significance of the story lies. It illustrates a severe limitation to our learning from observations or experience and the fragility of our knowledge. One single observation can invalidate a general statement derived from millennia of confirmatory sightings of millions of white swans. All you need is one single (and, I am told, quite ugly) black bird.*

I push one step beyond this philosophical-logical question into an empirical reality, and one that has obsessed me since childhood. What we call here a Black Swan (and capitalize it) is an event with the following three attributes.

First, it is anoutlier,as it lies outside the realm of regular expectations, because nothing in the past can convincingly point to its possibility. Second, it carries an extreme impact. Third, in spite of its outlier status, human nature makes us concoct explanations for its occurrenceafterthe fact, making it explainable and predictable.

I stop and summarize the triplet: rarity, extreme impact, and retrospective (though not prospective) predictability.* A small number of Black Swans explain almost everything in our world, from the success of ideas and religions, to the dynamics of historical events, to elements of our own personal lives. Ever since we left the Pleistocene, some ten millennia ago, the effect of these Black Swans has been increasing. It started accelerating during the industrial revolution, as the world started getting more complicated, while ordinary events, the ones we study and discuss and try to predict from reading the newspapers, have become increasingly inconsequential.

Just imagine how little your understanding of the world on the eve of the events of 1914 would have helped you guess what was to happen next. (Don’t cheat by using the explanations drilled into your cranium by your dull high school teacher). How about the rise of Hitler and the subsequent war? How about the precipitous demise of the Soviet bloc? How about the rise of Islamic fundamentalism? How about the spread of the Internet? How about the market crash of 1987 (and the more unexpected recovery)? Fads, epidemics, fashion, ideas, the emergence of art genres and schools. All follow these Black Swan dynamics. Literally, just about everything of significance around you might qualify.

This combination of low predictability and large impact makes the Black Swan a great puzzle; but that is not yet the core concern of this book. Add to this phenomenon the fact that we tend to act as if it does not exist! I don’t mean just you, your cousin Joey, and me, but almost all “social scientists” who, for over a century, have operated under the false belief that their tools could measure uncertainty. For the applications of the sciences of uncertainty to real-world problems has had ridiculous effects; I have been privileged to see it in finance and economics. Go ask your portfolio manager for his definition of “risk,” and odds are that he will supply you with ameasurethatexcludesthe possibility of the Black Swan–hence one that has no better predictive value for assessing the total risks than astrology (we will see how they dress up the intellectual fraud with mathematics). This problem is endemic in social matters.

The central idea of this book concerns our blindness with respect to randomness, particularly the large deviations: Why do we, scientists or nonscientists, hotshots or regular Joes, tend to see the pennies instead of the dollars? Wh

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Excerpted from The Black Swan: The Impact of the Highly Improbable by Nassim Nicholas Taleb
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