On March 15 I wrote (That's right I am starting the first post of this blog by quoting myself...are you sure you still want to read this?):
“Keep in mind that pandemic predictions are meant to be the opposite of a self-fulfilling prophecy. If people believe a dire prediction and respond, then their response could stem the tide, making the prediction appear foolish in hindsight. That is not a sign that the prediction was wrong; it is a sign that the response was effective. However, if we ignore those predictions, then they could very well come true and the consequences will be devastating.”
It is hard to believe that was 5 weeks ago! Somehow it simultaneously feels like yesterday and an eternity ago.
Well here we are in mid-April and there is good news and bad news. The good news is that for the most part the worst-case scenarios have not come to fruition. The bad news is that people are already starting to use the flawed reasoning I was warning about.
Here is an excerpt from a recent article that I read:
“When the lockdowns began last month, we were told that if we didn’t stay home our hospitals would be overwhelmed with coronavirus patients…But with the exception of New York City, the overwhelming surge of coronavirus patients never really appeared—at least not in the predicted numbers, which have been off by hundreds of thousands.” The author, who is an editor at an online magazine called The Federalist (a magazine I do NOT endorse), goes on to conclude: “The overarching narrative that we all bought into, that unless we stayed home and ‘flattened the curve’ our hospitals would be inundated, and if your kids got sick there would be no beds available to treat them, has turned out to be false.” And later he proposes that “Now that we know our hospitals aren’t going to be overrun by COVID-19 cases, governors and mayors should immediately reverse course and begin opening their states and communities for business.”
Notice the flaw in this line of reasoning.
1. Experts say that if we don’t stay home there will be a surge.
2. We stayed home.
3. There was no surge.
4. Therefore staying home was unnecessary.
Is that sound reasoning? Let’s apply the same line of reasoning to a more familiar scenario: wearing a seatbelt.
1. Experts say that if you don’t wear a seatbelt, you could be ejected from a car in an accident.
2. You wore a seatbelt.
3. You got in an accident and were not ejected from the car.
4. Therefore wearing a seatbelt was unnecessary.
In both cases the conclusion is nonsense. The whole point of the precautionary measures was to prevent a bad outcome. It makes no sense to conclude that because the bad outcome never materialized the precautions were unnecessary. That turn of events is entirely consistent with the precautions doing exactly what they were supposed to do!
Now, I am not claiming that this proves that lockdowns work. You could make an equally flawed argument in the other direction.
1. We stayed home.
2. There was no surge.
3. Therefore staying home prevented the surge.
That is an example of the classic blunder of confusing correlation with causation. Two quantities may be correlated (i.e. changes in one coincide with changes in the other) without one causing the other. The most famous example of this is ice cream sales and shark attacks. Both seem to rise in the summer and fall in the winter. Does ice cream cause shark attacks? Of course not. Both are related to (caused by?) another variable: weather. We enjoy eating ice cream and swimming in shark-infested waters more when it is warm and sunny!
So, we cannot necessarily include that the surge didn’t happen because of the lockdowns either. Demonstrating causality is notoriously difficult unless you can run a controlled experiment (which might be a hard sell when it involves giving someone a potentially deadly virus). There are some clever methods for trying to infer causality from observational data, but they are a bit too complex to try to get into in a blog post.
The point is that it is hard to know what would have happened had we not implemented lockdowns. It is also hard to know how much of a difference lockdowns made over less restrictive alternatives like voluntary social distancing. Sadly, some people take that uncertainty, throw in some flowery language, questionable logic, and a sprinkle of cherry-picked data, and turn it into a (fictional) narrative that supports their agenda. I hope that most people will see through those deeply flawed arguments and take the time to evaluate them critically instead of accepting them or worse, passing them on through social media. The challenges we are facing are serious and the divisions in our country run deep. The last thing we need is more disinformation, dubious arguments and dishonest debate muddying the waters.