 Good morning Hank, it's Tuesday. So there's this moment in the cartoon He-Man and the Masters of the Universe where the villain Skeletor says I can write a book about what you don't know! Now it turns out that Skeletor did not invent this colloquialism, but he did introduce it to me. And of course Skeletor's plans were always foiled by something he didn't know, but he was right about there being a lot I don't know. Like, there's a lot about the present I'll never know, I'll never know what it's like to be fluent in French or to play soccer professionally or the mathematics underlying quantum computing. And I'll never know almost everything about the past, because from the political structure of the Indus Valley civilization to what I ate for breakfast on January 10th, 2011, almost all of history has gone unrecorded. So we'll never really know the answers to big questions like why humans transition to agriculture or the answers to small questions like why prehistoric cave paintings so rarely depicted human figures. We can make increasingly informed speculations about the past and those speculations can be productive and interesting and even help deepen our understanding of the past, but you'll never know. And in that sense, the past is sort of like the future because we can speculate about the future and we can even model the future in ways that can be super helpful, but we can't know. Like, I will never know what life is like for humans in the 22nd century. Here's the thing though, even when it comes to things we'll never know, we have to make guesses. And in fact, we make guesses all the time and what we try to do is make the best and most informed guesses. Like when Sarah and I were deciding to get married, we couldn't know what it would be like to live together for decades or to raise children together or to face loss together. We made the best guess we could and then honestly, we got very lucky. Or at least I got very lucky. And so whether I'm deciding what to study in school or how to spend an afternoon, but ultimately I'm making a guess about the future and the matrix I use to make those guesses has recently been, like, obliterated, which is part of what I find so dizzying and confounding about this historical moment. This is a slight tangent, but when I try to explain to people what uncontrolled mental illness feels like for me, I often say it's like having to get out of bed in the morning and get dressed and go through my day while feeling that at literally every step, the floor might collapse beneath me. I feel as if I cannot trust the floor and that if I fall through it, it will be like that Emily Dickinson poem and then a plank and reason broke and I dropped down and down and hit a world at every plunge. Anyway, these days it feels like the floor I count on to always be there is less secure than it used to be and, like, Skeletor really could write a book about what we don't know. We don't know if surviving COVID-19 leads to long-term immunity and we don't know the exact effectiveness of various mitigation strategies and we don't know how many people have had COVID-19 or how many people have died of it. Like in the 2009 H1N1 flu pandemic, there were 18,631 laboratory confirmed deaths, but later studies found that at least 150,000 people and perhaps as many as half a million actually died from the pandemic. Now, we're doing a better job of tracking COVID-19 deaths, but our statistics are still really incomplete. And so we don't know most of what we need to know. But there have been many failures with COVID-19, failures of preparation, failures of political leadership, failures of the systems we count on to distribute information and goods and services, but I would argue the idea of expertise hasn't failed. We're just watching in real time how it happens, which is that our species starts out not even knowing there is a new virus spreading among humans and then over time learns the properties of that virus and then eventually progressively better strategies for containing it. We're already making better guesses about what the future may look like and how to make that future look less catastrophic and over time, through shared expertise, we will get better at treating and preventing this disease until one day someone writes a book about what we didn't know but did eventually find out. Hank, I'll see you on Friday.