My kids and I have loved the musical Hamilton since its music was first released a few songs at a time. At one point, it seemed that my daughter had the entire music book memorized. One of the most memorable parts of the musical is the song “One Last Time.” In the song, President George Washington announces his decision not to run for a third term, over the objections of Alexander Hamilton, his Treasury Secretary. The song’s catchiness is a musical echo of just how notable it was when the real Washington made the decision to leave office. By that point in his career, he was seen by almost everyone in the young United States as by far the preeminent figure of the age, and could have kept serving, could even have made himself king. The fact that he did not, that he willingly relinquished power after two terms in office, was a decision both striking and celebrated. He has been compared to Cincinnatus, the Roman statesman who, after assuming the role of dictator to manage a military crisis, gave up power and returned to his farm once victory had been won.

Washington’s choice to give up power ranks high among his achievements not just because of what it said about his character, but because of the legitimacy it conferred on American institutions. Had he stayed, the system would have become all about him, and while he may have continued to do good in office, it would have come at the expense of the very institutions he spent his life helping to build. By leaving, and assuring a peaceful transition of power, he helped assure these institutions would remain strong and enjoy the collective buy-in of the people; a necessary condition for the functioning of a healthy republic.

Public health now finds itself at a similar crossroads with respect to power. We have amassed substantial power through our efforts to address the COVID crisis. This has been something of a change for us. In the past, it was not uncommon to hear complaints that public health is sometimes neglected, that its recommendations to policymakers and the public can fall on deaf ears. The pandemic reversed this. Notwithstanding the polarization that has kept a vocal faction of the population at odds with the recommendations of health authorities, we are in a moment when public health is more influential than it has ever been. And with the arrival of vaccines and signs that the pandemic has started to wane, this moment may well be ending. COVID itself is likely to remain with us in some form, as an endemic threat. But the emergency of COVID, the crisis of the pandemic year—its days are numbered.

When the Black Death struck Europe, it turned society upside down. The scale of the mortality—possibly up to a quarter of the population died from the plague—transformed economic systems, inflected religious thought, upended old institutions, and created space for new ones to emerge. It struck at the heart of the feudal system, which had long been the defining economic feature of the Middle Ages. For the first time, peasants no longer had to accept the terms dictated to them by the lords for whom they labored. With the population decimated, there were fewer people to work; those who remained were able to use their new leverage to demand better pay and conditions. Meanwhile, with the established authorities powerless to stop the spread of the disease, people began to imagine new approaches to scientific, political, and spiritual questions, paving the way for the currents of thought which would inform the Renaissance, a period which would, in turn, provide much of the intellectual grounding for the Age of Enlightenment.

It is significant that a pandemic would play a role in birthing these intellectual movements. The philosophies which emerged and were refined after the Middle Ages provided many of the values we now use to support health, and which have helped us to address the current pandemic, COVID-19. Centrally, these values are reason, the scientific method, and the pursuit of progress as a common goal worth striving toward. It was during the Enlightenment that our means of understanding the world shifted towards the collection of empirical data, and away from uncritical acceptance of revealed truths or articles of faith. This still serves as the template for scientific inquiry, shaping everything from our understanding of the socioeconomic determinants of health, to the research which has delivered a COVID vaccine.

There is an old joke, variations of which have long circulated. It goes like this: there once was a farmer whose cows had stopped producing milk. The farmer tried everything but could not manage to solve the problem. She tried altering the cows’ diet, she tried putting them in a new pasture, she tried enlisting the help of the local vet—all with no success. Finally, she took one of the cows to a world-renowned university located in her state. The university was home to some of the brightest contemporary minds; surely, they could help fix her malfunctioning livestock? The professors were indeed willing to help, leaping at the chance to tackle a difficult challenge. They agreed to examine the cows and apply their know-how to finding a way to return the herd to milk production. They spent weeks on the problem, making calculations, running various milk-production models, and consulting with researchers at other universities. When they had finished, the farmer returned to hear what they had come up with. Had they solved the problem? “Yes,” said the lead researcher. “We have found a surefire way to increase milk production. First let us assume we have spherical cows in a vacuum.”