by Nassim Nicholas Taleb.

Random House. 368 pages. $26.95

BY JOHN J. MONAGHAN JR.
Special to the Journal

Nassim Nicolas Taleb is not an ornithologist. He is a self-confessed “statistician/philosopher/trader” with — a reader will conclude — the emphasis on philosopher. So his treatise is not of or for the birds; the point of the title is that most of the civilized world believed all swans were white until they discovered that in Australia, swans are black.

The point is, the black swan burst upon civilization as an improbability. Things had gone along swimmingly until, oops, there’s a black one. Improbable. Taleb gives this example: A turkey is raised in a farm yard, day after day for 1,000 days getting his feed and his water; life is good, life is predictable, life will likely continue thus forever. Until along comes one November Thursday. Improbable, thinks the turkey. Thanksgiving is the turkey’s black swan, his improbable. Things aren’t supposed to happen, but they do.

What makes this a cut above treatises of some so-called thinkers is Taleb himself. Of Lebanese birth (he tells of the Civil War there), he was a math whiz as a youth. His life has centered on luck, uncertainty, probability and knowledge, while working as a derivatives trader on Wall Street and in the Chicago pits (he has little good to say about that), a teacher at the Courant Institute of Mathematical Sciences at NYU, and currently as dean’s professor in the sciences of uncertainty at UMass Amherst. His pet philosopher is Hume.

Taleb has written, he says, as “a practitioner whose principal aim is not to be a sucker in things that matter, period.” He writes of high impact-low probability events (big banks go bust) and he doubts that one can learn from the past.

Not all Black Swans are bad. But, he says, “in general, positive Black Swans take time to show their effect while negative ones happen very quickly — it is much easier and much faster to destroy than to build.”

He lists five themes which, he says, arise from our “blindness to the Black Swan,” and which, in essence, are the same. We focus on pre-selected segments of the seen and generalize from it to the unseen (an error of confirmation), we fool ourselves with stories that cater to our Platonic thirst for distinct patterns (the narrative fallacy), we behave as if the Black Swan does not exist (human nature is not programmed for Black Swans), what we see is not necessarily what is there (history hides Black Swans from us), and we focus on a few well-defined sources at the expense of others that do not come easily to mind (we tunnel).

He also asserts a “triplet of opacity,” ailments that afflict the mind when it comes into contact with history: the illusion of understanding (everyone thinks he knows what’s going on in a complex — or random — world); the retrospective distortion (seeing history as a rear-view mirror), and the overvaluation of factual information (the handicap of authoritative and learned people).

Now if there’s an evident failing, it’s that Taleb bogs down in anecdotal material. He hashes and rehashes and wanders far afield in making a point until a reader yells, “Enough! Move on.”

Still, his thinking is definitely worth a look. Whether you finally decide what he advances is credo or crock, he will have made you think and rethink some or many concepts you have always accepted as gospel.

But you may be left wondering whether you have plowed through 368 pages of profundity and erudition that distill down to what you learned in the Army a half century earlier: excrement happens.