Antifragile: Things That Gain from Disorder by Nassim Nicholas Taleb


RATING: 9/10

How to benefit from risk and uncertainty (Black Swan events) by making yourself what Taleb calls Antifragile. A great book espousing the virtues of partaking in opportunities with more upside than downside, becoming a doer versus academic theorizer, and living a simple, but robust life. The book is a lot to take in and feels rant-y, but has deeply altered my thinking.

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Let me be more aggressive: we are largely better at doing than we are at thinking, thanks to antifragility. I’d rather be dumb and antifragile than extremely smart and fragile, any time.

The rarer the event, the less tractable, and the less we know about how frequent its occurrence—yet the rarer the event, the more confident these “scientists” involved in predicting, modeling, and using PowerPoint in conferences with equations in multicolor background have become.

Technology is the result of antifragility, exploited by risk-takers in the form of tinkering and trial and error, with nerd-driven design confined to the backstage. Engineers and tinkerers develop things while history books are written by academics; we will have to refine historical interpretations of growth, innovation, and many such things.

The fragilista belongs to that category of persons who are usually in suit and tie, often on Fridays; he faces your jokes with icy solemnity, and tends to develop back problems early in life from sitting at a desk, riding airplanes, and studying newspapers. He is often involved in a strange ritual, something commonly called “a meeting.” Now, in addition to these traits, he defaults to thinking that what he doesn’t see is not there, or what he does not understand does not exist. At the core, he tends to mistake the unknown for the nonexistent.

The Arabs have an expression for trenchant prose: no skill to understand it, mastery to write it.

It does not mean that one’s personal experiences constitute a sufficient sample to derive a conclusion about an idea; it is just that one’s personal experience gives the stamp of authenticity and sincerity of opinion. Experience is devoid of the cherry-picking that we find in studies, particularly those called “observational,” ones in which the researcher finds past patterns, and, thanks to the sheer amount of data, can therefore fall into the trap of an invented narrative.

Further, in writing, I feel corrupt and unethical if I have to look up a subject in a library as part of the writing itself. This acts as a filter—it is the only filter. If the subject is not interesting enough for me to look it up independently, for my own curiosity or purposes, and I have not done so before, then I should not be writing about it at all, period. It does not mean that libraries (physical and virtual) are not acceptable; it means that they should not be the source of any idea. Students pay to write essays on topics for which they have to derive knowledge from a library as a self-enhancement exercise; a professional who is compensated to write and is taken seriously by others should use a more potent filter. Only distilled ideas, ones that sit in us for a long time, are acceptable—and those that come from reality. It is time to revive the not well-known philosophical notion of doxastic commitment, a class of beliefs that go beyond talk, and to which we are committed enough to take personal risks.

If you see fraud and do not say fraud, you are a fraud.

many writers and scholars speak in private, say, after half a bottle of wine, differently from the way they do in print. Their writing is certifiably fake, fake. And many of the problems of society come from the argument “other people are doing it.” So if I call someone a dangerous ethically challenged fragilista in private after the third glass of Lebanese wine (white), I will be obligated to do so here.

A man is morally free when … he judges the world, and judges other men, with uncompromising sincerity. This is not just an aim but an obligation.

academics (particularly in social science) seem to distrust each other; they live in petty obsessions, envy, and icy-cold hatreds, with small snubs developing into grudges, fossilized over time in the loneliness of the transaction with a computer screen and the immutability of their environment. Not to mention a level of envy I have almost never seen in business.…

I call them books rather than sections or parts. Books to me are not expanded journal articles, but reading experiences; and the academics who tend to read in order to cite in their writing—rather than read for enjoyment, curiosity, or simply because they like to read—tend to be frustrated when they can’t rapidly scan the text and summarize it in one sentence that connects it to some existing discourse in which they have been involved.

If you want to become antifragile, put yourself in the situation “loves mistakes”—to the right of “hates mistakes”—by making these numerous and small in harm. We will call this process and approach the “barbell” strategy.

Gladstone was impressive in many respects. Aside from his erudition, force of character, respect for the weak, and high level of energy, four very attractive attributes (respect for the weak being, after intellectual courage, the second most attractive quality to this author), he showed remarkable prescience.

The excess energy released from overreaction to setbacks is what innovates!

Undercompensation from the absence of a stressor, inverse hormesis, absence of challenge, degrades the best of the best.

Psychologists have shown the irony of the process of thought control: the more energy you put into trying to control your ideas and what you think about, the more your ideas end up controlling you.

if you really want people to read a book, tell them it is “overrated,” with a sense of outrage (and use the attribute “underrated” for the opposite effect).

So here is a simple rule of thumb (a heuristic): to estimate the quality of research, take the caliber of the highest detractor, or the caliber of the lowest detractor whom the author answers in print—whichever is lower.

You do not want to “control” your reputation; you won’t be able to do it by controlling information flow. Instead, focus on altering your exposure, say, by putting yourself in a position impervious to reputational damage. Or even put yourself in a situation to benefit from the antifragility of information.

With few exceptions, those who dress outrageously are robust or even antifragile in reputation; those clean-shaven types who dress in suits and ties are fragile to information about them.

somehow it is only when you don’t care about your reputation that you tend to have a good one. Just as in matters of seduction, people lend the most to those who need them the least.

So I end this section with a thought. It is quite perplexing that those from whom we have benefited the most aren’t those who have tried to help us (say with “advice”) but rather those who have actively tried—but eventually failed—to harm us.

Humans tend to do better with acute than with chronic stressors, particularly when the former are followed by ample time for recovery, which allows the stressors to do their jobs as messengers.

There exist the kind of people for whom life is some kind of project. After talking to them, you stop feeling good for a few hours; life starts tasting like food cooked without salt.

Ancestral life had no homework, no boss, no civil servants, no academic grades, no conversation with the dean, no consultant with an MBA, no table of procedure, no application form, no trip to New Jersey, no grammatical stickler, no conversation with someone boring you: all life was random stimuli and nothing, good or bad, ever felt like work. Dangerous, yes, but boring, never.

The fragility of every startup is necessary for the economy to be antifragile, and that’s what makes, among other things, entrepreneurship work: the fragility of We can simplify the relationships between fragility, errors, and antifragility as follows. When you are fragile, you depend on things following the exact planned course, with as little deviation as possible—for deviations are more harmful than helpful.

Had the Titanic not had that famous accident, as fatal as it was, we would have kept building larger and larger ocean liners and the next disaster would have been even more tragic. So the people who perished were sacrificed for the greater good; they unarguably saved more lives than were lost.

Further, my characterization of a loser is someone who, after making a mistake, doesn’t introspect, doesn’t exploit it, feels embarrassed and defensive rather than enriched with a new piece of information, and tries to explain why he made the mistake rather than moving on. These types often consider themselves the “victims” of some large plot, a bad boss, or bad weather.

Every time you use a coffeemaker for your morning cappuccino, you are benefiting from the fragility of the coffeemaking entrepreneur who failed. He failed in order to help put the superior merchandise on your kitchen counter.

Now, by disrupting the model, as we will see, with bailouts, governments typically favor a certain class of firms that are large enough to require being saved in order to avoid contagion to other business. This is the opposite of healthy risk-taking; it is transferring fragility from the collective to the unfit. People have difficulty realizing that the solution is building a system in which nobody’s fall can drag others down—for continuous failures work to preserve the system. Paradoxically, many government interventions and social policies end up hurting the weak and consolidating the established.

Nietzsche’s famous expression “what does not kill me makes me stronger” can be easily misinterpreted as meaning Mithridatization or hormesis. It may be one of these two phenomena, very possible, but it could as well mean “what did not kill me did not make me stronger, but spared me because I am stronger than others; but it killed others and the average population is now stronger because the weak are gone.” In other words, I passed an exit exam.

These pre-death terrorists get into a mood similar to an ecstatic trance in which their emotions drive them to become indifferent to their own mortality. It is a fallacy that suicide bombers are driven by the promise of a reward of some Islamic paradise with virgins and other entertainment, for, as the anthropologist Scott Atran has pointed out, the first suicide bombers in the Levant were revolutionaries of Greek Orthodox background—my tribe—not Islamists.

I am an ingrate toward the man whose overconfidence caused him to open a restaurant and fail, enjoying my nice meal while he is probably eating canned tuna.

there is no such thing as a failed entrepreneur or failed scientific researcher, any more than there is a successful babbler, philosophaster, commentator, consultant, lobbyist, or business school professor who does not take personal risks.

It is often with the most noble intentions that we do so, as we are pressured to “fix” things, so we often blow them up with our fear of randomness and love of smoothness.

Artisans, say, taxi drivers, prostitutes (a very, very old profession), carpenters, plumbers, tailors, and dentists, have some volatility in their income but they are rather robust to a minor professional Black Swan, one that would bring their income to a complete halt. Their risks are visible. Not so with employees, who have no volatility, but can be surprised to see their income going to zero after a phone call from the personnel department. Employees’ risks are hidden.

A week with declining earnings for a taxi driver or a prostitute provides information concerning the environment and intimates the need to find a new part of town where clients hang around; a month or so without earnings drives them to revise their skills.

A point worth repeating every time it applies, this avoidance of small mistakes makes the large ones more severe.

The centralized state resembles the income of John; the city-state model that of George.

On a large scale, others are abstract items; given the lack of social contact with the people concerned, the civil servant’s brain leads rather than his emotions—with numbers, spreadsheets, statistics, more spreadsheets, and theories.

“We people of Aleppo prefer war to prison.” I thought that he meant that they were going to put him in jail, but then I realized that by “prison” he meant the loss of political and economic freedoms.

Some people have fallen for the naive turkey-style belief that the world is getting safer and safer, and of course they naively attribute it to the holy “state” (though bottom-up Switzerland has about the lowest rate of violence of any place on the planet). It is exactly like saying that nuclear bombs are safer because they explode less often. The world is subjected to fewer and fewer acts of violence, while wars have the potential to be more criminal. We were very close to the mother of all catastrophes in the 1960s when the United States was about to pull the nuclear trigger on the Soviet Union. Very close. When we look at risks in Extremistan, we don’t look at evidence (evidence comes too late), we look at potential damage: never has the world been more prone to more damage; never.6 It is hard to explain to naive data-driven people that risk is in the future, not in the past.

Indeed, confusing people a little bit is beneficial—it is good for you and good for them. For an application of the point in daily life, imagine someone extremely punctual and predictable who comes home at exactly six o’clock every day for fifteen years. You can use his arrival to set your watch. The fellow will cause his family anxiety if he is barely a few minutes late. Someone with a slightly more volatile—hence unpredictable—schedule, with, say, a half-hour variation, won’t do so.

By a mechanism called stochastic resonance, adding random noise to the background makes you hear the sounds (say, music) with more accuracy.

What is plaguing us in the United States is not the two-party system, but being stuck with the same two parties. Parties don’t have organic built-in expiration dates.

Take rotten governments like the one in Egypt before the riots of 2011, supported by the United States for four decades in order “to avoid chaos,” with the side effect of a coterie of privileged pillagers using superpowers as a backstop—identical to bankers using their “too big to fail” status to scam taxpayers and pay themselves high bonuses.

Few people are aware of the fact that the bitterness of Iranians toward the United States comes from the fact that the United States—a democracy—installed a monarch, the repressive Shah of Iran, who pillaged the place but gave the United States the “stability” of access to the Persian Gulf. The theocratic regime in Iran today is largely the result of such repression. We need to learn to think in second steps, chains of consequences, and side effects.

Time for American policy makers to understand that the more they intervene in other countries for the sake of stability, the more they bring instability (except for emergency-room-style cases).

We are moving into a phase of modernity marked by the lobbyist, the very, very limited liability corporation, the MBA, sucker problems, secularization (or rather reinvention of new sacred values like flags to replace altars), the tax man, fear of the boss, spending the weekend in interesting places and the workweek in a putatively less interesting one, the separation of “work” and “leisure” (though the two would look identical to someone from a wiser era), the retirement plan, argumentative intellectuals who would disagree with this definition of modernity, literal thinking, inductive inference, philosophy of science, the invention of social science, smooth surfaces, and egocentric architects. Violence is transferred from individuals to states. So is financial indiscipline. At the center of all this is the denial of antifragility.

Remember that you need a name for the color blue when you build a narrative, but not in action—the thinker lacking a word for “blue” is handicapped; not the doer. (I’ve had a hard time conveying to intellectuals the intellectual superiority of practice.)

Modernity widened the difference between the sensational and the relevant—in a natural environment the sensational is, well, sensational for a reason; today we depend on the press for such essentially human things as gossip and anecdotes and we care about the private lives of people in very remote places.

Medical error still currently kills between three times (as accepted by doctors) and ten times as many people as car accidents in the United States.

It is generally accepted that harm from doctors—not including risks from hospital social science seems to diverge from theory to theory. During the cold war, the University of Chicago was promoting laissez-faire theories, while the University of Moscow taught the exact opposite—but their respective physics departments were in convergence, if not total agreement. This is the reason I put social science theories in the left column of the Triad, as something superfragile for real-world decisions and unusable for risk analyses. The very designation “theory” is even upsetting. In social science we should call these constructs “chimeras” rather than theories.

Why should I try to fool people by writing about a subject for which I feel no natural drive?

Using my ecological reasoning, someone who procrastinates is not irrational; it is his environment that is irrational. And the psychologist or economist calling him irrational is the one who is beyond irrational.

A very rarely discussed property of data: it is toxic in large quantities—even in moderate quantities.

The best solution is to only look at very large changes in data or conditions, never at small ones.

People are still under the illusion that “science” means more data.

In the United States, we burn twelve calories in transportation for every calorie of nutrition; in Soviet Russia, it was one to one.

How could we have the happiest nation in the world, Denmark (assuming “happiness” is both measurable and desirable), and a monstrously large state?

Winner-take-all effects are worsening: success for an author, a company, an idea, a musician, an athlete is planetary, or nothing. These worsen predictability since almost everything in socioeconomic life now is dominated by Black Swans. Our sophistication continuously puts us ahead of ourselves, creating things we are less and less capable of understanding.

A man is honorable in proportion to the personal risks he takes for his opinion—in other words, the amount of downside he is exposed to.

Fat Tony’s model is quite simple. He identifies fragilities, makes a bet on the collapse of the fragile unit, lectures Nero and trades insults with him about sociocultural matters, reacts to Nero’s jabs at New Jersey life, collects big after the collapse. Then he has lunch.

To become a successful philosopher king, it is much better to start as a king than as a philosopher.

When you become rich, the pain of losing your fortune exceeds the emotional gain of getting additional wealth, so you start living under continuous emotional threat.

Dependence on circumstances—rather, the emotions that arise from circumstances—induces a form of slavery.

It is hard to stick to a good discipline of mental write-off when things are going well, yet that’s when one needs the discipline the most.

Stoicism is about the domestication, not necessarily the elimination, of emotions. It is not about turning humans into vegetables. My idea of the modern Stoic sage is someone who transforms fear into prudence, pain into information, mistakes into initiation, and desire into undertaking.

And professions can be serial: something very safe, then something speculative. A friend of mine built himself a very secure profession as a book editor, in which he was known to be very good. Then, after a decade or so, he left completely for something speculative and highly risky. This is a true barbell in every sense of the word: he can fall back on his previous profession should the speculation fail, or fail to bring the expected satisfaction.

Seneca elected to do: he initially had a very active, adventurous life, followed by a philosophical withdrawal to write and meditate, rather than a “middle” combination of both. Many of the “doers” turned “thinkers” like Montaigne have done a serial barbell: pure action, then pure reflection.

Georges Simenon, one of the most prolific writers of the twentieth century, only wrote sixty days a year, with three hundred days spent “doing nothing.” He published more than two hundred novels.

More barbells. Do crazy things (break furniture once in a while), like the Greeks during the later stages of a drinking symposium, and stay “rational” in larger decisions. Trashy gossip magazines and classics or sophisticated works; never middlebrow stuff. Talk to either undergraduate students, cab drivers, and gardeners or the highest caliber scholars; never to middling-but-career-conscious academics. If you dislike someone, leave him alone or eliminate him; don’t attack him verbally.

Never ask people what they want, or where they want to go, or where they think they should go, or, worse, what they think they will desire tomorrow. The strength of the computer entrepreneur Steve Jobs was precisely in distrusting market research and focus groups—those based on asking people what they want—and following his own imagination. His modus was that people don’t know what they want until you provide them with it.

The worst side effect of wealth is the social associations it forces on its victims, as people with big houses tend to end up socializing with other people with big houses. Beyond a certain level of opulence and independence, gents tend to be less and less personable and their conversation less and less interesting.

Antifragility equals more to gain than to lose equals more upside than downside equals asymmetry (favorable) equals likes volatility.

The option I am talking about is no different from what we call options in daily life—the vacation resort with the most options is more likely to provide you with the activity that satisfies your tastes, and the one with the narrowest choices is likely to fail. So you need less information, that is, less knowledge, about the resort with broader options.

You need to know whether you do not like the pursuit of money and wealth because you genuinely do not like it, or because you are rationalizing your inability to be successful at it with the argument that wealth is not a good thing because it is bad for one’s digestive system or disturbing for one’s sleep or other such arguments.

Options, any options, by allowing you more upside than downside, are vectors of antifragility.

Beyond books, consider this simple heuristic: your work and ideas, whether in politics, the arts, or other domains, are antifragile if, instead of having one hundred percent of the people finding your mission acceptable or mildly commendable, you are better off having a high percentage of people disliking you and your message (even intensely), combined with a low percentage of extremely loyal and enthusiastic supporters. Options like dispersion of outcomes and don’t care about the average too much.

No one at present dares to state the obvious: growth in society may not come from raising the average the Asian way, but from increasing the number of people in the “tails,” that small, very small number of risk takers crazy enough to have ideas of their own, those endowed with that very rare ability called imagination, that rarer quality called courage, and who make things happen.

Steve Jobs at a famous speech: “Stay hungry, stay foolish.” He probably meant “Be crazy but retain the rationality of choosing the upper bound when you see it.”

Option = asymmetry + rationality

The largest generators of wealth in America historically have been, first, real estate (investors have the option at the expense of the banks), and, second, technology (which relies almost completely on trial and error). Further, businesses with negative optionality (that is, the opposite of having optionality) such as banking have had a horrible performance through history: banks lose periodically every penny made in their history thanks to blowups.

Just as great geniuses invent their predecessors, practical innovations create their theoretical ancestry.

Both governments and universities have done very, very little for innovation and discovery, precisely because, in addition to their blinding rationalism, they look for the complicated, the lurid, the newsworthy, the narrated, the scientistic, and the grandiose, rarely for the wheel on the suitcase. Simplicity, I realized, does not lead to laurels.

As I keep saying, removal of something non-natural does not carry long-term side effects; it is typically iatrogenics-free.

Academia is well equipped to tell us what it did for us, not what it did not—hence how indispensable its methods are.

Serious empirical investigation (largely thanks to one Lant Pritchet, then a World Bank economist) shows no evidence that raising the general level of education raises income at the level of a country. But we know the opposite is true, that wealth leads to the rise of education—not an optical illusion.

Entrepreneurs are selected to be just doers, not thinkers, and doers do, they don’t talk, and it would be unfair, wrong, and downright insulting to measure them in the talk department. The same with artisans: the quality lies in their product, not their conversation—in fact they can easily have false beliefs that, as a side effect (inverse iatrogenics), lead them to make better products, so what?

Bureaucrats, on the other hand, because of the lack of an objective metric of success and the absence of market forces, are selected on the “halo effects” of shallow looks and elegance. The side effect is to make them better at conversation.

So I saw the less is more in action: the more studies, the less obvious elementary but fundamental things become; activity, on the other hand, strips things to their simplest possible model.

Nobody worries that a child ignorant of the various theorems of aerodynamics and incapable of solving an equation of motion would be unable to ride a bicycle.

Practitioners don’t write; they do. Birds fly and those who lecture them are the ones who write their story. So it is easy to see that history is truly written by losers with time on their hands and a protected academic position.

instead of looking into a scholar’s writings to see whether he is credible or not, it is always best to consider what his detractors say—they will uncover what’s worst in his argument.

Much of all of this is a religious belief in the unconditional power of organized science, one that has replaced unconditional religious belief in organized religion.

Private industry develops nine drugs out of ten. Even the tax-funded National Institutes of Health found that out of forty-six drugs on the market with significant sales, about three had anything to do with federal funding.

We have not digested the fact that cures for cancer had been coming from other branches of research. You search for noncancer drugs (or noncancer nondrugs) and find something you were not looking for (and vice versa).

For an illustration of business drift, rational and opportunistic business drift, take the following. Coca-Cola began as a pharmaceutical product. Tiffany & Co., the fancy jewelry store company, started life as a stationery store. The last two examples are close, perhaps, but consider next: Raytheon, which made the first missile guidance system, was a refrigerator maker (one of the founders was no other than Vannevar Bush, who conceived the teleological linear model of science we saw earlier; go figure). Now, worse: Nokia, who used to be the top mobile phone maker, began as a paper mill (at some stage they were into rubber shoes). DuPont, now famous for Teflon nonstick cooking pans, Corian countertops, and the durable fabric Kevlar, actually started out as an explosives company. Avon, the cosmetics company, started out in door-to-door book sales. And, the strangest of all, Oneida Silversmiths was a community religious cult but for regulatory reasons they needed to use as cover a joint stock company.

I have a simple rule, that those who teach at Harvard should be expected to have much less understanding of things than cab drivers or people innocent of canned methods of inference.

Let me stop to issue rules based on the chapter so far. (i) Look for optionality; in fact, rank things according to optionality, (ii) preferably with open-ended, not closed-ended, payoffs; (iii) Do not invest in business plans but in people, so look for someone capable of changing six or seven times over his career, or more (an idea that is part of the modus operandi of the venture capitalist Marc Andreessen); one gets immunity from the backfit narratives of the business plan by investing in people. It is simply more robust to do so; (iv) Make sure you are barbelled, whatever that means in your business.

Formal thinkers and theorizing theorizers tend to write books; seat-of-the-pants people tend to be practitioners who are often content to get the excitement, make or lose the money, and discourse at the pub. Their experiences are often formalized by academics; indeed, history has been written by those who want you to believe that reasoning has a monopoly or near monopoly on the production of knowledge.

Formalists, to protect their turf, have always played on the logical fallacy that if quacks are found among nonacademics, nonacademics are all quacks. They keep doing it: the statement all that is nonrigorous is nonacademic (assuming one is a sucker and believes it) does not imply that all that is nonacademic is nonrigorous.

As a child of civil war, I disbelieve in structured learning—actually I believe that one can be an intellectual without being a nerd, provided one has a private library instead of a classroom, and spends time as an aimless (but rational) flâneur benefiting from what randomness can give us inside and outside the library. Provided we have the right type of rigor, we need randomness, mess, adventures, uncertainty, self-discovery, near-traumatic episodes, all these things that make life worth living, compared to the structured, fake, and ineffective life of an empty-suit CEO with a preset schedule and an alarm clock.

The trick is to be bored with a specific book, rather than with the act of reading.

It was a barbell—play it safe at school and read on your own, have zero expectation from school.

There is such a thing as nonnerdy applied mathematics: find a problem first, and figure out the math that works for it (just as one acquires language), rather than study in a vacuum through theorems and artificial examples, then change reality to make it look like these examples.

Much of what other people know isn’t worth knowing.

What one needs to know for a profession, is necessarily what lies outside the corpus, as far away from the center as possible.

Socrates’ technique was to make his interlocutor, who started with a thesis, agree to a series of statements, then proceed to show him how the statements he agreed to are inconsistent with the original thesis, thus establishing that he has no clue as to what he was taking about.

He taught Nero that an answer is planted in every question; never respond with a straight answer to a question that makes no sense to you.

“My dear Socrates … you know why they are putting you to death? It is because you make people feel stupid for blindly following habits, instincts, and traditions. You may be occasionally right. But you may confuse them about things they’ve been doing just fine without getting in trouble. You are destroying people’s illusions about themselves. You are taking the joy of ignorance out of the things we don’t understand. And you have no answer; you have no answer to offer them.”

Perhaps—thus he [Socrates] should have asked himself—what is not intelligible to me is not necessarily unintelligent? Perhaps there is a realm of wisdom from which the logician is exiled?

Logic excludes—by definition—nuances, and since truth resides exclusively in the nuances, it is “a useless instrument for finding Truth in the moral and political sciences.”

For Tony, the distinction in life isn’t True or False, but rather sucker or nonsucker. Things are always simpler with him. In real life, as we saw with the ideas of Seneca and the bets of Thales, exposure is more important than knowledge; decision effects supersede logic. Textbook “knowledge” misses a dimension, the hidden asymmetry of benefits—just like the notion of average. The need to focus on the payoff from your actions instead of studying the structure of the world (or understanding the “True” and the “False”) has been largely missed in intellectual history.

Philosophers talk about truth and falsehood. People in life talk about payoff, exposure, and consequences (risks and rewards), hence fragility and antifragility. And sometimes philosophers and thinkers and those who study conflate Truth with risks and rewards.

You decide principally based on fragility, not probability. Or to rephrase, You decide principally based on fragility, not so much on True/False.

For the fragile, the cumulative effect of small shocks is smaller than the single effect of an equivalent single large shock.

For the antifragile, shocks bring more benefits (equivalently, less harm) as their intensity increases (up to a point).

If you double the exposure to something, do you more than double the harm it will cause? If so, then this is a situation of fragility. Otherwise, you are robust.

Another aspect of size: large corporations also end up endangering neighborhoods. I’ve used the following argument against large superstore chains in spite of the advertised benefits. A large super-megastore wanted to acquire an entire neighborhood near where I live, causing uproar owing to the change it would bring to the character of the neighborhood. The argument in favor was the revitalization of the area, that type of story. I fought the proposal on the following grounds: should the company go bust (and the statistical elephant in the room is that it eventually will), we would end up with a massive war zone. This is the type of argument the British advisors Rohan Silva and Steve Hilton have used in favor of small merchants, along the poetic “small is beautiful.” It is completely wrong to use the calculus of benefits without including the probability of failure.

I have used all my life a wonderfully simple heuristic: charlatans are recognizable in that they will give you positive advice, and only positive advice, exploiting our gullibility and sucker-proneness for recipes that hit you in a flash as just obvious, then evaporate later as you forget them.

In practice it is the negative that’s used by the pros, those selected by evolution: chess grandmasters usually win by not losing; people become rich by not going bust (particularly when others do); religions are mostly about interdicts; the learning of life is about what to avoid. You reduce most of your personal risks of accident thanks to a small number of measures.

Being fooled by randomness is that in most circumstances fraught with a high degree of randomness, one cannot really tell if a successful person has skills, or if a person with skills will succeed—but we can pretty much predict the negative, that a person totally devoid of skills will eventually fail.

So the central tenet of the epistemology I advocate is as follows: we know a lot more what is wrong than what is right, or, phrased according to the fragile/robust classification, negative knowledge (what is wrong, what does not work) is more robust to error than positive knowledge (what is right, what works).

knowledge grows by subtraction much more than by addition—given that what we know today might turn out to be wrong but what we know to be wrong cannot turn out to be right, at least not easily.

Since one small observation can disprove a statement, while millions can hardly confirm it, disconfirmation is more rigorous than confirmation.

For the bad guy can cause more harm than the collective actions of good ones.

Bentham’s idea that “the art of the legislator is limited to the prevention of everything that might prevent the development of their [members of the assembly] liberty and their intelligence.”

Keeping one’s distance from an ignorant person is equivalent to keeping company with a wise man.

Steve Jobs: “People think focus means saying yes to the thing you’ve got to focus on. But that’s not what it means at all. It means saying no to the hundred other good ideas that there are. You have to pick carefully. I’m actually as proud of the things we haven’t done as the things I have done. Innovation is saying no to 1,000 things.”

Few realize that we are moving into the far more uneven distribution of 99/1 across many things that used to be 80/20: 99 percent of Internet traffic is attributable to less than 1 percent of sites, 99 percent of book sales come from less than 1 percent of authors … and I need to stop because numbers are emotionally stirring. Almost everything contemporary has winner-take-all effects, which includes sources of harm and benefits.

For instance, a small number of homeless people cost the states a disproportionate share of the bills, which makes it obvious where to look for the savings. A small number of employees in a corporation cause the most problems, corrupt the general attitude—and vice versa—so getting rid of these is a great solution. A small number of customers generate a large share of the revenues. I get 95 percent of my smear postings from the same three obsessive persons, all representing the same prototypes of failure.

When it comes to health care, Ezekiel Emanuel showed that half the population accounts for less than 3 percent of the costs, with the sickest 10 percent consuming 64 percent of the total pie.

For instance, if you have more than one reason to do something (choose a doctor or veterinarian, hire a gardener or an employee, marry a person, go on a trip), just don’t do it. It does not mean that one reason is better than two, just that by invoking more than one reason you are trying to convince yourself to do something. Obvious decisions (robust to error) require no more than a single reason.

I have often followed what I call Bergson’s razor: “A philosopher should be known for one single idea, not more”

when I am told that someone has three hundred academic papers and twenty-two honorary doctorates, but no other single compelling contribution or main idea behind it, I avoid him like the bubonic plague.

Odds are that your imagination will be adding things to the present world. I am sorry, but I will show in this chapter that this approach is exactly backward: the way to do it rigorously, according to the notions of fragility and antifragility, is to take away from the future, reduce from it, simply, things that do not belong to the coming times. Via negativa. What is fragile will eventually break; and, luckily, we can easily tell what is fragile. Positive Black Swans are more unpredictable than negative ones.

Your error rate for a ten-year forecast of, say, the sales of a computer plant or the profits of a commodity vendor can be a thousand times that of a one-year projection.

David Edgerton showed that in the early 2000s we produce two and a half times as many bicycles as we do cars and invest most of our technological resources in maintaining existing equipment or refining old technologies (note that this is not just a Chinese phenomenon: Western cities are aggressively trying to become bicycle-friendly).

Technothinkers tend to have an “engineering mind”—to put it less politely, they have autistic tendencies. While they don’t usually wear ties, these types tend, of course, to exhibit all the textbook characteristics of nerdiness—mostly lack of charm, interest in objects instead of persons, causing them to neglect their looks. They love precision at the expense of applicability. And they typically share an absence of literary culture.

This absence of literary culture is actually a marker of future blindness because it is usually accompanied by a denigration of history, a byproduct of unconditional neomania. Outside of the niche and isolated genre of science fiction, literature is about the past. We do not learn physics or biology from medieval textbooks, but we still read Homer, Plato, or the very modern Shakespeare.

Technology is at its best when it is invisible. I am convinced that technology is of greatest benefit when it displaces the deleterious, unnatural, alienating, and, most of all, inherently fragile preceding technology.

And the great use of the tablet computer (notably the iPad) is that it allows us to return to Babylonian and Phoenician roots of writing and take notes on a tablet (which is how it started). One can now jot down handwritten, or rather fingerwritten, notes—it is much more soothing to write longhand, instead of having to go through the agency of a keyboard.

For the perishable, every additional day in its life translates into a shorter additional life expectancy. For the nonperishable, every additional day may imply a longer life expectancy.

Every year that passes without extinction doubles the additional life expectancy.4 This is an indicator of some robustness. The robustness of an item is proportional to its life!

Gott made a list of Broadway shows on a given day, May 17, 1993, and predicted that the longest-running ones would last longest, and vice versa. He was proven right with 95 percent accuracy.

I am not saying that all technologies do not age, only that those technologies that were prone to aging are already dead.

someone who sells “futuristic” ideas will not make a lot of money selling the value of the past! New technology is easier to hype up.

Arabic proverb to that effect: he who does not have a past has no future.

We rely more on water than on cell phones but because water does not change and cell phones do, we are prone to thinking that cell phones play a larger role than they do. Second, because the new generations are more aggressive with technology, we notice that they try more things, but we ignore that these implementations don’t usually stick. Most “innovations” are failures, just as most books are flops, which should not discourage anyone from trying.

with so many technologically driven and modernistic items—skis, cars, computers, computer programs—it seems that we notice differences between versions rather than commonalities.

I have never heard anyone address the large differences between e-readers and physical books, like smell, texture, dimension (books are in three dimensions), color, ability to change pages, physicality of an object compared to a computer screen, and hidden properties causing unexplained differences in enjoyment. The focus of the discussion will be commonalities (how close to a book this wonderful device is). Yet when he compares his version of an e-reader to another e-reader, he will invariably focus on minute differences.

Almost everything built since World War II has an unnatural smoothness to it.

Again, we have the machine-organism dichotomy: to her the city is an organism, for Moses it is a machine to be improved upon.

Books that have been around for ten years will be around for ten more; books that have been around for two millennia should be around for quite a bit of time, and so forth.

Attending breakthrough conferences might be, statistically speaking, as much a waste of time as buying a mediocre lottery ticket, one with a small payoff. The odds of the paper’s being relevant—and interesting—in five years is no better than one in ten thousand. The fragility of science!

Unlike dilettantes, career professionals are to knowledge what prostitutes are to love.

A rule on what to read. “As little as feasible from the last twenty years, except history books that are not about the last fifty years,”

If something that makes no sense to you (say, religion—if you are an atheist—or some age-old habit or practice called irrational); if that something has been around for a very, very long time, then, irrational or not, you can expect it to stick around much longer, and outlive those who call for its demise.

Fat Tony’s don’t-be-a-sucker rule: the non-natural needs to prove its benefits, not the natural—according to the statistical principle outlined earlier that nature is to be considered much less of a sucker than humans. In a complex domain, only time—a long time—is evidence.

We should not take risks with near-healthy people; but we should take a lot, a lot more risks with those deemed in danger.

If the patient is close to death, all speculative treatments should be encouraged—no holds barred. Conversely, if the patient is near healthy, then Mother Nature should be the doctor.

Let me express my rule as follows: what Mother Nature does is rigorous until proven otherwise; what humans and science do is flawed until proven otherwise.

We are built to be dupes for theories. But theories come and go; experience stays. Explanations change all the time, and have changed all the time in history (because of causal opacity, the invisibility of causes) with people involved in the incremental development of ideas thinking they always had a definitive theory; experience remains constant.

The same holds for the statement Lifting weights increases your muscle mass. In the past they used to say that weight lifting caused the “micro-tearing of muscles,” with subsequent healing and increase in size.

Add neurosomething to a field, and suddenly it rises in respectability and becomes more convincing as people now have the illusion of a strong causal link—yet the brain is too complex for that; it is both the most complex part of the human anatomy and the one that seems most susceptible to sucker-causation.

If we live longer, it is thanks to medicine’s benefits in cases that are lethal, in which the condition is severe—hence low iatrogenics.

Modern happiness researchers (who usually look quite unhappy), often psychologists turned economists (or vice versa), do not use nonlinearities and convexity effects when they lecture us about happiness as if we knew what it was and whether that’s what we should be after. Instead, they should be lecturing us about unhappiness (I speculate that just as those who lecture on happiness look unhappy, those who lecture on unhappiness would look happy); the “pursuit of happiness” is not equivalent to the “avoidance of unhappiness.” Each of us certainly knows not only what makes us unhappy (for instance, copy editors, commuting, bad odors, pain, the sight of a certain magazine in a waiting room, etc.), but what to do about it.

I derived the rule that what is called “healthy” is generally unhealthy, just as “social” networks are antisocial, and the “knowledge”-based economy is typically ignorant.

When I see pictures of my friend the godfather of the Paleo ancestral lifestyle, Art De Vany, who is extremely fit in his seventies (much more than most people thirty years younger than him), and those of the pear-shaped billionaires Rupert Murdoch or Warren Buffett or others in the same age group, I am invariably hit with the following idea. If true wealth consists in worriless sleeping, clear conscience, reciprocal gratitude, absence of envy, good appetite, muscle strength, physical energy, frequent laughs, no meals alone, no gym class, some physical labor (or hobby), good bowel movements, no meeting rooms, and periodic surprises, then it is largely subtractive (elimination of iatrogenics).

We are not the first generation to believe that the worst possible thing to befall us is death. But for the ancients, the worst possible outcome was not death, but a dishonorable death, or even just a regular one. For a classical hero, dying in a retirement home with a rude nurse and a network of tubes coming into and out of your nose would not be the attractive telos for a life.

And, of course, we have this modern illusion that we should live as long as we can. As if we were each the end product. This idea of the “me” as a unit can be traced to the Enlightenment. And, with it, fragility.

Note that if I had to find the anti-me, the person with diametrically opposite ideas and lifestyle on the planet, it would be that Ray Kurzweil fellow. It is not just neomania. While I propose removing offensive elements from people’s diets (and lives), he works by adding, popping close to two hundred pills daily. Beyond that, these attempts at immortality leave me with deep moral revulsion.

A half-man (or, rather, half-person) is not someone who does not have an opinion, just someone who does not take risks for it.

Dignity is worth nothing unless you earn it, unless you are willing to pay a price for it.

If you take risks and face your fate with dignity, there is nothing you can do that makes you small; if you don’t take risks, there is nothing you can do that makes you grand, nothing. And when you take risks, insults by half-men (small men, those who don’t risk anything) are similar to barks by nonhuman animals: you can’t feel insulted by a dog.

Ralph Nader has a simple rule: people voting for war need to have at least one descendant (child or grandchild) exposed to combat. For the Romans, engineers needed to spend some time under.

If Fat Tony had an opinion, he felt he needed, for ethical reasons, to have a corresponding exposure. As they say in Bensonhurst, you got to do so if you have an opinion. Otherwise, you do not really have an opinion at all.

There is another central element of ancient Mediterranean ethics: Factum tacendo, crimen facias acrius: For Publilius Syrus, he who does not stop a crime is an accomplice. (I’ve stated my own version of this in the prologue, which needs to be reiterated: if you see fraud and don’t say fraud, you are a fraud.)

Never ask anyone for their opinion, forecast, or recommendation. Just ask them what they have—or don’t have—in their portfolio.

The psychologist Gerd Gigerenzer has a simple heuristic. Never ask the doctor what you should do. Ask him what he would do if he were in your place. You would be surprised at the difference.

To put in Fat Tony terms: suckers try to be right, nonsuckers try to make the buck, or: Suckers try to win arguments, nonsuckers try to win. To put it again in other words: it is rather a good thing to lose arguments.

it is not ideas that survive, but people who have the right ones, or societies that have the correct heuristics, or the ones, right or wrong, that lead them to do the good thing.

I believe that forcing researchers to eat their own cooking whenever possible solves a serious problem in science. Take this simple heuristic—does the scientific researcher whose ideas are applicable to the real world apply his ideas to his daily life? If so, take him seriously. Otherwise, ignore him. (If the fellow is doing pure mathematics or theology, or teaching poetry, then there is no problem. But if he is doing something applicable, then: red flag.)

Niall immediately detected her weak point and went straight for the jugular: her slogan was that she contributed to employment by having six hundred thousand persons on her staff. He immediately exposed her propaganda with the counterargument—actually developed by Marx and Engels—that large bureaucratic corporations seized control of the state just by being “big employers,” and can then extract benefits at the expense of small businesses. So a company that employs six hundred thousand persons is allowed to wreck the health of citizens with impunity, and to benefit from the implied protection of bailouts (just like American car companies), whereas artisans like hairdressers and cobblers do not get such immunity.

Marketing beyond conveying information is insecurity.

Greed is antifragile—though not its victims.

For Fat Tony, humanity started at the level of “self-ownership.” Now self-ownership for our horizontal friend was vastly more democratic than for his thinking predecessors. It simply meant being the owner of your opinion. And it has nothing to do with wealth, birth, intelligence, looks, shoe size, rather with personal courage.

The incentive of a regulator is to have complex regulation. Again, the insiders are the enemies of the less-is-more rule.

Complex environments with nonlinearities are easier to game than linear ones with a small number of variables. The same applies to the gap between the legal and the ethical.

Departments need to teach something so students get jobs, even if they are teaching snake oil—this got us trapped in a circular system in which everyone knows that the material is wrong but nobody is free enough or has enough courage to do anything about it.

I am convinced that a single person with courage can bring down a collective composed of wimps.

Everything in religious law comes down to the refinements, applications, and interpretations of the Golden Rule, “Don’t do unto others what you don’t want them to do to you.”

A central argument is never a summary—it is more like a generator.

Everything gains or loses from volatility. Fragility is what loses from volatility and uncertainty. The glass on the table is short volatility.

The best way to verify that you are alive is by checking if you like variations.

Remember that food would not have a taste if it weren’t for hunger; results are meaningless without effort, joy without sadness, convictions without uncertainty, and an ethical life isn’t so when stripped of personal risks.