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interfluidity » 2020 » July

...Archive for July 2020

Dispersion causes discohesion

Dispersion causes discohesion. It is hard to have a cohesive, high-functioning, society when dispersion of individual outcomes — “inequality” — is high.

Some people argue that mobility is an answer to dispersion, that it’s okay, great even, to have extremely unequal outcomes as long as it is possible for people who begin poor to end up rich (and vice versa). I’ve argued against that before. This post will further explain why I think celebrating the combination of inequality and social mobility is a particularly dumb idea.

We’ll start with a simple, tragic fact. In a society where there is both a high dispersion of outcomes (income, wealth, status, whatever people aspire to) and a high degree of mobility, from most individuals’ perspective, it’s more profitable to engage in distributional conflict to advance within the distribution than to cooperate to help shift the distribution, without competing to improve ones own rank.

Let’s illustrate this with a some pictures.

The grey bell curve represents the distribution (of wealth, income, status, whatever) in a society with a high dispersion of outcomes. The cyan bell curve represents how that full distribution might advance over the course of one lifetime, if most members of the society worked cooperatively to increase the general Welfare. The trouble is, if there is social mobility in this society, individuals have an alternative strategy. Rather than cooperating to shift the bell curve, they can compete with one another for slots within the existing bell curve. I’ve illustrated the situation of a hypothetical modal person.

Competing for rank in the distribution is a zero-sum game, so a “representative agent” that formed its expectations by averaging all outcomes, or an individual agent whose “rational expectation” was formed by assuming its odds are as good or bad as anyone else’s, might conclude that the expected value of this strategy is zero. However, that strikes me as unrealistic. In societies that celebrate social mobility, individuals are encouraged to have optimistic expectations, to believe that with our hard work we can exploit our own talents to “get ahead”. Let’s imagine that’s so, and a substantial fraction of agents believes that by competing for a better position, they can advance by one standard deviation within the distribution (the red arrow labeled “Conflict“). Now suppose that the plausible rate of aggregate progress, holding ranks constant, even if we organized effectively and cooperatively, is smaller than a one-standard deviation shift (the green arrow labeled “Cooperate“). Then basically it will be individually rational for all “optimistic” agents to devote themselves to contesting their rank within the distribution, rather than cooperating to work in ways that would contribute to aggregate prosperity but might not improve their own rank. The more optimistic the society is, in the sense that people believe that individuals can get ahead through their own efforts, the smaller the share of people who will eschew contesting social rank in favor of cooperating to advance aggregate prosperity.

Now let’s run the same thought experiment for a less unequal society.

Nothing has changed except the standard deviation of the bell curves I have drawn, representing the dispersion or inequality of the population. Again, “optimistic” individuals believe that by contesting their ranks, they can advance one standard deviation in the distribution. However, because this distribution is narrower, that degree of advancement is less than the progress they could plausibly expect if they held their rank within the distribution, but they organized cooperatively to achieve aggregate gains. Contesting ones place in the distribution, rising up by pushing others down, is a dumb strategy relative to cooperating to achieve aggregate gains.

To riff on Eugene Debs, whether it makes sense to try to rise from the ranks or to rise with the ranks is endogenous to both the level of inequality in a society, and the perceived social mobility available to optimistic agents. In a very unequal society with a high degree of rags-to-riches optimism (whether objectively defensible or not), lots of people will choose zero-sum conflict over rank rather than positive-sum cooperation towards progress. You can resolve this problem in a couple of ways. If you want a society that is both functional and unequal, you can choose illiberalism. Once mobility is off the table, if people understand that contesting their social rank will be fruitless, perhaps even punished, then the only strategy with any payoff is to cooperate to advance aggregate welfare. Unequal, illiberal societies can be very functional, so long as they credibly promise that gains will be widely shared, rather than hoarded only by high ranks. Perhaps contemporary China is a rough approximation of this kind of society, though I don’t have much handle on perceptions of social mobility there.

My own strong values are liberal, so I’d prefer we retain a high degree of openness to social mobility, but diminish pathological inducement towards zero-sum conflict by limiting the dispersion of the distribution, by reducing inequality. I believe we really do have to choose. We can have inequality without liberalism (the path offered by Donald Trump’s Republican Party). We can have liberal, less unequal societies (the path highlighted by Scandinavian societies). Or we can try to sustain a liberal, very unequal society, and find ourselves beset by continual conflict over rank and position, relying on social pathology at the bottom of the distribution to justify outsize fortunes of the top. I don’t think this last choice, our current choice, can last very long. I don’t think it is intellectually coherent to be liberal but not egalitarian, at least relative to current levels of dispersion.

But, the “classical liberal” will remind us, there is an obvious rejoinder to all of this. I have treated competing to advance ones place within the distribution and cooperating to shift the full distribution forward as distinct, mutually exclusive strategies. Isn’t the whole point of capitalism, its core virtue, that an invisible hand transmutes competitive individualism into cooperative gain? Yes! Absolutely! But that doesn’t happen by magic, automatically.

Not all competition takes the form of competitive supply into open and contestable markets that economics textbooks tell us maximize output and eliminate markups. I think it’s particularly important to distinguish this kind of economic competition from tournament competition, whereunder people compete for a relatively fixed numbers of slots with high payouts. Too often in the United States we use “competition” as a broad, bland term to legitimate almost any sort of outcome. That is dumb. When warlords pummel one another’s villages until, finally, one of them gains supremacy, I think we’d all agree that is a hypercompetitive process. But, as the smoking wreckage attests, it is a negative-sum game, it is bad not good. Similarly, the tournament that selects admission into Harvard is certainly competitive, but when you add all the resources expended by the losers as well as winners into activities they would not have undertaken for personal development, that tournament is probably also negative-sum. If you have achieved a lucrative partnership at a top law firm, you have brutally competed for your entire career. But if you didn’t win that partnership, someone else would have. Your gain was someone else’s losses. The costs of these usually negative-sum tournaments may be somewhat offset by the virtue of putting the most talented people in places where they can do outsized good. But that depends on very particular circumstances. In a society where economic competition is far from perfect, where firms with outsize market power dominate to harvest outsize markups, individual prospects are largely determined by tournaments for positions within those dominant firms. A world like this is certainly “competitive”, but in a way that should lend it no legitimacy at all. The tournaments for lucrative slots are negative-sum internally, and the external effect of this form of organization is to curtail the textbook economic competition that might otherwise contribute to aggregate well-being.

The classical liberal isn’t wrong when she argues that the virtues of economic competition can undermine the case I’ve made above, can reconcile aggregate progress with an unequal distribution in a liberal society. But that it can do so doesn’t mean that it does, or is likely to, in practice. When we say markets civilize greed, we are acknowledging that greed needs to be civilized, that if it is not caged and channeled by certain kinds of institutions, it does harm. To reconcile competitive inequality and collective progress, we’d need markets that are perpetually contested, in which victory is always transient because anyone’s profit is everyone’s wide open opportunity. The world that we actually inhabit looks less and less like that. The more competitive behavior in an economy is characterized by tournaments, the less persuasive classical liberalism’s answer to reconciling competition with cooperation becomes. We revert to the world of our thought experiment. If we adopted some muscular version of antitrust, if we replaced patent monopolies with less destructive approaches to rewarding high-fixed-cost innovation, if we developed means of countering the market power engendered by technological network effects, maybe we could reconcile social mobility, high levels of inequality, and brisk improvement of aggregate welfare. But that would require designing and performing unusually excellent institutions. It would require sustaining those institutions over long periods of time, against continuing, earnest efforts by incumbents to undermine them.

Which again suggests we must limit inequality. Because when incumbents have very, very far to fall, it means they have a lot of power today, and extraordinary incentives to rig the game.

Breakup sex

Today I see people whose politics I largely share getting upset about things. Here are Briahna Joy Gray and David Sirota, upset that John Kasich may play a role in the Democratic National Convention. Here is Anand Giridharadas grappling with how to welcome the energy and support of the “Lincoln Project” without ceding power to the very same people who brought us the Iraq War, torture, and predatory mortgages and financial fraud.

The metaphor for how I think that “we” (for a suitably nebulous we) should deal with the 2020 election is “breakup sex”.

Our current relationship with the Democratic Party is intolerable. The people who run the institution do not share our values, at least not in any way that matches the urgency of the catastrophe our world has become. We’ve tried for two Presidential election cycles to reform the party from the inside, using the primary process, and not succeeded, both for reasons fair and foul. Yet the pathology of our first-past-the-post electoral system and the logic of Duverger’s tendency means it would harmful to do the natural thing and form our own political party. Under electoral systems like ours (which it should be among our highest priorities to change) splitting a broad coalition disempowers the entire coalition, handing elections and power to people whose interests and values are so far from our own we would never have been anywhere near a coalition with them. Within the Democratic Party our values are undermined, coopted, sacrificed on the alter of a cynical realism that the well-remunerated realists quietly prefer. If we split from the Democratic Party, we hand power to a coalition that is, at the moment, an unabashedly fascist death cult. Things are tough all over. This is intolerable. We have to find a way out.

I think there is a way out. A fair number of us, described sometimes as “Bernie or bust”, argue that we should withhold our support from the Democratic Party, despite electoral realities, unless they earn our support with candidates and platforms that represent us. Sometimes this is taken a principled stand, to be taken regardless of consequence. But often it is justified in game-theoretical terms: If institutional Democrats know that we are trapped, that we will always hold our noses and vote with them, then we will have no leverage in the party. We have to demonstrate a willingness to accept the short-term risk of spoiling elections in order, over the longer term, to gain bargaining power within the Democratic coalition so that our values and interests actually get represented.

There is a lot to be said for this view, but it is kneecapped when it is put into practice on individualized, atomized terms. Most of us, compelled by the logic of negative partisanship, hold our noses and vote for the “corporate Democrat” who we expect will betray us, but who will probably not murder us like the other guy might. Others vote for Jill Stein or Howie Hawkins, or don’t show up at the polls. The inconsistency dilutes the potential effectiveness of the strategy. If the goal is actually to wield power, our withholding or supplying votes must be a matter of coordinated, collective action rather than individualized expressive choice. We need a union that can credibly threaten to strike, not individuals some of whom rage quit.

So, breakup sex. I think, in this year of our lord 2020, we should actively, enthusiastically, passionately support the Democratic Party and the prototype institutional Democrat who leads its ticket. They always try to convince us that letting the other team win would be the end of the world, but this year the horde of rabid predators is pretty visible while they are crying wolf. As soon as the election has passed, I think we should form a distinct organization that would not be a political party in the sense of participating in our country’s deeply flawed public primary process, but that would, like a political party, sometimes moot its own candidates for public office and help get them placed on ballots (whether as organization representatives or notional independents). Sometimes is an important word in that description. Most of the time, it hopefully would not. The organization would simply endorse the Democratic party candidate, keeping whole the not-Republican coalition. But, if a high (supermajority) threshold of the membership decides that the Democrat would not represent our values effectively, that the risk of spoiling the election is acceptable given whoever the Republican would be and is outweighed by the possibility our better candidate might win, then we would run that candidate and organize on their behalf with energy and unconflicted enthusiasm. Defecting from the Democratic Party, when it makes sense, makes much more sense as a collective rather than individual choice.

This organization might only rarely run candidates but still have a salutary effect on our politics. A credible threat that the social democratic wing of the party might defect would change the kind of candidates the party would nominate under its everpresent “electability” fetish. The existence of such an organization would also incentivize Republicans not to nominate, say, pathological narcissists with inchoate tendencies towards authoritarianism and racial hierarchy. Republicans will understand that, if they nominate someone sufficiently mild and tweedle-dee-ish next to what might be portrayed as a corporate-Democrat tweedle-dum, the social democratic wing of the Democratic coalition might risk a split and hand them an advantage. The existence of a union of social democratic voters would create incentives for the Democratic Party to become more social-democratic, and for the Republican party to become saner. It’s win-win-win.

This is, of course, a second-best solution. Replacing our terrible first-past-the-post electoral system with sane alternatives would enable a diversity of proper political parties to contest elections on equal terms. But this is something we can just do, long before an uphill struggle can be won to get incumbent politicians to reform the system that exalts them.

We should start to build this organization, just after the election. In the meantime, until then, I think we should passionately support Joe Biden and whatever motherfucker has a D next to their name on November’s ballot. My view is that it’s not worth the trouble to be coy, to withhold support conditional on platform commitments or John Kasich not marring the Democrats’ stage. During a Biden administration, there will be a huge battle over who must be betrayed — corporations and donors, or us. For now, the best way to wage that fight is to be an indispensable part of this election’s coalition. Beginning in November 4th, we organize to credibly threaten to take our indispensable selves elsewhere if it is us who is betrayed.

We’re at the point in the relationship where I think we do have to leave, sort of. We can no longer remain an informal, disorganized “wing” of the Democratic Party contesting bizarrely constituted primaries under institutions whose leaders oppose and outmaneuver us. But we need to decamp smartly, in a way that strengthens the influence of our values rather than uselessly spoiling elections. And before we go, this election cycle, the sex should be unreserved and hot. Biden 2020, baby.

Social democracy and freedom

In 1962, Milton Friedman famously argued that liberal capitalism and political freedom go together, they are mutually reinforcing. Nowadays, for a lot of us Milton Friedman has become a kind of bogeyman, the false prophet of a catastrophic social experiment that has, after decades, left us immiserated and divided. But I have some sympathy. The basic structure of the argument is that however democratic a powerful central government might purport to be, it is a danger to freedom. Decentralized power plus change enacted via mutually beneficial exchange are more likely to produce positive progress and — perhaps more importantly — are less likely to feature some powerful class that, through error or malevolence, harms or abridges the rights and liberties of disfavored groups. Friedman writes:

Viewed as a means to the end of political freedom, economic arrangements are important because of their effect on the concentration or dispersion of power. The kind of economic organization that provides economic freedom directly, namely, competitive capitalism, also promotes political freedom because it separates economic power from political power and in this way enables the one to offset the other.

Capitalism and Freedom was written in the heyday of the Kuznets curve, which posited that extreme inequality was self-correcting and had largely already self-corrected in modern economies. Friedman celebrated moderate inequality, on the theory that a world with many captains of industry would have many and diverse philanthropists to whom partisans of unpopular causes could make their case and find sponsorship. The logic of the argument rests on the notion that capitalism preserves political diversity that cuts across the structure of wealth and power, so that any partisan, regardless of her politics, could find communities willing and able to celebrate or at least tolerate her, within which she could secure some livelihood and position.

There is an obvious critique of this from the left. Political diversity won’t cut across structures of wealth and power evenly. Humans, including fabulously wealthy humans, are quirky, so sure, there’ll be some Friedrich Engelses and Nick Hanauers. But the winners of an economic game by and large will promote views that celebrate and entrench the game they continually win. Quantities (of money) matter, and there’s lots more scope to make a living at Mercatus than at People’s Policy Project, for partisans willing to adjust their politics accordingly. Capitalism, then, buys the appearance of political diversity (every voice is in the room!), but puts a fat thumb on the scale for the interests of the wealthy and powerful.

Interestingly, though, despite (really because of) decades of Friedman-justified nonintervention into the operation of capitalist markets, the most strident complaints of nonfreedom now come from not from the economic left but the social right. Is “cancel culture” tyranny or itself free speech? Bret Stephens is a fun figure in this debate, because he has a history both of trying to get people disciplined for their speech and of complaining that conformism to the doctrines of “woke” social liberalism are grave threats to freedom of expression. Here’s Stephens today:

The more serious problem today comes from the left: from liberal elites who, when tested, lack the courage of their liberal convictions; from so-called progressives whose core convictions were never liberal to begin with; from administrative types at nonprofits and corporations who, with only vague convictions of their own, don’t want to be on the wrong side of a P.R. headache.

This has been the great cultural story of the last few years. It is typified by incidents such as The New Yorker’s David Remnick thinking it would be a good idea to interview Steve Bannon for the magazine’s annual festival — until a Twitter mob and some members of his own staff decided otherwise. Or by The Washington Post devoting 3,000 words to destroying the life of a private person of no particular note because in 2018 she wore blackface, with ironic intent, at a Halloween party. Or by big corporations pulling ads from Facebook while demanding the company do more to censor forms of speech they deem impermissible.

These stories matter because an idea is at risk. That’s the idea that people who cannot speak freely will not be able to think clearly, and that no society can long flourish when contrarians are treated as heretics.

That idea, old as Socrates, formerly had powerful institutional defenders, especially in the form of universities, news media, book publishers, free-speech groups and major philanthropies.

But those defenders are, on account of one excuse or another, capitulating to people who claim free speech for themselves (but not for others), who believe all the old patriarchal hierarchies must go (so that new “intersectional” hierarchies may arise), who are in a perpetual fervor to rewrite the past (all the better to control the future), and who demand cringing public apologies from those who have sinned against an ever-more radical ideological standard (while those apologies won’t save them from being fired).

David Karpf (whom Stephens tried to have disciplined for a mean joke) responds on Twitter:

This is a vision of free speech that collapses under minimal Socratic scrutiny. It’s a Freedom of speech that demands a safe space from all counterspeech — free speech for me but not for thee.

FedEx telling Dan Snyder to change the damn name [of the Washington Redskins] IS speech.

People pressuring FedEx to tell Snyder this are engaging in speech as well.

Protest actions are acts of speech, even if those protest actions are aimed at people who Bret Stephens identifies with.

That’s the rotten core of every “campus cancel culture” controversy.

You have the right to speak. You don’t have a right to a (paid) platform. And if people think your speech is bad, offensive, harmful, or dangerous, then THEY have just as much right to say speak as well.

This is an insight so mundane that it barely deserves mentioning. Free speech applies to everyone, even people who criticize Bret.

So who is right here? I say Milton Friedman is. “Free speech” stops being real, stops being a practicable ideal, once the consequences of unpopular expression are so great you’ll be banished from the communities you value and unable to earn a decent living. Both the woke and their discontents should be able to speak their piece, both a controversial talk and the angry protest it accumulates are important components of free speech. We want a society where — in practice, not just as a formal, legalistic matter — the public sphere can accommodate a wide range of expression, some of which each of us will find abhorrent.

But Friedman’s conjecture that capitalism plus a light-touch state would be an effective way to ensure this state of affairs was wrong. Because it was never really “capitalism”, in his argument, that protected political freedom. It was decentralization, a broad distribution of wealth and power largely uncorrelated with political commitments. And what we’ve discovered (as any Marxist would have predicted) is that laissez-faire-ish capitalism doesn’t deliver that at all. Instead it delivers accumulation and scarcity, both at individual and institutional levels. At an individual level, the Kuznet’s curve that was fashionable when Friedman wrote, that suggested inequality was a problem of the past under industrial capitalism, has completely broken down. We are back in the Gilded Age, or worse, in terms of inequality. If the consequence of unpopular speech is that a person falls from the upper-middle to something below the middle of the income distribution, that would have been tolerable in 1962 in a way it is not tolerable now. At an institutional level, the economy has consolidated since 1962. The elites who manage the winners of that consolidation and who benefit from entrenched monopoly have of necessity developed a strategies to defend the winner-take-all economy from democratic contestation. One strategy contemporary robber barrons have converged upon is to rebrand themselves as “progressive”, as forces of social good. They cynically and collectively choose what qualifies as virtuous in social affairs, and they garb themselves and give philanthropically to immunize themselves from attacks on their dominant and entrenched economic positions. Today it is Black Lives Matter. A decade ago it was “transformation of the world economy lift[ing] four people in China and India out of poverty and into the middle class” for every American it kicks out, which doesn’t play well anymore in Western democracies. It changes with the wind, Davos is like a fashion magazine. But at any given moment, there must be great and virtuous causes whose pursuit is not antithetical to continued domination by the already dominant. Dominant firms will brook no public dissent from the moment’s religion, as preaching that religion is essential to bewildering and misdirecting an immiserated public whose democratic power could, in theory, undo them.

It’s a bit, um, rich that Bret Stephens would complain about this from his perch at The New York Times, whose dominance of print news is unprecedented and growing. But perhaps it is understandable that he feels the chill. Elite positions like his are an ever-shrinking a game of musical chairs, lots of us would love his life and he wouldn’t love ours. If he (like his editor) were kicked out in a great public scandal, it’s not at all clear that he would land so well. Among elites, the stakes of this game of dangerous speech and righteous counterspeech have become enormously high. (Just ask Steve Salaita, Bret.) You can lose the sort of incomes most of us will never enjoy, and the sort of social place most of us will never experience, if your friends decide they have to sacrifice you in the name of the corporate virtue upon which you collectively depend.

So for those of us who really favor free expression, what is to be done? It’s not enough to adopt a legalistic, First Amendment version that shrugs when private actors censor, ban, and risk people’s livelihoods. It’s pure surrender to defer to Popper’s “paradox of tolerance” and say that it’s cool there’s an ever-shifting set of boundaries beyond which expression and therefore eventually thought can legitimately be punished, because some ideas are too dangerous, free society is too weak to tolerate them.

We should return to the wisdom of Milton Friedman, that political freedom is a structural matter, inextricable from economic arrangements. Friedman was wrong that light-touch capitalism would durably enshrine and protect the kind of structure conducive to political freedom (ht Chris Mealy). He probably was not wrong that versions of socialism that repose economic power in a unified economic hierarchy would be hostile to political freedom. Instead what is required is some system in which the economic stakes of unpopular speech are unlikely to be so horrible, because the distance between lives of the conformist elite and unwashed others is not so great. What is required is a system under which economic power is not consolidated among a few firms with a shared interest in sheltering their dominance, but where instead a diversity of thriving actors ensures that any weirdo can find prosperous communities that will at least tolerate, if not agree with, her views. Such a system might look a lot like capitalism with limited government, but the limits of government would expand somewhat from protecting property and enforcing contracts to providing generous universal (therefore nondiscriminatory) social benefits, raising the floor onto which one might fear to fall for speaking your mind. Such a system might design its corporate and tax law explicitly to promote competition and limit scale (rather than narrowly proscribing a few illegitimate tactics or effects for clever lawyers to work around) so that economic power is affirmatively widely distributed.

If there’s a name for this system, almost uniquely consistent with durable political freedom, I think it would be “social democracy”.

Update History:

  • 5-July-2020, 11:35 p.m. EDT: “…middle class’ for every American it kicks out, which…”; “…some ideas are too dangerous, and free society is too weak to tolerate them.”; “He probably is was not wrong that versions…”
  • 7-July-2020, 2:30 p.m. EDT: “banished from the communities you value and be unable to earn a decent living”
  • 13-July-2020, 2:30 p.m. EDT: “…lots of us would love a his life and he wouldn’t love ours…” (thanks Christian Peel)

Pandemic Diary 2020-07-02: Thymus theories

This post is pure conjecture. I’m not an immunologist or virologist or doctor, nor am I particularly informed in any of those fields. Still, I’ve been obsessed to the point of paralysis by the COVID pandemic, and I try to make sense of things. I offer this in hopes that people more informed than me will tell me why it’s full of shit, not because you should expect it should be right. (And, though it’s all probably wrong, I don’t think these ideas are original. I’m just giving order to thoughts gleaned from conversations in the ether.)

So. Here’s the “theory”. Recently evidence has emerged that T-cells play an important role in COVID recovery and immunity (ht Andy Slavitt). T-cells (as I understand things!) comprise a distinct though related line of defense from antibodies and the B-cells that produce those. The adaptive immune system, in my imagination, is like a mind that works to sense and remember invaders, and produce a response that must be carefully calibrated to repel them without causing too much “collateral damage” to the body. T-cells have a variety of roles in that mind, serving as repositories of memory and helping to coordinate the antibody response. But they also function as killers.

While antibodies mark and disable invaders floating around in your blood, killer T-cells “look inside” the cells of your body for untoward activity that might indicate infection. (Our cells have a kind of billboard upon which they display information about what they are up to, for these cells to observe.) When these killer T-cells decide they have sufficient evidence that a cell has gone rogue, they induce the cell to kill itself. This is a rough sort of justice. Antibodies are officer friendly, attacking bad guys but leaving the host unharmed. Killer T-cells are secret police, disappearing cells whose continued survival they deem not in the interest of the community. Killer T-cells attack not outsiders or invaders, but your own tissue, as a necessary evil to root out infection.

White blood cells are developed into T-cells by an organ called the thymus (after which they are named). One a priori clue that T-cells might have some role in COVID-19 is the age profile of the thymus. The thymus is most active in young children. It’s function declines with age, particularly after puberty, when it begins to “involute” or atrophy. While the thymus functions to some degree even in the elderly, it decays continuous over our lifespans, getting worse and worse. In male rodents, castration can slow this puberty-accelerated atrophy, and interestingly there’s evidence that human castrati have unusual longevity. (I still don’t recommend the procedure.)

Young children do very well with COVID-19, while the risk of a difficult outcome increases monotonically with age. This seems suggestive that the thymus and its T-cells might have a role in repelling the disease.

Two other pieces of evidence seem to fit. A recent French study found that asymptomatic close contacts of infected individuals often showed a T-cell response with no detectable antibody response in blood (ht TWiV, a great podcast!) What this might mean is that, in the very best kind of response to the infection, where you don’t get sick at all, your T-cells just quickly dispatch infected cells without much of an assist from antibodies at all. A Chinese study comparing the antibody response between asymptomatic and clinically-ill infecteds found, perhaps counterintuitively, a stronger antibody response among the sick than among those with no symptoms. Again, this seems consistent with the idea that a quick T-cell response is what’s most capable of forestalling the disease. Antibodies, in this conjecture, represent a second-best response, appearing if the T-cell response fails to make quick enough work of the infection.

It’s all about kinetics, about speed, in this “theory”. It’s a race. Bad outcomes come from a too-slow T-cell response. If your immune system develops COVID-19-attacking T-cells too slowly, you get a big but perhaps not-super-effective antibody response because nothing else is restraining the infection. Eventually, even older, slower thymuses do produce, but by the time they do, the infection may have run wild, so your own killer T-cells may end up deciding to attack a whole lot of your own tissue. This seems consistent with the observation that, once the infection becomes severe, immunosuppressants help prevent bad outcomes.

So that’s the conjecture, definitely overfitted to stuff I hear, probably bullshit, for what it’s worth.

What would be the implications if there were something to this? On the optimistic side, if the French study generalizes and an effective T-cell response often forestalls a discernible antibody response, that’s “immunity not reflected by serology“, which could mean that the infection fatality rates we’ve estimated from serology studies are overstated, and the disease may not be as commonly fatal as we think. On the less optimistic side, it means that an observed antibody response might not be strong evidence of vaccine effectiveness (e.g. here). It also calls into question the likelihood that convalescent plasma therapy and monoclonal antibodies will be great. Obviously, I hope these less happy implications are wrong.

Under this conjecture, if there were some way to accelerate thymus function or reverse its deceleration, that might be useful as a prophylactic. If thymus health can be evaluated more individually than “it gets worse with age”, maybe that would predict risk of a hard disease course. But it’s no great insight that bad health of an organ of the immune system would predict difficulty at repelling an infection, or that improving the health of such an organ might help. If there are thymus-stimulative treatments out there, probably they are already being tried.

These “thymus theories” are how I’m currently, tentatively, making sense of things for myself. But I’m not sure they are right, and even to the degree they might be, I’m not sure they buy us very much.