Unsolved problems

Oct 20 JDN 2458777

The beauty and clearness of the dynamical theory, which asserts heat and light to be modes of motion, is at present obscured by two clouds. The first came into existence with the undulatory theory of light, and was dealt with by Fresnel and Dr. Thomas Young; it involved the question, how could the earth move through an elastic solid, such as essentially is the luminiferous ether? The second is the Maxwell-Boltzmann doctrine regarding the partition of energy.


~ Lord Kelvin, April 27, 1900

The above quote is part of a speech where Kelvin basically says that physics is a completed field, with just these two little problems to clear up, “two clouds” in a vast clear horizon. Those “two clouds” Kelvin talked about, regarding the ‘luminiferous ether’ and the ‘partition of energy’? They are, respectively, relativity and quantum mechanics. Almost 120 years later we still haven’t managed to really solve them, at least not in a way that works consistently as part of one broader theory.

But I’ll give Kelvin this: He knew where the problems were. He vastly underestimated how complex and difficult those problems would be, but he knew where they were.

I’m not sure I can say the same about economists. We don’t seem to have even reached the point where we agree where the problems are. Consider another quotation:

For a long while after the explosion of macroeconomics in the 1970s, the field looked like a battlefield. Over time however, largely because facts do not go away, a largely shared vision both of fluctuations and of methodology has emerged. Not everything is fine. Like all revolutions, this one has come with the destruction of some knowledge, and suffers from extremism and herding. None of this deadly however. The state of macro is good.


~ Oliver Blanchard, 2008

The timing of Blanchard’s remark is particularly ominous: It is much like the turkey who declares, the day before Thanksgiving, that his life is better than ever.

But the content is also important: Blanchard didn’t say that microeconomics is in good shape (which I think one could make a better case for). He didn’t even say that economics, in general, is in good shape. He specifically said, right before the greatest economic collapse since the Great Depression, that macroeconomics was in good shape. He didn’t merely underestimate the difficulty of the problem; he didn’t even see where the problem was.

If you search the Web, you can find a few lists of unsolved problems in economics. Wikipedia has such a list that I find particularly bad; Mike Moffatt offers a better list that still has significant blind spots.

Wikipedia’s list is full of esoteric problems that require deeply faulty assumptions to even exist, like the ‘American option problem’ which assumes that the Black-Scholes model is even remotely an accurate description of how option prices work, or the ‘tatonnement problem’ which ignores the fact that there may be many equilibria and we might never reach one at all, or the problem they list under ‘revealed preferences’ which doesn’t address any of the fundamental reasons why the entire concept of revealed preferences may fail once we apply a realistic account of cognitive science. (I could go pretty far afield with that last one—and perhaps I will in a later post—but for now, suffice it to say that human beings often freely choose to do things that we later go on to regret.) I think the only one that Wikipedia’s list really gets right is Unified models of human biases’. The ‘home bias in trade’ and ‘Feldstein-Horioka Puzzle’ problems are sort of edging toward genuine problems, but they’re bound up in too many false assumptions to really get at the right question, which is actually something like “How do we deal with nationalism?” Referring to the ‘Feldstein-Horioka Puzzle’ misses the forest for the trees. Likewise, the ‘PPP Puzzle’ and the ‘Exchange rate disconnect puzzle’ (and to some extent the ‘equity premium puzzle’ as well) are really side effects of a much deeper problem, which is that financial markets in general are ludicrously volatile and inefficient and we have no idea why.

And Wikipedia’s list doesn’t have some of the largest, most important problems in economics. Moffatt’s list does better, including good choices like “What Caused the Industrial Revolution?”, “What Is the Proper Size and Scope of Government?”, and “What Truly Caused the Great Depression?”, but it also includes some of the more esoteric problems like the ‘equity premium puzzle’ and the ‘endogeneity of money’. The way he states the problem “What Causes the Variation of Income Among Ethnic Groups?” suggests that he doesn’t quite understand what’s going on there either. More importantly, Moffatt still leaves out very obviously important questions like “How do we achieve economic development in poor countries?” (Or as I sometimes put it, “What did South Korea do from 1950 to 2000, and how can we do it again?”), “How do we fix shortages of housing and other necessities?”, “What is causing the global rise of income and wealth inequality?”, “How altruistic are human beings, to whom, and under what conditions?” and “What makes financial markets so unstable?” Ironically, ‘Unified models of human biases’, the one problem that Wikipedia got right, is missing from Moffatt’s list.

And I’m also humble enough to realize that some of the deepest problems in economics may be ones that we don’t even quite know how to formulate yet. We like to pretend that economics is a mature science, almost on the coattails of physics; but it’s really a very young science, more like psychology. We go through these ‘cargo cult science‘ rituals of p-values and econometric hypothesis tests, but there are deep, basic forces we don’t understand. We have precisely prepared all the apparatus for the detection of the phlogiston, and by God, we’ll get that 0.05 however we have to. (Think I’m being too harsh? “Real Business Cycle” theory essentially posits that the Great Depression was caused by everyone deciding that they weren’t going to work for a few years, and as whole countries fell into the abyss from failing financial markets, most economists still clung to the Efficient Market Hypothesis.) Our whole discipline requires major injections of intellectual humility: We not only don’t have all the answers; we’re not even sure we have all the questions.

I think the esoteric nature of questions like ‘the equity premium puzzle’ and the ‘tatonnement problem‘ is precisely the source of their appeal: It’s the sort of thing you can say you’re working on and sound very smart, because the person you’re talking to likely has no idea what you’re talking about. (Or else they are a fellow economist, and thus in on the con.) If you said that you’re trying to explain why poor countries are poor and why rich countries are rich—and if economics isn’t doing that, then what in the world are we doing?you’d have to admit that we honestly have only the faintest idea, and that millions of people have suffered from bad advice economists gave their governments based on ideas that turned out to be wrong.

It’s really quite problematic how closely economists are tied to policymaking (except when we do really know what we’re talking about?). We’re trying to do engineering without even knowing physics. Maybe there’s no way around it: We have to make some sort of economic policy, and it makes more sense to do it based on half-proven ideas than on completely unfounded ideas. (Engineering without physics worked pretty well for the Romans, after all.) But it seems to me that we could be relying more, at least for the time being, on the experiences and intuitions of the people who have worked on the ground, rather than on sophisticated theoretical models that often turn out to be utterly false. We could eschew ‘shock therapy‘ approaches that try to make large interventions in an economy all at once, in favor of smaller, subtler adjustments whose consequences are more predictable. We could endeavor to focus on the cases where we do have relatively clear knowledge (like rent control) and avoid those where the uncertainty is greatest (like economic development).

At the very least, we could admit what we don’t know, and admit that there is probably a great deal we don’t know that we don’t know.

Mental illness is different from physical illness.

Post 311 Oct 13 JDN 2458770

There’s something I have heard a lot of people say about mental illness that is obviously well-intentioned, but ultimately misguided: “Mental illness is just like physical illness.”

Sometimes they say it explicitly in those terms. Other times they make analogies, like “If you wouldn’t shame someone with diabetes for using insulin, why shame someone with depression for using SSRIs?”

Yet I don’t think this line of argument will ever meaningfully reduce the stigma surrounding mental illness, because, well, it’s obviously not true.

There are some characteristics of mental illness that are analogous to physical illness—but there are some that really are quite different. And these are not just superficial differences, the way that pancreatic disease is different from liver disease. No one would say that liver cancer is exactly the same as pancreatic cancer; but they’re both obviously of the same basic category. There are differences between physical and mental illness which are both obvious, and fundamental.

Here’s the biggest one: Talk therapy works on mental illness.

You can’t talk yourself out of diabetes. You can’t talk yourself out of myocardial infarct. You can’t even talk yourself out of migraine (though I’ll get back to that one in a little bit). But you can, in a very important sense, talk yourself out of depression.

In fact, talk therapy is one of the most effective treatments for most mental disorders. Cognitive behavioral therapy for depression is on its own as effective as most antidepressants (with far fewer harmful side effects), and the two combined are clearly more effective than either alone. Talk therapy is as effective as medication on bipolar disorder, and considerably better on social anxiety disorder.

To be clear: Talk therapy is not just people telling you to cheer up, or saying it’s “all in your head”, or suggesting that you get more exercise or eat some chocolate. Nor does it consist of you ruminating by yourself and trying to talk yourself out of your disorder. Cognitive behavioral therapy is a very complex, sophisticated series of techniques that require years of expert training to master. Yet, at its core, cognitive therapy really is just a very sophisticated form of talking.

The fact that mental disorders can be so strongly affected by talk therapy shows that there really is an important sense in which mental disorders are “all in your head”, and not just the trivial way that an axe wound or even a migraine is all in your head. It isn’t just the fact that it is physically located in your brain that makes a mental disorder different; it’s something deeper than that.

Here’s the best analogy I can come up with: Physical illness is hardware. Mental illness is software.

If a computer breaks after being dropped on the floor, that’s like an axe wound: An obvious, traumatic source of physical damage that is an unambiguous cause of the failure.

If a computer’s CPU starts overheating, that’s like a physical illness, like diabetes: There may be no particular traumatic cause, or even any clear cause at all, but there is obviously something physically wrong that needs physical intervention to correct.

But if a computer is suffering glitches and showing error messages when it tries to run particular programs, that is like mental illness: Something is wrong not on the low-level hardware, but on the high-level software.

These different types of problem require different types of solutions. If your CPU is overheating, you might want to see about replacing your cooling fan or your heat sink. But if your software is glitching while your CPU is otherwise running fine, there’s no point in replacing your fan or heat sink. You need to get a programmer in there to look at the code and find out where it’s going wrong. A talk therapist is like a programmer: The words they say to you are like code scripts they’re trying to get your processor to run correctly.

Of course, our understanding of computers is vastly better than our understanding of human brains, and as a result, programmers tend to get a lot better results than psychotherapists. (Interestingly they do actually get paid about the same, though! Programmers make about 10% more on average than psychotherapists, and both are solidly within the realm of average upper-middle-class service jobs.) But the basic process is the same: Using your expert knowledge of the system, find the right set of inputs that will fix the underlying code and solve the problem. At no point do you physically intervene on the system; you could do it remotely without ever touching it—and indeed, remote talk therapy is a thing.

What about other neurological illnesses, like migraine or fibromyalgia? Well, I think these are somewhere in between. They’re definitely more physical in some sense than a mental disorder like depression. There isn’t any cognitive content to a migraine the way there is to a depressive episode. When I feel depressed or anxious, I feel depressed or anxious about something. But there’s nothing a migraine is about. To use the technical term in cognitive science, neurological disorders lack the intentionality that mental disorders generally have. “What are you depressed about?” is a question you usually can answer. “What are you migrained about?” generally isn’t.

But like mental disorders, neurological disorders are directly linked to the functioning of the brain, and often seem to operate at a higher level of functional abstraction. The brain doesn’t have pain receptors on itself the way most of your body does; getting a migraine behind your left eye doesn’t actually mean that that specific lobe of your brain is what’s malfunctioning. It’s more like a general alert your brain is sending out that something is wrong, somewhere. And fibromyalgia often feels like it’s taking place in your entire body at once. Moreover, most neurological disorders are strongly correlated with mental disorders—indeed, the comorbidity of depression with migraine and fibromyalgia in particular is extremely high.

Which disorder causes the other? That’s a surprisingly difficult question. Intuitively we might expect the “more physical” disorder to be the primary cause, but that’s not always clear. Successful treatment for depression often improves symptoms of migraine and fibromyalgia as well (though the converse is also true). They seem to be mutually reinforcing one another, and it’s not at all clear which came first. I suppose if I had to venture a guess, I’d say the pain disorders probably have causal precedence over the mood disorders, but I don’t actually know that for a fact.

To stretch my analogy a little, it may be like a software problem that ends up causing a hardware problem, or a hardware problem that ends up causing a software problem. There actually have been a few examples of this, like games with graphics so demanding that they caused GPUs to overheat.

The human brain is a lot more complicated than a computer, and the distinction between software and hardware is fuzzier; we don’t actually have “code” that runs on a “processor”. We have synapses that continually fire on and off and rewire each other. The closest thing we have to code that gets processed in sequence would be our genome, and that is several orders of magnitude less complex than the structure of our brains. Aside from simply physically copying the entire brain down to every synapse, it’s not clear that you could ever “download” a mind, science fiction notwithstanding.

Indeed, anything that changes your mind necessarily also changes your brain; the effects of talking are generally subtler than the effects of a drug (and certainly subtler than the effects of an axe wound!), but they are nevertheless real, physical changes. (This is why it is so idiotic whenever the popular science press comes out with: “New study finds that X actually changes your brain!” where X might be anything from drinking coffee to reading romance novels. Of course it does! If it has an effect on your mind, it did so by having an effect on your brain. That’s the Basic Fact of Cognitive Science.) This is not so different from computers, however: Any change in software is also a physical change, in the form of some sequence of electrical charges that were moved from one place to another. Actual physical electrons are a few microns away from where they otherwise would have been because of what was typed into that code.

Of course I want to reduce the stigma surrounding mental illness. (For both selfish and altruistic reasons, really.) But blatantly false assertions don’t seem terribly productive toward that goal. Mental illness is different from physical illness; we can’t treat it the same.

Trump is finally being impeached

Post 310 Oct 6 JDN 2458763

Given that there have been efforts to impeach Trump since before he took office (which is totally unprecedented, by the way; while several others have committed crimes and been impeached while in office, no other US President has gone into office with widespread suspicion of mass criminal activity), it seems odd that it has taken this long to finally actually start formal impeachment hearings.

Why did it take so long? We needed two things to happen: One, absolutely overwhelming evidence of absolutely flagrant crimes, and two, a Democratic majority in the House of Representatives.

This is how divided America has become. If the Republicans were really a mainstream center-right party as they purport to be, they would have supported impeachment just as much as the Democrats, we would have impeached Trump in 2017, and he would have been removed from office by 2018. But in fact they are nothing of the sort. The Republicans no longer believe in democracy. The Democrats are a mainstream center-right party, and the Republicans are far-right White-nationalist crypto-fascists (and less ‘crypto-‘ all the time). After seeing how they reacted to his tax evasion, foreign bribes, national security leaks, human rights violations, obstruction of justice, and overall ubiquitous corruption and incompetence, by this point it’s clear that there is almost nothing that Trump could do which would make either the voter base or the politicians of the Republican Party turn against him—he may literally be correct that he could commit a murder in broad daylight on Fifth Avenue. Maybe if he raised taxes on billionaires or expressed support for Roe v. Wade they would finally revolt.

Even as it stands, there is good reason to fear that the Republican-majority Senate will not confirm the impeachment and remove Trump from office. The political fallout from such a failed impeachment is highly uncertain. So far, markets are taking it in stride; it may even turn out to be good for the economy. (Then again, a good economy may be good for Trump in 2020!) But at this point the evidence is so damning that if we don’t impeach now, we may never impeach again; if this isn’t enough, nothing is. (The Washington Examiner said that months ago, and may already have been right; but the case is even stronger now.)

So, the most likely scenario is that the impeachment goes through the House, but fails in the Senate. The good news is that if the Republicans do block the impeachment, they’ll be publicly admitting that even charges this serious and this substantiated mean nothing to them. Anyone watching who is still on the fence about them will see how corrupt they have become.

After that, this is probably what will happen: The impeachment will be big news for a month or two, then be largely ignored. Trump will probably try to make himself a martyr, talking even louder about ‘witch hunts’. He will lose popularity with a few voters, but his base will continue to support him through thick and thin. (Astonishingly, almost nothing really seems to move his overall approval rating.) The economy will be largely unaffected, or maybe slightly improve. And then we’ll find out in the 2020 election whether the Democrats can mobilize enough opposition to Trump, and—just as importantly—enough support for whoever wins the primaries, to actually win this time around.

If by some miracle enough Republicans find a moral conscience and vote to remove Trump from office, this means that until 2020 we will have President Mike Pence. In a sane world, that in itself would sound like a worst-case scenario; he’s basically a less-sleazy Ted Cruz. He is misogynistic, homophobic, and fanatically religious. He is also a partisan ideologue who toes the party line on basically every issue. Some have even argued that Pence is worse than Trump, because he represents the same ideology but with more subtlety and competence.

But subtlety and competence are important. Indeed, I would much rather have an intelligent, rational, competent ideologue managing our government, leading our military, and controlling our nuclear launch codes than an idiotic, narcissistic, impulsive one. Pence at least can be trusted to be consistent in his actions and diplomatic in his words—two things which Trump has absolutely never been.

Indeed, Pence’s ideological consistency has benefits; unlike Trump, he reliably supports free trade and his fiscal conservatism actually seems genuine for once. Consistency in itself has value: Life is much easier, and the economy is much stronger, when the rules of the game remain the same rather than randomly lurching from one extreme to another.

Pence is also not the pathological liar that Trump is. Yes, Pence has lied many times (only 22% of his statements were evaluated by PolitiFact as “Mostly True” or “True”, and 30% were “False” or “Pants on Fire”). But Trump lies constantly. A mere 14% of Trump’s statements were evaluated by Trump as “Mostly True” or “True”, while 48% were “False” or “Pants on Fire”. For Bernie Sanders, 49% were “Mostly True” or better, and only 11% were “False”, with no “Pants on Fire” at all; for Hillary Clinton, 49% were “Mostly True” or better, and only 10% were “False”, with 3% “Pants on Fire”. People have tried to keep running tallies of Trump’s lies, but it’s a tall order: The Washington Post records over 12,000 lies since he took office less than three years ago. Four thousand lies a year. More than ten every single day. Most people commit lies of omission or say ‘white lies’ several times per day (depending on who you ask, I’ve seen everything from an average of 2 times per day to an average of 100 times per day), but that’s not what we’re talking about here. These are consequential, outright statements of fact that aren’t true. And these are not literally everything he has said that wasn’t true; they are only public lies with relevance to policy or his own personal record. Indeed, Trump lies recklessly, stupidly, pointlessly, nonsensically. He seems like a pathological liar, or someone with dementia who is confabulating to try to fill gaps in his memory. (Indeed, a lot of his behavior is consistent with dementia, and similar to how Reagan acted in the early days of his Alzheimer’s.) At least if Pence takes office, we’ll be able to believe some of what he says.

Of course, Pence won’t be much better on some of the most important issues, such as climate change. When asked how important he thinks climate change is and what should be done about it, Pence always gives mealy-mouthed, evasive responses—but at least he doesn’t make up stories about windmills getting special permits to kill endangered birds.

I admit, choosing Pence over Trump feels like choosing to get shot in the leg instead of the face—but that’s really not a difficult choice, is it?

Migration holds together the American Dream

Sep 29 JDN 2458757

The United States is an exceptional country in many ways, some good (highest income), some bad (highest incarceration rate), and some mixed (largest military). But as you compare the US to other countries, one thing that will immediately strike you is how we are a nation of migrants.

I don’t just mean immigrants, people who moved to the country after being born here—though we certainly are also a country of immigrants. About 99% of the US population descends from immigrants, mostly European—there aren’t a lot of countries that can even say the majority of their population migrated from another continent. Over 45 million Americans are foreign-born, which is not only the highest in the world; it is almost one-fifth of all the immigrants in the world. We experience a net inflow of immigrants averaging over 1 million people per year, by far the highest in the world. Almost half of the increase in our workforce over the last decade was due to immigrants.

But the US is full of migration in another way, which may in fact be even more important: Internal migration, from country to city, from one city to another, or from one state to another. Every year, about 12.5% of Americans move somewhere; about 10% move to a different state. No other country even comes close to this level of internal migration. According to the US census, about two-thirds of moves are within the same county, and yet each year there are ten times as many Americans who moved to a different county as there are immigrants to the United States. There are more cross-state migrants to California and Texas alone than there are immigrants to the entire country. There are about as many people who move each year within the United States as there are foreign-born individuals total.

This internal migration is central to the high productivity of the American economy. Internal migration is central to the process of urbanization, which drives a great deal of economic development. It is not a coincidence that the United States is one of the world’s most urbanized countries as well as one of the richest, nor that the ranking of US states by urbanization and the ranking of US states by per-capita income look very much alike.

Income_Urbanization

On average, increasing a state’s urbanization by 1 percentage point increases its average per-capita income by $270 per year (in chained 2009 dollars); since most of that increase is going to the people who actually moved, this means that the average income increase as a result of moving from the country to the city is likely over $20,000 per year. To put it another way, if Maine could become as urbanized as California, we would expect its per-capita income to increase from about $39,000 per year to about $54,000 per year—which is just about California’s per-capita income.

Indeed, migration is probably the one thing holding up our otherwise dismal level of income mobility, which still trails behind most other First World countries (and far behind Denmark and Norway, because #ScandinaviaIsBetter). Canada also does extremely well in terms of income mobility, and Canada also has a high rate of internal migration, with almost 1% of Canadians moving to a new province in any given year. Canada is probably what the US would look like with a European-style social safety net; our high internal migration rate might actually get us better income mobility than is currently achieved by say France or Germany.

Indeed, migration may be the main reason there is still some vestige of an American Dream. It’s not what it used to be, but it isn’t yet dead either. Two-thirds of American adults have more real (inflation-adjusted) income than their parents. Intergenerational income mobility in the US grew quickly in the 1940s and 1950s, grew more slowly in the 1960s and 1970s, and has been stagnant ever since. While the odds of moving to a different income bracket have remained stable, income inequality has increased over the last 40 years, which means that the differences between those brackets have become larger.

Why will no one listen to economists on rent control?

Sep 22 JDN 2458750

I am on the verge of planting my face into my desk, because California just implemented a statewide program of rent control. I understand the good intentions here; it is absolutely the case that housing in California is too expensive. There are castles in Spain cheaper than condos in California. But this is not the right solution. Indeed, it will almost certainly make the problem worse. Maybe housing prices won’t be too high; instead there simply won’t be enough homes and more people will live on the street. (It’s not a coincidence that the Bay Area has both some of the world’s tightest housing regulations and one of the highest rates of homelessness.)

There is some evidence that rent control can help keep tenants in their homes—but at the cost of reducing the overall housing supply. Most of the benefits of rent control actually fall upon the upper-middle-class, not the poor.

Price controls are in general a terrible way of intervening in the economy. Price controls are basically what destroyed Venezuela. In this case the ECON 101 argument is right: Put a cap on the price of something, and you will create a shortage of that thing. Always.

California makes this worse by including all sorts of additional regulations on housing construction. Some regulations are necessary—homes need to be safe to live in—but did we really need a “right to sunlight”? How important is “the feel of the city” compared to homelessness? Not every building needs its own parking! (That, at least, the state government seems to be beginning to understand.) And yes, we should be investing heavily in solar power, and rooftops are a decent place to put those solar panels; but you should be subsidizing solar panels, not mandating them and thereby adding the cost of solar panels to the price of every new building.

Of course, we can’t simply do nothing; we need to fix this housing crisis. But there are much better ways of doing so. Again the answer is to subsidize rather than regulate.

Here are some policy options for making housing more affordable:

  1. Give every person below a certain income threshold a one-time cash payment to help them pay for a down payment or first month’s rent. Gradually phase out the payment as their income increases in the same way as the Earned Income Tax Credit.
  2. Provide a subsidy for new housing construction, with larger subsidies for buildings with smaller, more affordable apartments.
  3. Directly pay for the construction of new public housing.
  4. Relax zoning regulations to make construction less expensive.
  5. Redistribute income from the rich to the poor using progressive taxes and transfer payments. Housing crises are always and everywhere a problem of inequality.

Some of these would cost money, yes; we would probably need to raise taxes to pay for them. But rent control has costs too. We are already paying these costs, but instead of paying them in the form of taxes that can be concentrated on the rich, we pay them in the form of a housing crisis that hurts the poor most of all.

The weirdest thing about all this is that any economist would agree.

Economists can be a contentious bunch: It has been said that if you ask five economists a question, you’ll get five answers—six if one is from Harvard. Yet the consensus among economists against rent control is absolutely overwhelming. Analyses of journal articles and polls of eminent economists suggest that over 90% of economists, regardless of their other views or their political leanings, agree that rent control is a bad idea.

This is a staggering result: There are economists who think that almost all taxes and regulations are fundamentally evil and should all be removed, and economists who think that we need radical, immediate government intervention to prevent a global climate catastrophe. But they all agree that rent control is a bad idea.

Economists differ in their views about legacy college admissions, corporate antitrust, wealth taxes, corporate social responsibility, equal pay for women, income taxes, ranked-choice voting, the distributional effects of monetary policy, the relation between health and economic growth, minimum wage, and healthcare spending. They disagree about whether Christmas is a good thing! But they all agree that rent control is a bad idea.

We’re not likely to ever get a consensus much better than this in any social science. The economic case against rent control is absolutely overwhelming. Why aren’t policymakers listening to us?

I really would like to know. It’s not that economists have ignored the problem of housing affordability. We have suggested a variety of other solutions that would obviously be better than rent control—in fact, I just did, earlier in this post. Many of them would require tax money, yes—do you want to fix this problem, or not?

Maybe that’s it: Maybe policymakers don’t really care about making housing affordable. If they did, they’d be willing to bear the cost of raising taxes on millionaires in order to build more apartments and keep people from being homeless. But they want to seem like they care about making housing affordable, because they know their constituents care. So they use a policy that seems to make housing more affordable, even though it doesn’t actually work, because that policy also doesn’t affect the government budget (at least not obviously or directly—of course it still does indirectly). They want the political support of the poor, who think this will help them; and they also want the political support of the rich, who refuse to pay a cent more in taxes.

But it really makes me wonder what we as economists are even really doing: If the evidence is this clear and the consensus is this overwhelming, and policymakers still ignore us—then why even bother?

Billionaires bear the burden of proof

Sep 15 JDN 2458743

A king sits atop a golden throne, surrounded by a thousand stacks of gold coins six feet high. A hundred starving peasants beseech him for just one gold coin each, so that they might buy enough food to eat and clothes for the winter. The king responds: “How dare you take my hard-earned money!”

This is essentially the world we live in today. I really cannot emphasize enough how astonishingly, horrifically, mind-bogglingly rich billionares are. I am writing this sentence at 13:00 PDT on September 8, 2019. A thousand seconds ago was 12:43, about when I started this post. A million seconds ago was Wednesday, August 28. A billion seconds ago was 1987. I will be a billion seconds old this October.

Jeff Bezos has $170 billion. 170 billion seconds ago was a thousand years before the construction of the Great Pyramid. To get as much money as he has gaining one dollar per second (that’s $3600 an hour!), Jeff Bezos would have had to work for as long as human civilization has existed.

At a more sensible wage like $30 per hour (still better than most people get), how long would it take to amass $170 billion? Oh, just about 600,000 years—or about twice the length of time that Homo sapiens has existed on Earth.

How does this compare to my fictional king with a thousand stacks of gold? A typical gold coin is worth about $500, depending on its age and condition. Coins are about 2 millimeters thick. So a thousand stacks, each 2 meters high, would be about $500*1000*1000 = $500 million. This king isn’t even a billionaire! Jeff Bezos has three hundred times as much as him.

Coins are about 30 millimeters in diameter, so assuming they are packed in neat rows, these thousand stacks of gold coins would fill a square about 0.9 meters to a side—in our silly Imperial units, that’s 3 feet wide, 3 feet deep, 6 feet tall. If Jeff Bezo’s stock portfolio were liquidated into gold coins (which would require about 2% of the world’s entire gold supply and surely tank the market), the neat rows of coins stacked a thousand high would fill a square over 16 meters to a side—that’s a 50-foot-wide block of gold coins. Smaug’s hoard in The Hobbit was probably about the same amount of money as what Jeff Bezos has.

And yet, somehow there are still people who believe that he deserves this money, that he earned it, that to take even a fraction of it away would be a crime tantamount to theft or even slavery.

Their arguments can be quite seductive: How would you feel about the government taking your hard-earned money? Entrepreneurs are brilliant, dedicated, hard-working people; why shouldn’t they be rewarded? What crime do CEOs commit by selling products at low prices?

The way to cut through these arguments is to never lose sight of the numbers. In defense of a man who had $5 million or even $20 million, such an argument might make sense. I can imagine how someone could contribute enough to humanity to legitimately deserve $20 million. I can understand how a talented person might work hard enough to earn $5 million. But it’s simply not possible for any human being to be so brilliant, so dedicated, so hard-working, or make such a contribution to the world, that they deserve to have more dollars than there have been seconds since the Great Pyramid.

It’s not necessary to find specific unethical behaviors that brought a billionaire to where he (and yes, it’s nearly always he) is. They are generally there to be found: At best, one becomes a billionaire by sheer luck. Typically, one becomes a billionaire by exerting monopoly power. At worst, one can become a billionaire by ruthless exploitation or even mass murder. But it’s not our responsibility to point out a specific crime for every specific billionaire.

The burden of proof is on billionaires: Explain how you can possibly deserve that much money.

It’s not enough to point to some good things you did, or emphasize what a bold innovator you are: You need to explain what you did that was so good that it deserves to be rewarded with Smaug-level hoards of wealth. Did you save the world from a catastrophic plague? Did you end world hunger? Did you personally prevent a global nuclear war? I could almost see the case for Norman Borlaug or Jonas Salk earning a billion dollars (neither did, by the way). But Jeff Bezos? You didn’t save the world. You made a company that sells things cheaply and ships them quickly. Get over yourself.

Where exactly do we draw that line? That’s a fair question. $20 million? $100 million? $500 million? Maybe there shouldn’t even be a hard cap. There are many other approaches we could take to reducing this staggering inequality. Previously I have proposed a tax system that gets continuously more progressive forever, as well as a CEO compensation cap based on the pay of the lowliest employees. We could impose a wealth tax, as Elizabeth Warren has proposed. Or we could simply raise the top marginal rate on income tax to something more like what it was in the 1960s. Or as Republicans today would call it, radical socialism.

The backfire effect has been greatly exaggerated

Sep 8 JDN 2458736

Do a search for “backfire effect” and you’re likely to get a large number of results, many of them from quite credible sources. The Oatmeal did an excellent comic on it. The basic notion is simple: “[…]some individuals when confronted with evidence that conflicts with their beliefs come to hold their original position even more strongly.”

The implications of this effect are terrifying: There’s no point in arguing with anyone about anything controversial, because once someone strongly holds a belief there is nothing you can do to ever change it. Beliefs are fixed and unchanging, stalwart cliffs against the petty tides of evidence and logic.

Fortunately, the backfire effect is not actually real—or if it is, it’s quite rare. Over many years those seemingly-ineffectual tides can erode those cliffs down and turn them into sandy beaches.

The most recent studies with larger samples and better statistical analysis suggest that the typical response to receiving evidence contradicting our beliefs is—lo and behold—to change our beliefs toward that evidence.

To be clear, very few people completely revise their worldview in response to a single argument. Instead, they try to make a few small changes and fit them in as best they can.

But would we really expect otherwise? Worldviews are holistic, interconnected systems. You’ve built up your worldview over many years of education, experience, and acculturation. Even when someone presents you with extremely compelling evidence that your view is wrong, you have to weigh that against everything else you have experienced prior to that point. It’s entirely reasonable—rational, even—for you to try to fit the new evidence in with a minimal overall change to your worldview. If it’s possible to make sense of the available evidence with only a small change in your beliefs, it makes perfect sense for you to do that.

What if your whole worldview is wrong? You might have based your view of the world on a religion that turns out not to be true. You might have been raised into a culture with a fundamentally incorrect concept of morality. What if you really do need a radical revision—what then?

Well, that can happen too. People change religions. They abandon their old cultures and adopt new ones. This is not a frequent occurrence, to be sure—but it does happen. It happens, I would posit, when someone has been bombarded with contrary evidence not once, not a few times, but hundreds or thousands of times, until they can no longer sustain the crumbling fortress of their beliefs against the overwhelming onslaught of argument.

I think the reason that the backfire effect feels true to us is that our life experience is largely that “argument doesn’t work”; we think back to all the times that we have tried to convince to change a belief that was important to them, and we can find so few examples of when it actually worked. But this is setting the bar much too high. You shouldn’t expect to change an entire worldview in a single conversation. Even if your worldview is correct and theirs is not, that one conversation can’t have provided sufficient evidence for them to rationally conclude that. One person could always be mistaken. One piece of evidence could always be misleading. Even a direct experience could be a delusion or a foggy memory.

You shouldn’t be trying to turn a Young-Earth Creationist into an evolutionary biologist, or a climate change denier into a Greenpeace member. You should be trying to make that Creationist question whether the Ussher chronology is really so reliable, or if perhaps the Earth might be a bit older than a 17th century theologian interpreted it to be. You should be getting the climate change denier to question whether scientists really have such a greater vested interest in this than oil company lobbyists. You can’t expect to make them tear down the entire wall—just get them to take out one brick today, and then another brick tomorrow, and perhaps another the day after that.

The proverb is of uncertain provenance, variously attributed, rarely verified, but it is still my favorite: No single raindrop feels responsible for the flood.

Do not seek to be a flood. Seek only to be a raindrop—for if we all do, the flood will happen sure enough. (There’s a version more specific to our times: So maybe we’re snowflakes. I believe there is a word for a lot of snowflakes together: Avalanche.)

And remember this also: When you argue in public (which includes social media), you aren’t just arguing for the person you’re directly engaged with; you are also arguing for everyone who is there to listen. Even if you can’t get the person you’re arguing with to concede even a single point, maybe there is someone else reading your post who now thinks a little differently because of something you said. In fact, maybe there are many people who think a little differently—the marginal impact of slacktivism can actually be staggeringly large if the audience is big enough.

This can be frustrating, thankless work, for few people will ever thank you for changing their mind, and many will condemn you even for trying. Finding out you were wrong about a deeply-held belief can be painful and humiliating, and most people will attribute that pain and humiliation to the person who called them out for being wrong—rather than placing the blame where it belongs, which is on whatever source or method made you wrong in the first place. Being wrong feels just like being right.

But this is important work, among the most important work that anyone can do. Philosophy, mathematics, science, technology—all of these things depend upon it. Changing people’s minds by evidence and rational argument is literally the foundation of civilization itself. Every real, enduring increment of progress humanity has ever made depends upon this basic process. Perhaps occasionally we have gotten lucky and made the right choice for the wrong reasons; but without the guiding light of reason, there is nothing to stop us from switching back and making the wrong choice again soon enough.

So I guess what I’m saying is: Don’t give up. Keep arguing. Keep presenting evidence. Don’t be afraid that your arguments will backfire—because in fact they probably won’t.