The often angry-looking Nassim Taleb just published a book of unlinked tweets: The Bed of Procrustes. It is short and has a Kindle version that costs 72 cents less than the hardcopy.
As to its flaws, it reminded me of one of my favorite aphorisms: "the man who early on regards himself as genius is lost.” He inverts the observation that geniuses are often misunderstood to the insight that misunderstood people are geniuses, and critics of such people are imbeciles who don’t even have the taste to appreciate genius. My criticisms are therefore consistent with him being right or wrong, but falsification is not symptomatic of punditry in general or Taleb in particular.
It is a golden rule not to judge men by the opinions but rather by what their opinions make of them. His many fans highlight the effect of Taleb's thinking as they speak like Renfield discussing Count Dracula:
”excellent; it's a must read ... I'll refrain from demonstrating my foolishness and ignorance by trying to interpret any of them in this forum.” ★★★★★
“Those who understand the book will refrain from summarizing its message.” ★★★★★
They sound like a cult of scared guru worshipers.
I suspect that Taleb dreams of someday winning the Nobel Prize in Economics for his popularization of Rietz’s peso problem (1988), fat tailed distributions (Mandelbroit 1963), or Knightian uncertainty (1921), at which point he would refuse it and then raise his stature above all those before him. Alas, as defective as the econ Nobel is, it ain't the Peace Prize. He has not added any new significant idea to any of these richly researched threads, rather merely tries to convince readers he and his followers are the only ones in the world who really understand them. For example, he extensively documents that financial time series are not exactly Gaussian, something financial standard bearer Eugene Fama investigated in his 1960's dissertation. He meticulously proved something everybody in the field has known for decades.
Winston Churchill said ‘It is a good thing for an uneducated man to read books of quotations’, and I agree. Many useful truths in mathematics and physics are old hat but essential pillars of wisdom, concise, and so too for the many proverbs that have been handed down to us. Readers usually retain aphorisms they parse out of an author’s sustained argument, a pithy summary (eg, Smith’s ‘By pursuing his own interest he frequently promotes that of the society more effectually than when he really intends to promote it’). Taleb knocks out the middle-man and publishes a couple hundred of his random thoughts.
Such a book needs a certain predisposition because when Chauncey Gardiner said 'there will be growth in the spring' in the movie Being There, it was considered profound basically on how you perceived the vehicle spouting such statements. Consider that the most absurd economic proposition will be taken seriously if you can find it in Keynes's General Theory, in which case, it's an argument that deserves consideration (Pay men to dig holes and fill them in again? GT p.220, really). Thus Taleb gives us these beauties:
"Fortune punishes the greedy by making him poor and the very greedy by making him rich."
"Karl Marx, a visionary, figured out that you can control a slave better by convincing him he is an employee."
"Sports femininize men and masculinize women."
"Every ten years collective wisdom degrades by half."
"The nation-state: apartheid without political incorrectness."
Perhaps his acolytes are correct, these remarks defy exegesis. But if you aren't going to make sense, you might as well be funny: Marx's 'time flies like an arrow, fruit flies like a banana.' Taleb's humor is less like Groucho, more like Karl.
Kanye West is also very popular, and like Taleb tweets his fans with petulant rants. Consider these Kanye Classics:
“Because I have sacrificed real life to be a celebrity and to give this art to people, which is great. It is great that I was able to do that…”
“I am God’s vessel. But my greatest pain in life is that I will never be able to see myself perform live.”
“You want me to be great, but you don’t ever want me to say I’m great?”
"George Bush doesn't care about black people."
Modesty is a virtue not because it implies servile humility, but because it implies a combination of honesty and knowledge. Using self-righteous anger to justify immodesty just highlights one's immaturity. Here's Taleb channeling his inner Kanye:
"Your reputation is harmed the most by what you say to defend it."
"A genius is someone with flaws harder to imitate than his qualities."
"It is a waste of emotion to answer critics."
"Bad mouthing is the only genuine expression of admiration."
"People reserve standard compliments to those who do not threaten their pride; the others they often praise by calling 'arrogant'."
"It is the appearance of inconsistency, and not its absence, that makes people attractive."
The last thing most people need to think is that criticism is mainly from fools who misunderstand genius, because as I've entered middle age and had children I have found 1) children are learning and a fast rate while most adults have stopped learning and 2) adults can avoid criticism, whereas a child cannot. These are not unrelated.
It is frustrating when people dismiss your ideas and it's comforting to imagine they are all envious fools not worthy of your genius, yet this is just succumbing to your baser instincts. Like everyone else I don't like criticism, and when I was young I was insecure and immodest, and this hurt me in many ways. Over time wisdom has made me more confident and humble. Thus, while my CPU may be slowing and RAM shrinking, I'm processing feedback more efficiently than I used to, and I wish I appreciated the value of modesty earlier.
Criticism and advice are often wrong, but that merely highlights it is not a sufficient condition to becoming a better person, only a necessary one. Life is too short to learn everything by trial and error, so watching and listening to others is essential. A bias that critics are cretins leads to a life guided only by errors so great they can not be ignored, an inefficient path to enlightenment.
I do agree with a lot of what Taleb says, but as he is pridefully inconsistent (it makes one interesting, supposedly), this does not mean much because once you say 1+1=1, everything, true and untrue, is implied. For example, he states the detection of false patterns is a major problem, excluding the pattern of increased falsely perceived patterns; he's a rebel telling the academy what they don't want to hear, yet his arguments have deep academic threads; data are definitive and the past is misleading. These are not profound paradoxes but rather confused ramblings. It would take a lot of psilocybin for his oeuvre to seem deep to me.
An unqualified glowing NY Times review of "The Bed of Procrustes" references this interview as exemplifying his trenchant criticisms, as he states ‘we should eliminate value-at-risk.’ In The Bed, Taleb argues that 'knowledge' is knowing what does not work as opposed to what does, but this is just letting perfection being the enemy of the good. All theories are wrong, some are useful. If you eliminate Value-at-Risk, what do you replace it with?
As a tool, Value-at-Risk is better than nothing. It is also better than something like the TSA's nonquantifiable terrorist threat indicator. Indeed, one very nice thing about Value-at-Risk, it can be wrong! It can be tested and calibrated at reasonable extremums to capture some of the nonlinear risks in a portfolio, whereas threat level 'orange' remains not even wrong. A metric that captures 1 in 20 events balances the objectives of calibrating a risk metric and capturing some nonlinearity, because you need to generate real observations to calibrate (it isn't applicable to portfolios with assets held for several weeks or more). There’s a trade-off between capturing only the tail events that really matter, and empirically validating the metric.
Value-at-Risk is not perfect, but prior to this you had a jumble of indicators that were not comparable, and logically you usually can't say an array of indicators is 'high' or 'low', just that some items are higher and some are lower, and this leads to an ambiguous interpretation, and impossible testing and calibration. Imagine trying to have a discussion about risk at desk with currency, equity, and bond exposures, all with their various derivatives. If you are not allowed to bucket risks into groups and add them up using some consistent methodology it would be and endless narrative with lots of adverbs.
As to Taleb’s admonition to not ‘confuse the map for the territory’, that was a cliche in the 1960s. More importantly, the problem is not omnipresent but rather selective, because ‘theory free’ observation is not suboptimal, rather impossible. The real issue is which theories are bad and in what ways, not that theory is bad.
For example, like Taleb I find many economic models excessively rigorous because such theories do not add precision or clarity to an idea, only faux sophistication. Thus, Romer's growth theory, or Krugman's increasing returns to scale theory, did not add clarity to an existing debate, only false rigor to ideas more clearly and accurately stated in words. Note that even Romer and Krugman don't build arguments on their models, rather they merely use them for presenting their bona fides. The models are mainly for proving one is clever as opposed to making a novel point. A formalization of well-known arguments that disingenuously presents itself as 'new' theory is bad because this leads to a wasted focus. Further, some models become so convoluted they make falsification impossible, allowing an intellectual error to persist for a generation as true believers can always point to different parameterizations that work (eg, input-output macro models, large-scale Keynesian macro models, stochastic discount factors).
Hayek's theory of the importance of markets and profit seeking in decentralizing incentives, Adam Smith's Invisible Hand, the Coase Theorem, and George Stigler’s theory of search and information, meanwhile, were real advances in our understanding of economics, and these did not entail sophisticated mathematical equations. ‘Example’ is more intellectually honest than ‘theorem’ when presenting an economic argument. Representing an idea using measure theory is considered top academic work, but it’s usually pure pedantry.
Unfortunately, the idea that some rigor is good got turned into an arms race in rigor. Really important economic ideas that necessitate heavy mathematics are rare, confined almost exclusively within game theory (eg, Arrow’s Impossibility Theorem, Harsanyi’s general Bayesian model of games, Hurwicz’s mechanism design, Meyerson’s revelation principle), and game theory itself has been much less fruitful than originally thought. Continuous time, Hilbert space, real analysis, have not added to our understanding of economic problems, they merely remind us that any simple mathematical idea can be made more rigorous.
As per unlikely events being under appreciated, I would say it is the opposite. Most internet spam and investment scams are based on things that could happen but probably won't. Improbable events, when priced, are generally overpriced, largely because they can't be hedged and markets are thin, so as a buyer of these things, you tend to overpay: out-of-the-money options, wacky investment or business ventures. As Tyler Cowen wrote in his otherwise positive review in Slate, this big idea does not work in Taleb's main field of expertise, options (peevish Taleb violated his aphorism to ignore criticism back then, and got very mad at Cowen).
This focus on the improbable can lead to excessive risk taking, such as buying lottery tickets or joining multi-level marketing schemes, and too little risk taking, as when we forgo nuclear power or irradiating eggs because of improbable nightmare scenarios. Pity the investor who bought volatility based on the idea that people under appreciate it, as the straightest volatility play, the ETF VXX, has lost 90% of its value since inception in Jan 2009. The key is not to increase the perceived probabilities of small probability events, rather to get them as correct as possible. Some should go up, some down, and this is hard work.
A really good aphorism is distilled in the context of a broader set of work, such as Bertrand Russell's remark that "One of the symptoms of an approaching nervous breakdown is the belief that one's work is terribly important", which for a man who spent a decade on the futile task of trying to axiomatize mathematics (later proven impossible by Kurt Gödel), is truly profound. It is advice Taleb would do well to take.
fyi: my old review of Taleb's Black Swan
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