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This is not the right time for a pandemic. Not that there is a right time for a pandemic, but some times are definitely the wrong one. And no time is worse than when a nation is already in crisis, when trust in its leaders and itself is already low. A time when international relations are strained and internal strife widespread. Basically, if the social and moral fiber of a society are already being tested, the widespread fear of death at the hands of an invisible killer makes everything exponentially worse. Fortunately (or maybe unfortunately; it is very hard to tell at this point), history offers us a number of examples of when a plague arrived at the wrong time.

And none of these examples is better than the Great Plague of Athens. This deadly epidemic swept through the city in 430 B.C., the second year of the Peloponnesian War, claiming perhaps 100,000 lives and revealing in stark contrast the fissures and fractures in Athenian life and politics. The disease, largely believed by modern scholars to have been either typhus or typhoid, even killed the great Athenian general and statesman Pericles, his wife, and their sons, Paralus and Xanthippus. It was a disaster of epic proportions that altered not only the Peloponnesian War, but the whole of Greek, and consequently world, history. While the war would not end for nearly 26 years after the first wave of sickness, there is little doubt that the Great Plague changed the course of the war (being at least in part responsible for Athens’s defeat) and significantly shaped the peace that came afterward, planting the seeds that would weaken and then destroy Athenian democracy.

The best ancient account of the Great Plague, as for all of the Peloponnesian War, can be found in Thucydides’s History of the Peloponnesian War. Thucydides was an Athenian general exiled from Athens after being blamed for a disastrous defeat. In exile, he was able to travel freely in a way few could at the time, and so provides a unique firsthand account of this tumultuous period. He also fell victim to the Plague, though managed to survive, making his narration of the disease’s symptoms and sensations not only reliable, but quite visceral. Thucydides has been called the “father of political realism,” and his assessment of the Plague and its consequences bears out the honor. As few others have before or since, Thucydides understood the ways in which fear and self-interest, when they are submitted to, guide individual motives, and consequently the fate of nations.

Thus, in his account of the Great Plague, Thucydides looks frankly at the practical and moral weaknesses that the disease was able to exploit. He sharply notes how crowding in Athens, along with inadequate housing and sanitation, helped the disease spread more quickly and added to the number of casualties. He is aware that a lack of attention to important public-health and safety measures allowed the Plague to take root and made its effects much worse than they would have otherwise been.

But Thucydides is not concerned just with the ways in which poor urban planning caused the deaths of thousands of his countrymen. He is as much a moral critic as a political one. In his narration of the Plague’s devastation, he takes careful tally of instances of selflessness and courage, and those of selfishness and cowardice. It is clear that, for Thucydides at least, the death and suffering of a great epidemic (just like war) test the moral health of individuals and of societies. And a people who are not morally strong, when they become afraid, quickly slip into lawlessness and sacrilege: “For the violence of the calamity was such that men, not knowing where to turn, grew reckless of all law, human and divine.” What is also clear is that Thucydides does not think this collapse into immorality is simply a result of the Plague; rather, “Men who had hitherto concealed what they took pleasure in, now grew bolder.” To paraphrase Michelle Obama, pandemics don’t make your character; they reveal your character.

This is truly the danger, then, both for Athens and for us. And the consequences could not be greater. There is an argument, and a rather good one at that, that Athenian democracy was the great casualty of the Peloponnesian War. After Athens surrendered, a pro-Spartan oligarchy, known as the Thirty Tyrants, took control of the city. Though they were later ejected in a coup lead by Thrasybulus (a pro-democracy veteran of the Peloponnesian War who did not accept that the defeat of Athens meant the end of its democracy), Athenian democracy would never again recover its self-confidence and flirted with its own demise. This was the Athens that executed Socrates (whose own relationship with democracy and democratic principles was complicated). It was also the world in which Plato would write The Republic, the political treatise that became the template for totalitarianism for millennia. And when the end did eventually come for democracy in Athens, it was through the conquest of the Macedonian King Alexander (the Great, if you are curious), and Athens had provided him with his tutor, Aristotle, a man who had transmitted to his royal pupil his own anxieties around the excesses of democracy, particularly those born as a result of moral shortcomings among the people.

In the panic of the Great Plague, Athenians had experienced something about their world they could never purge and revealed something about themselves they could never forget. Gone were the days when they could comfortably see themselves in the words Pericles spoke in his famed funeral oration at the beginning of the Peloponnesian War, before the Plague carried him off to a less-than-glorious death: “We are not suspicious of one another … a spirit of reverence pervades our public acts; we are prevented from doing wrong by respect for the authorities and for the laws.”

The Great Plague tested this Athenian self-conception and found it wanting. Who people collectively believe they are is of the utmost importance, particularly in a democracy where the people are tasked with the grave responsibility of government. Self-government requires self-confidence. A democracy is unlikely to survive when the people have grown unsure of themselves and their leaders, laws, and institutions.

For nearly four years, the United States has experienced its own crisis of identity. Donald Trump’s presidency has been not just a series of political missteps and upheavals, an endless succession of low-burning fires, but a serious test (arguably the most serious test since the Civil War) of the foundational values and institutions that prop up the American experiment. But the appearance of the coronavirus is something altogether different. To begin with, the virus touches us all in a way that most of the Trump administration’s failures, for better or worse, do not. No amount of privilege or lack of interest can protect you from a pandemic. This is, by the way, something Thucydides noted: Diseases carry away both rich and poor, pious and impious. Tom Hanks is just as susceptible as you are. Literally no one can ignore this.

But perhaps more important, the virus has no mind. The Great Gatsby’s Daisy Buchanan was absolutely right when she noted that being careless is only a problem if you run into another careless person; that is, when you have an accident. President Trump has been substantially aided by the fact that he has not run into anyone quite as careless as he is. His most disastrous actions have been mitigated in no small part by other, cooler (or at least less volatile) heads. But a virus has no head. It is not just without reason, but without motive. It is truly only half alive. It has nothing to gain and nothing to lose. No sense of itself. No desire to live, something animals and even certain planets possess. This is why diseases and the threats they bring lay us all so bare. The only soul in the equation is our own. It is the ultimate test.

It is a test that thus far, Donald Trump and his administration are, unsurprisingly, failing. What remains to be seen is how the rest of us will do at this exam. The people of ancient Athens failed. Already in a time of war and upheaval, when people started to die from a disease they had never seen before, they abandoned the values that had been at the heart of their ability to govern themselves. They failed in their responsibility to one another because they no longer believed that it mattered. Everything that had come before the crisis and everything that happened during it conspired to give them this belief.

And this is what we must resist. The Great Plague of Athens wrote the first chapter in the end of Athenian democracy, but we do not need to accept its fate. The best thing about the past is that it can be our instructor, even if we seldom allow it to be. The ancient Greeks, by and large, believed that virtue was something you practiced. Like most everyone who lived before the philosopher Jean-Jacques Rousseau, Thucydides and his contemporaries did not believe that we are born good. We become good by choosing to do good. We become brave by choosing courage. We overcome the twin vices of self-interest and fear by actively rejecting them. The ancient Athenians failed to do this in the face of a plague and lost their democracy. Now the same choice is ours.

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