Month: July 2017

Social construction is not fact—and it is not fiction

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July 30, JDN 2457965

With the possible exception of politically-charged issues (especially lately in the US), most people are fairly good at distinguishing between true and false, fact and fiction. But there are certain types of ideas that can’t be neatly categorized into fact versus fiction.

First, there are subjective feelings. You can feel angry, or afraid, or sad—and really, truly feel that way—despite having no objective basis for the emotion coming from the external world. Such emotions are usually irrational, but even knowing that doesn’t make them automatically disappear. Distinguishing subjective feelings from objective facts is simple in principle, but often difficult in practice: A great many things simply “feel true” despite being utterly false. (Ask an average American which is more likely to kill them, a terrorist or the car in their garage; I bet quite a few will get the wrong answer. Indeed, if you ask them whether they’re more likely to be shot by someone else or to shoot themselves, almost literally every gun owner is going to get that answer wrong—or they wouldn’t be gun owners.)

The one I really want to focus on today is social constructions. This is a term that has been so thoroughly overused and abused by postmodernist academics (“science is a social construction”, “love is a social construction”, “math is a social construction”, “sex is a social construction”, etc.) that it has almost lost its meaning. Indeed, many people now react with automatic aversion to the term; upon hearing it, they immediately assume—understandably—that whatever is about to follow is nonsense.

But there is actually a very important core meaning to the term “social construction” that we stand to lose if we throw it away entirely. A social construction is something that exists only because we all believe in it.

Every part of that definition is important:

First, a social construction is something that exists: It’s really there, objectively. If you think it doesn’t exist, you’re wrong. It even has objective properties; you can be right or wrong in your beliefs about it, even once you agree that it exists.

Second, a social construction only exists because we all believe in it: If everyone in the world suddenly stopped believing in it, like Tinker Bell it would wink out of existence. The “we all” is important as well; a social construction doesn’t exist simply because one person, or a few people, believe in it—it requires a certain critical mass of society to believe in it. Of course, almost nothing is literally believed by everyone, so it’s more that a social construction exists insofar as people believe in it—and thus can attain a weaker or stronger kind of existence as beliefs change.

The combination of these two features makes social constructions a very weird sort of entity. They aren’t merely subjective beliefs; you can’t be wrong about what you are feeling right now (though you can certainly lie about it), but you can definitely be wrong about the social constructions of your society. But we can’t all be wrong about the social constructions of our society; once enough of our society stops believing in them, they will no longer exist. And when we have conflict over a social construction, its existence can become weaker or stronger—indeed, it can exist to some of us but not to others.

If all this sounds very bizarre and reminds you of postmodernist nonsense that might come from the Wisdom of Chopra randomizer, allow me to provide a concrete and indisputable example of a social construction that is vitally important to economics: Money.

The US dollar is a social construction. It has all sorts of well-defined objective properties, from its purchasing power in the market to its exchange rate with other currencies (also all social constructions). The markets in which it is spent are social constructions. The laws which regulate those markets are social constructions. The government which makes those laws is a social construction.

But it is not social constructions all the way down. The paper upon which the dollar was printed is a physical object with objective factual existence. It is an artifact—it was made by humans, and wouldn’t exist if we didn’t—but now that we’ve made it, it exists and would continue to exist regardless of whether we believe in it or even whether we continue to exist. The cotton from which it was made is also partly artificial, bred over centuries from a lifeform that evolved over millions of years. But the carbon atoms inside that cotton were made in a star, and that star existed and fused its carbon billions of years before any life on Earth existed, much less humans in particular. This is why the statements “math is a social construction” and “science is a social construction” are so ridiculous. Okay, sure, the institutions of science and mathematics are social constructions, but that’s trivial; nobody would dispute that, and it’s not terribly interesting. (What, you mean if everyone stopped going to MIT, there would be no MIT!?) The truths of science and mathematics were true long before we were even here—indeed, the fundamental truths of mathematics could not have failed to be true in any possible universe.

But the US dollar did not exist before human beings created it, and unlike the physical paper, the purchasing power of that dollar (which is, after all, mainly what we care about) is entirely socially constructed. If everyone in the world suddenly stopped accepting US dollars as money, the US dollar would cease to be money. If even a few million people in the US suddenly stopped accepting dollars, its value would become much more precarious, and inflation would be sure to follow.

Nor is this simply because the US dollar is a fiat currency. That makes it more obvious, to be sure; a fiat currency attains its value solely through social construction, as its physical object has negligible value. But even when we were on the gold standard, our currency was representative; the paper itself was still equally worthless. If you wanted gold, you’d have to exchange for it; and that process of exchange is entirely social construction.

And what about gold coins, one of the oldest form of money? There now the physical object might actually be useful for something, but not all that much. It’s shiny, you can make jewelry out of it, it doesn’t corrode, it can be used to replace lost teeth, it has anti-inflammatory properties—and millennia later we found out that its dense nucleus is useful for particle accelerator experiments and it is a very reliable electrical conductor useful for making microchips. But all in all, gold is really not that useful. If gold were priced based on its true usefulness, it would be extraordinarily cheap; cheaper than water, for sure, as it’s much less useful than water. Yet very few cultures have ever used water as currency (though some have used salt). Thus, most of the value of gold is itself socially constructed; you value gold not to use it, but to impress other people with the fact that you own it (or indeed to sell it to them). Stranded alone on a desert island, you’d do anything for fresh water, but gold means nothing to you. And a gold coin actually takes on additional socially-constructed value; gold coins almost always had seignorage, additional value the government received from minting them over and above the market price of the gold itself.

Economics, in fact, is largely about social constructions; or rather I should say it’s about the process of producing and distributing artifacts by means of social constructions. Artifacts like houses, cars, computers, and toasters; social constructions like money, bonds, deeds, policies, rights, corporations, and governments. Of course, there are also services, which are not quite artifacts since they stop existing when we stop doing them—though, crucially, not when we stop believing in them; your waiter still delivered your lunch even if you persist in the delusion that the lunch is not there. And there are natural resources, which existed before us (and may or may not exist after us). But these are corner cases; mostly economics is about using laws and money to distribute goods, which means using social constructions to distribute artifacts.

Other very important social constructions include race and gender. Not melanin and sex, mind you; human beings have real, biological variation in skin tone and body shape. But the concept of a race—especially the race categories we ordinarily use—is socially constructed. Nothing biological forced us to regard Kenyan and Burkinabe as the same “race” while Ainu and Navajo are different “races”; indeed, the genetic data is screaming at us in the opposite direction. Humans are sexually dimorphic, with some rare exceptions (only about 0.02% of people are intersex; about 0.3% are transgender; and no more than 5% have sex chromosome abnormalities). But the much thicker concept of gender that comes with a whole system of norms and attitudes is all socially constructed.

It’s one thing to say that perhaps males are, on average, more genetically predisposed to be systematizers than females, and thus men are more attracted to engineering and women to nursing. That could, in fact, be true, though the evidence remains quite weak. It’s quite another to say that women must not be engineers, even if they want to be, and men must not be nurses—yet the latter was, until very recently, the quite explicit and enforced norm. Standards of clothing are even more obviously socially-constructed; in Western cultures (except the Celts, for some reason), flared garments are “dresses” and hence “feminine”; in East Asian cultures, flared garments such as kimono are gender-neutral, and gender is instead expressed through clothing by subtler aspects such as being fastened on the left instead of the right. In a thousand different ways, we mark our gender by what we wear, how we speak, even how we walk—and what’s more, we enforce those gender markings. It’s not simply that males typically speak in lower pitches (which does actually have a biological basis); it’s that males who speak in higher pitches are seen as less of a man, and that is a bad thing. We have a very strict hierarchy, which is imposed in almost every culture: It is best to be a man, worse to be a woman who acts like a woman, worse still to be a woman who acts like a man, and worst of all to be a man who acts like a woman. What it means to “act like a man” or “act like a woman” varies substantially; but the core hierarchy persists.

Social constructions like these ones are in fact some of the most important things in our lives. Human beings are uniquely social animals, and we define our meaning and purpose in life largely through social constructions.

It can be tempting, therefore, to be cynical about this, and say that our lives are built around what is not real—that is, fiction. But while this may be true for religious fanatics who honestly believe that some supernatural being will reward them for their acts of devotion, it is not a fair or accurate description of someone who makes comparable sacrifices for “the United States” or “free speech” or “liberty”. These are social constructions, not fictions. They really do exist. Indeed, it is only because we are willing to make sacrifices to maintain them that they continue to exist. Free speech isn’t maintained by us saying things we want to say; it is maintained by us allowing other people to say things we don’t want to hear. Liberty is not protected by us doing whatever we feel like, but by not doing things we would be tempted to do that impose upon other people’s freedom. If in our cynicism we act as though these things are fictions, they may soon become so.

But it would be a lot easier to get this across to people, I think, if folks would stop saying idiotic things like “science is a social construction”.

Will China’s growth continue forever?

PNRJ current events, development economics , , , , , , , , ,

July 23, JDN 2457958

It’s easy to make the figures sound alarming, especially if you are a xenophobic American:

Annual GDP growth in the US is currently 2.1%, while annual GDP growth in China is 6.9%. At markte exchange rates, US GDP is currently $18.6 trillion, while China’s GDP is $11.2 trillion. If these growth rates continue, that means that China’s GDP will surpass ours in just 12 years.

Looking instead at per-capita GDP (and now using purchasing-power-parity, which is a much better measure for standard of living), the US is currently at $53,200 per person per year while China is at $14,400 per person per year. Since 2010 US per-capita GDP PPP has been growing at about 1.2%, while China’s has been growing at 7.1%. At that rate, China will surpass the US in standard of living in only 24 years.

And then if you really want to get scared, you start thinking about what happens if this growth continues for 20, or 30, or 50 years. At 50 years of these growth rates, US GDP will just about triple; but China’s GDP would increase by almost a factor of thirty. US per-capita GDP will increase to about $150,000, while China’s per-capita GDP will increase all the way to $444,000.

But while China probably will surpass the US in total nominal GDP within say 15 years, the longer-horizon predictions are totally unfounded. In fact, there is reason to believe that China will never surpass the US in standard of living, at least within the foreseeable future. Sure, some sort of global catastrophe could realign the world’s fortunes (climate change being a plausible candidate) and over very long time horizons all sorts of things can happen; but barring catastrophe and looking within the next few generations, there’s little reason to think that the average person in China will actually be better off than the average person in the United States. Indeed, while that $150,000 figure is actually remarkably plausible, that $444,000 figure is totally nonsensical. I project that in 2065, per-capita GDP in the US will indeed be about $150,000, but per-capita GDP in China will be more like $100,000.

That’s still a dramatic improvement over today for both countries, and something worth celebrating; but the panic that the US must be doing something wrong and China must be doing something right, that China is “eating our lunch” in Trump’s terminology, is simply unfounded.

Why am I so confident of this? Because, for all the proud proclamations of Chinese officials and panicked reports of American pundits, China’s rapid growth rates are not unprecedented. We have seen this before.

Look at South Korea. As I like to say, the discipline of development economics is basically the attempt to determine what happened in South Korea 1950-2000 and how to make it happen everywhere.

In 1960, South Korea’s nominal per-capita GDP was only $944. In 2016, it was $25,500. That takes them from solidly Third World underdeveloped status into very nearly First World highly-developed status in just two generations. This was an average rate of growth of 6.0%. But South Korea didn’t grow steadily at 6.0% for that entire period. Their growth fluctuated wildly (small countries tend to do that; they are effectively undiversified assets), but also overall trended downward.

The highest annual growth rate in South Korea over that time period was an astonishing 20.8%. Over twenty percent per year. Now that is growth you would feel. Imagine going from an income of $10,000 to an income of $12,000, in just one year. Imagine your entire country doing this. In its best years, South Korea was achieving annual growth rates in income comparable to the astronomical investment returns of none other than Warren Buffett (For once, we definitely had r < g). Even if you smooth out over the boom-and-bust volatility South Korea went through during that period, they were still averaging growth rates over 7.5% in the 1970s.

I wasn’t alive then, but I wouldn’t be surprised if Americans back then were panicking about South Korea’s growth too. Maybe not, since South Korea was and remains a close US ally, and their success displayed the superiority of capitalism over Communism (boy did it ever: North Korea’s per capita GDP also started at about $900 in 1960, and is still today… only about $1000!); but you could have made the same pie-in-the-sky forecasts of Korea taking over the world if you’d extrapolated their growth rates forward.

South Korea’s current growth rate, on the other hand? 2.9%. Not so shocking now!

Moreover, this is a process we understand theoretically as well as empirically. The Solow model is now well-established as the mainstream neoclassical model of economic growth, and it directly and explicitly predicts this sort of growth pattern, where a country that starts very poor will initially grow extremely fast as they build a capital base and reverse-engineer technology from more advanced countries, but then over a couple of generations their growth will slow down and eventually level off once they reach a high level of economic development.

Indeed, the basic reason is quite simple: A given proportional growth is easier to do when you start small. (There’s more to it than that, involving capital degradation and diminishing marginal returns, but at its core, that’s the basic idea.)

I think I can best instill this realization in you by making another comparison between the US and China: How much income are we adding in absolute terms?

US per-capita GDP of $53,200 is growing at 1.2% per year; that means we’re adding $640 per person per year. China per-capita GDP of $14,400 is growing at 7.1% per year; that means they’re adding $1,020 per year. So while it sounds like they are growing almost six times faster, they’re actually only adding about 40% more real income per person each year than we are. It’s just a larger proportion to them.

Indeed, China is actually doing relatively well on this scale. Many developing countries that are growing “fast” are actually adding less income per person in absolute terms than many highly-developed countries. India’s per capita GDP is growing at 5.8% per year, but adding only $340 per person per year. Ethiopia’s income per person is growing by 4.9%—which is only $75 per person per year. Compare this to the “slow” growth of the UK, where 1.0% annual growth is still $392 per person per year, or France, where “stagnant” growth of 0.8% is still $293 per person per year.

Back when South Korea was growing at 20%, that was still on the order of $200 per person per year. Their current 2.9%, on the other hand, is actually $740 per person per year. We often forget just how poor many poor countries truly are; what sounds like a spectacular growth rate still may not be all that much in absolute terms.

Here’s a graph (on a log scale) of GDP per capita in the US, Japan, China, and Korea, from World Bank data since 1960. I’d prefer to use GDP PPP, but the World Bank data doesn’t go back far enough.

As you can see, there is a general pattern of growth at a decreasing rate; it’s harder to see in China because they are earlier in the process; but there’s good reason to think that they will follow the same pattern.

If anything, I think the panic about Japan in the 1990s may have been more justifiable (not that it was terribly justified either). As you can see on the graph, in terms of nominal GDP per capita, Japan actually did briefly surpass the United States in the 1990s. Of course, the outcome of that was not a global war or Japan ruling the world or something; it was… the Nintendo Wii and the Toyota Prius.

Of course, that doesn’t stop people from writing news articles and even publishing economic papers about how this time is different, not like all the other times we saw the exact same pattern. Many Chinese officials appear to believe that China is special, that they can continue to grow at extremely high rates indefinitely without the constraints that other countries would face. But for once economic theory and economic data are actually in very good agreement: These high growth rates will not last forever. They will slow down, and that’s not such a bad thing. By the time they do, China will have greatly raised their standard of living to something very close to our own. Hundreds of millions of people have already been lifted out of abject poverty; continued growth could benefit hundreds of millions more.

The far bigger problem would be if the government refuses to accept that growth must slow down, and begins trying to force impossible levels of growth or altering the economic data to make it appear as though growth has occurred that hasn’t. We already know that the People’s Republic of China has a track record of doing this sort of thing: we know they have manipulated some data, though we think only in small ways, and the worst example of an attempt at forcing economic growth in human history was in China, the so-called “Great Leap Forward” that killed 20 million people. The danger is not that China will grow this fast forever, nor that they will slow down soon enough, but that they will slow down and their government will refuse to admit it.

Several of the world’s largest banks are known to have committed large-scale fraud. Why have we done so little about it?

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July 16, JDN 2457951

In 2014, JPMorgan Chase paid a settlement of $614 million for fraudulent mortgage lending contributing to the crisis; but this was spare change compared to the $16.5 billion Bank of America paid in settlements for their fradulent mortgages.

In 2015, Citibank paid $700 million in restitution and $35 million in penalties for fraudulent advertising of “payment protection” services.

In 2016, Wells Fargo paid $190 in settlements for defrauding their customers with fake accounts.

Even PayPal has paid $25 million in settlements over abuses of their “PayPal Credit” system.
In 2016, Goldman Sachs paid $5.1 billion in settlements over their fraudulent sales of mortgage-backed securities.
But the worst offender of course is HSBC, which has paid $2.5 billion in settlements over fraud, as well as $1.9 billion in settlements for laundering money for terrorists. The US Justice Department has kept their money-laundering protections classified because they’re so bad that simply revealing them to the public could result in vast amounts of criminal abuse.
These are some of the world’s largest banks. JPMorgan Chase alone owns 8.0% of all investment banking worldwide; Goldman Sachs owns 6.6%; Citi owns 4.9%; Wells Fargo 2.5%; and HSBC 1.8%. That means that between them, these five corporations—all proven to have engaged in large-scale fraud—own almost one-fourth of all the world’s investment banking assets.

What shocks me the most about this is that hardly anyone seems to care. It’s seen as “normal”, as “business as usual” that a quarter of the world’s investment banking system is owned by white-collar criminals. When the issue is even brought up, often the complaint seems to be that the government is being somehow overzealous. The Economist even went so far as to characterize the prosecution of Wall Street fraud as a “shakedown”. Apparently the idea that our world’s most profitable companies shouldn’t be able to launder money for terrorists is just ridiculous. These are rich people; you expect them to follow rules? What is this, some kind of democracy?

Is this just always how it has been? Has corruption always been so thoroughly infused with finance that we don’t even know how to separate them? Has the oligarchy of the top 0.01% become so strong that we can’t even bring ourselves to challenge them when they commit literal treason? For, in case you’ve forgotten, that is what money-laundering for terrorists is: HSBC gave aid and comfort to the enemies of the free world. Like “freedom” and “terrorism”, the word “treason” has been so overused that we begin to forget its meaning; but one of the groups that HSBC gladly loaned money to is an organization that has financed Hezbollah and Al-Qaeda. These are people that American and British soldiers have died fighting against, and when a British bank was found colluding with them, the penalty was… a few weeks of profits, no personal responsibility, and not a single day of prison time. The settlement was in fact less than the profits gained from the criminal enterprise, so this wasn’t even a fine; it was a tax. Our response to treason was to impose a tax.

And this of course was not the result of some newfound leniency in American government in general. No, we are still the nation that imprisons 700 out of every 100,000 people, the nation with more prisoners than any other nation on Earth. Our police officers still kill young Black men with impunity, including at least three dozen unarmed Black men every year, many of them for no apparent reason at all. (The precise number is still unknown, as the police refuse to keep an official database of all the citizens they kill.) Decades of “law and order” politicians promising to stop the “rising crime” (that is actually falling) have made the United States very close to a police state, especially in poor neighborhoods that are primarily inhabited by Black and Hispanic people. We don’t even have an especially high crime rate, except for gun homicides (and that because we have so many guns, also more than any other nation on Earth). We are, if anything, an especially vindictive society, cruel, unforgiving, and violent towards those we perceive as transgressors.

Except, that is, when the criminals are rich. Even the racial biases seem to go away in such circumstances; there is no reasonable doubt as to the guilt of O.J. Simpson or Bill Cosby, but Simpson only ended up in prison years later on a completely unrelated offense, and after Cosby’s mistrial it’s unclear if he’ll ever see any prison time. I don’t see how either man could have been less punished for his crimes had he been White; but can anyone seriously doubt that both men would be punished more had they not been rich?

I do not think that capitalism is an irredeemable system. I think that, in themselves, free markets are very useful, and we should not remove or restrict them unnecessarily. But capitalism isn’t supposed to be a system where the rich can do whatever they want and the poor have to accept it. Capitalism is supposed to be a system where everyone is free to do as they choose, unless they are harming others—and the rules are supposed to be the same for everyone. A free market is not one where you can buy the right to take away other people’s freedom.

Is this just some utopian idealism? It would surely be utopian to imagine a world where fraud never happens, that much is true. Someone, somewhere, will always be defrauding someone else. But a world where fraud is punished most of the time? Where our most powerful institutions are still subject to the basic rule of law? Is that a pipe dream as well?

This is a battle for the soul of America

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July 9, JDN 2457944

At the time of writing, I just got back from a protest march against President Trump in Santa Ana (the featured photo is one I took at the march). I had intended to go to the much larger sister protest in Los Angeles, but the logistics were too daunting. On the upside, presumably the marginal impact of my attendance was higher at the smaller event.

Protest marches are not a common pastime of mine; I am much more of an ivory-tower policy wonk than a boots-on-the-ground political activist. The way that other people seem to be allergic to statistics, I am allergic to a lack of statistics when broad claims are made with minimal evidence. Even when I basically agree with everything being said, I still feel vaguely uncomfortable marching and chanting in unison (and constantly reminded of that scene from Life of Brian). But I made an exception for this one, because Trump represents a threat to the soul of American democracy.

We have had bad leaders many times before—even awful leaders, even leaders whose bad decisions resulted in the needless deaths of thousands. But not since the end of the Civil War have we had leaders who so directly threatened the core institutions of America itself.

We must keep reminding ourselves: This is not normal. This is not normal! Donald Trump’s casual corruption, overwhelming narcissism, authoritarianism, greed, and utter incompetence (not to mention his taste in decor) make him more like Idi Amin or Hugo Chavez than like George H.W. Bush or Ronald Reagan. (Even the comparison with Vladimir Putin would be too flattering to Trump; Putin at least is competent.) He has personally publicly insulted over 300 people, places, and things—and counting.

Trump lies almost constantly, surrounds himself with family members and sycophants, refuses to listen to intelligence briefings, and personally demeans and even threatens journalists who criticize him. Every day it seems like there is a new scandal, more outrageous than the last; and after so long, this almost seems like a strategy. Every day he finds some new way to offend and undermine the basic norms of our society, and eventually he hopes to wear us down until we give up fighting.

It is certainly an exaggeration, and perhaps a dangerous one, to say that Donald Trump is the next Adolf Hitler. But there are important historical parallels between the rise of Trump and the rise of many other populist authoritarian demagogues. He casually violates democratic norms of civility, honesty, and transparency, and incentivizes the rest of us to do the same—a temptation we must resist. Political scientists and economists are now issuing public warnings that our democratic institutions are not as strong as we may think (though, to be fair, others argue that they are indeed strong enough).

It was an agonizingly close Presidential election. Even the tiniest differences could have flipped enough states to change the outcome. If we’d had a better voting system, it would not have happened; a simple plurality vote would have elected Hillary Clinton, and as I argued in a previous post, range voting would probably have chosen Bernie Sanders. Therefore, we must not take this result as a complete indictment of American society or a complete failure of American democracy. But let it shake us out of our complacency; democracy is only as strong as the will of its citizens to defend it.

The right (and wrong) way to buy stocks

PNRJ financial advice, heuristics and biases , , , , , , , , , , , , , , , , , , ,

July 9, JDN 2457944

Most people don’t buy stocks at all. Stock equity is the quintessential form of financial wealth, and 42% of financial net wealth in the United States is held by the top 1%, while the bottom 80% owns essentially none.

Half of American households do not have any private retirement savings at all, and are depending either on employee pensions or Social Security for their retirement plans.

This is not necessarily irrational. In order to save for retirement, one must first have sufficient income to live on. Indeed, I got very annoyed at a “financial planning seminar” for grad students I attended recently, trying to scare us about the fact that almost none of us had any meaningful retirement savings. No, we shouldn’t have meaningful retirement savings, because our income is currently much lower than what we can expect to get once we graduate and enter our professions. It doesn’t make sense for someone scraping by on a $20,000 per year graduate student stipend to be saving up for retirement, when they can quite reasonably expect to be making $70,000-$100,000 per year once they finally get that PhD and become a professional economist (or sociologist, or psychologist or physicist or statistician or political scientist or material, mechanical, chemical, or aerospace engineer, or college professor in general, etc.). Even social workers, historians, and archaeologists make a lot more money than grad students. If you are already in the workforce and only expect to be getting small raises in the future, maybe you should start saving for retirement in your 20s. If you’re a grad student, don’t bother. It’ll be a lot easier to save once your income triples after graduation. (Personally, I keep about $700 in stocks mostly to get a feel for what it is like owning and trading stocks that I will apply later, not out of any serious expectation to support a retirement fund. Even at Warren Buffet-level returns I wouldn’t make more than $200 a year this way.)

Total US retirement savings are over $25 trillion, which… does actually sound low to me. In a country with a GDP now over $19 trillion, that means we’ve only saved a year and change of total income. If we had a rapidly growing population this might be fine, but we don’t; our population is fairly stable. People seem to be relying on economic growth to provide for their retirement, and since we are almost certainly at steady-state capital stock and fairly near full employment, that means waiting for technological advancement.

So basically people are hoping that we get to the Wall-E future where the robots will provide for us. And hey, maybe we will; but assuming that we haven’t abandoned capitalism by then (as they certainly haven’t in Wall-E), maybe you should try to make sure you own some assets to pay for robots with?

But okay, let’s set all that aside, and say you do actually want to save for retirement. How should you go about doing it?

Stocks are clearly the way to go. A certain proportion of government bonds also makes sense as a hedge against risk, and maybe you should even throw in the occasional commodity future. I wouldn’t recommend oil or coal at this point—either we do something about climate change and those prices plummet, or we don’t and we’ve got bigger problems—but it’s hard to go wrong with corn or steel, and for this one purpose it also can make sense to buy gold as well. Gold is not a magical panacea or the foundation of all wealth, but its price does tend to correlate negatively with stock returns, so it’s not a bad risk hedge.

Don’t buy exotic derivatives unless you really know what you’re doing—they can make a lot of money, but they can lose it just as fast—and never buy non-portfolio assets as a financial investment. If your goal is to buy something to make money, make it something you can trade at the click of a button. Buy a house because you want to live in that house. Buy wine because you like drinking wine. Don’t buy a house in the hopes of making a financial return—you’ll have leveraged your entire portfolio 10 to 1 while leaving it completely undiversified. And the problem with investing in wine, ironically, is its lack of liquidity.

The core of your investment portfolio should definitely be stocks. The biggest reason for this is the equity premium; equities—that is, stocks—get returns so much higher than other assets that it’s actually baffling to most economists. Bond returns are currently terrible, while stock returns are currently fantastic. The former is currently near 0% in inflation-adjusted terms, while the latter is closer to 16%. If this continues for the next 10 years, that means that $1000 put in bonds would be worth… $1000, while $1000 put in stocks would be worth $4400. So, do you want to keep the same amount of money, or quadruple your money? It’s up to you.

Higher risk is generally associated with higher return, because rational investors will only accept additional risk when they get some additional benefit from it; and stocks are indeed riskier than most other assets, but not that much riskier. For this to be rational, people would need to be extremely risk-averse, to the point where they should never drive a car or eat a cheeseburger. (Of course, human beings are terrible at assessing risk, so what I really think is going on is that people wildly underestimate the risk of driving a car and wildly overestimate the risk of buying stocks.)

Next, you may be asking: How does one buy stocks? This doesn’t seem to be something people teach in school.

You will need a brokerage of some sort. There are many such brokerages, but they are basically all equivalent except for the fees they charge. Some of them will try to offer you various bells and whistles to justify whatever additional cut they get of your trades, but they are almost never worth it. You should choose one that has a low a trade fee as possible, because even a few dollars here and there can add up surprisingly quickly.

Fortunately, there is now at least one well-established reliable stock brokerage available to almost anyone that has a standard trade fee of zero. They are called Robinhood, and I highly recommend them. If they have any downside, it is ironically that they make trading too easy, so you can be tempted to do it too often. Learn to resist that urge, and they will serve you well and cost you nothing.

Now, which stocks should you buy? There are a lot of them out there. The answer I’m going to give may sound strange: All of them. You should buy all the stocks.

All of them? How can you buy all of them? Wouldn’t that be ludicrously expensive?

No, it’s quite affordable in fact. In my little $700 portfolio, I own every single stock in the S&P 500 and the NASDAQ. If I get a little extra money to save, I may expand to own every stock in Europe and China as well.

How? A clever little arrangement called an exchange-traded fund, or ETF for short. An ETF is actually a form of mutual fund, where the fund purchases shares in a huge array of stocks, and adjusts what they own to precisely track the behavior of an entire stock market (such as the S&P 500). Then what you can buy is shares in that mutual fund, which are usually priced somewhere between $100 and $300 each. As the price of stocks in the market rises, the price of shares in the mutual fund rises to match, and you can reap the same capital gains they do.

A major advantage of this arrangement, especially for a typical person who isn’t well-versed in stock markets, is that it requires almost no attention at your end. You can buy into a few ETFs and then leave your money to sit there, knowing that it will grow as long as the overall stock market grows.

But there is an even more important advantage, which is that it maximizes your diversification. I said earlier that you shouldn’t buy a house as an investment, because it’s not at all diversified. What I mean by this is that the price of that house depends only on one thing—that house itself. If the price of that house changes, the full change is reflected immediately in the value of your asset. In fact, if you have 10% down on a mortgage, the full change is reflected ten times over in your net wealth, because you are leveraged 10 to 1.

An ETF is basically the opposite of that. Instead of its price depending on only one thing, it depends on a vast array of things, averaging over the prices of literally hundreds or thousands of different corporations. When some fall, others will rise. On average, as long as the economy continues to grow, they will rise.

The result is that you can get the same average return you would from owning stocks, while dramatically reducing the risk you bear.

To see how this works, consider the past year’s performance of Apple (AAPL), which has done very well, versus Fitbit (FIT), which has done very poorly, compared with the NASDAQ as a whole, of which they are both part.

AAPL has grown over 50% (40 log points) in the last year; so if you’d bought $1000 of their stock a year ago it would be worth $1500. FIT has fallen over 60% (84 log points) in the same time, so if you’d bought $1000 of their stock instead, it would be worth only $400. That’s the risk you’re taking by buying individual stocks.

Whereas, if you had simply bought a NASDAQ ETF a year ago, your return would be 35%, so that $1000 would be worth $1350.

Of course, that does mean you don’t get as high a return as you would if you had managed to choose the highest-performing stock on that index. But you’re unlikely to be able to do that, as even professional financial forecasters are worse than random chance. So, would you rather take a 50-50 shot between gaining $500 and losing $600, or would you prefer a guaranteed $350?

If higher return is not your only goal, and you want to be socially responsible in your investments, there are ETFs for that too. Instead of buying the whole stock market, these funds buy only a section of the market that is associated with some social benefit, such as lower carbon emissions or better representation of women in management. On average, you can expect a slightly lower return this way; but you are also helping to make a better world. And still your average return is generally going to be better than it would be if you tried to pick individual stocks yourself. In fact, certain classes of socially-responsible funds—particularly green tech and women’s representation—actually perform better than conventional ETFs, probably because most investors undervalue renewable energy and, well, also undervalue women. Women CEOs perform better at lower prices; why would you not want to buy their companies?

In fact ETFs are not literally guaranteed—the market as a whole does move up and down, so it is possible to lose money even by buying ETFs. But because the risk is so much lower, your odds of losing money are considerably reduced. And on average, an ETF will, by construction, perform exactly as well as the average performance of a randomly-chosen stock from that market.

Indeed, I am quite convinced that most people don’t take enough risk on their investment portfolios, because they confuse two very different types of risk.

The kind you should be worried about is idiosyncratic risk, which is risk tied to a particular investment—the risk of having chosen the Fitbit instead of Apple. But a lot of the time people seem to be avoiding market risk, which is the risk tied to changes in the market as a whole. Avoiding market risk does reduce your chances of losing money, but it does so at the cost of reducing your chances of making money even more.

Idiosyncratic risk is basically all downside. Yeah, you could get lucky; but you could just as well get unlucky. Far better if you could somehow average over that risk and get the average return. But with diversification, that is exactly what you can do. Then you are left only with market risk, which is the kind of risk that is directly tied to higher average returns.

Young people should especially be willing to take more risk in their portfolios. As you get closer to retirement, it becomes important to have more certainty about how much money will really be available to you once you retire. But if retirement is still 30 years away, the thing you should care most about is maximizing your average return. That means taking on a lot of market risk, which is then less risky overall if you diversify away the idiosyncratic risk.

I hope now that I have convinced you to avoid buying individual stocks. For most people most of the time, this is the advice you need to hear. Don’t try to forecast the market, don’t try to outperform the indexes; just buy and hold some ETFs and leave your money alone to grow.

But if you really must buy individual stocks, either because you think you are savvy enough to beat the forecasters or because you enjoy the gamble, here’s some additional advice I have for you.

My first piece of advice is that you should still buy ETFs. Even if you’re willing to risk some of your wealth on greater gambles, don’t risk all of it that way.

My second piece of advice is to buy primarily large, well-established companies (like Apple or Microsoft or Ford or General Electric). Their stocks certainly do rise and fall, but they are unlikely to completely crash and burn the way that young companies like Fitbit can.

My third piece of advice is to watch the price-earnings ratio (P/E for short). Roughly speaking, this is the number of years it would take for the profits of this corporation to pay off the value of its stock. If they pay most of their profits in dividends, it is approximately how many years you’d need to hold the stock in order to get as much in dividends as you paid for the shares.

Do you want P/E to be large or small? You want it to be small. This is called value investing, but it really should just be called “investing”. The alternatives to value investing are actually not investment but speculation and arbitrage. If you are actually investing, you are buying into companies that are currently undervalued; you want them to be cheap.

Of course, it is not always easy to tell whether a company is undervalued. A common rule-of-thumb is that you should aim for a P/E around 20 (20 years to pay off means about 5% return in dividends); if the P/E is below 10, it’s a fantastic deal, and if it is above 30, it might not be worth the price. But reality is of course more complicated than this. You don’t actually care about current earnings, you care about future earnings, and it could be that a company which is earning very little now will earn more later, or vice-versa. The more you can learn about a company, the better judgment you can make about their future profitability; this is another reason why it makes sense to buy large, well-known companies rather than tiny startups.

My final piece of advice is not to trade too frequently. Especially with something like Robinhood where trades are instant and free, it can be tempting to try to ride every little ripple in the market. Up 0.5%? Sell! Down 0.3%? Buy! And yes, in principle, if you could perfectly forecast every such fluctuation, this would be optimal—and make you an almost obscene amount of money. But you can’t. We know you can’t. You need to remember that you can’t. You should only trade if one of two things happens: Either your situation changes, or the company’s situation changes. If you need the money, sell, to get the money. If you have extra savings, buy, to give those savings a good return. If something bad happened to the company and their profits are going to fall, sell. If something good happened to the company and their profits are going to rise, buy. Otherwise, hold. In the long run, those who hold stocks longer are better off.