Sickness changes the way we actually think

You wake up with a sore throat. In 2015, you’d probably grab some antihistamines, knowing the cold would pass in a few days. In 2020, you’d reach for the thermometer with dread, wondering if this was Covid.

But four thousand years ago, that same sore throat meant something entirely different. You’d need both a remedy-man with his herbs and a priest to determine “which of the thousands of pestering demons, always lurking in the corners of the world, has taken up residence in you,” historian Susan Wise Bauer writes in “The Great Shadow: A History of How Sickness Shapes What We Do, Think, Believe, and Buy” (St. Martin’s Press; Jan. 28).

Our evolving theories about what makes us sick haven’t just changed medicine, Bauer argues in her sweeping history. They’ve shaped civilization itself, influencing our religions, political systems, consumer habits, prejudices, and even our understanding of the universe.

“As we investigated the causes and cures of sickness within us, we began to change our views of the universe outside,” Bauer writes. 

In ancient Greece, when people believed illness stemmed from humoral imbalance, “we became obsessed with equilibrium and symmetry.” 

Much later, in the late nineteenth century, when scientists proved that germs carried disease, “we created an antiseptic culture,” complete with “separate drinking fountains and lavatories for those who carried ‘different’ sorts of germs.”

Most disturbingly, epidemic disease has repeatedly provided cover for humanity’s darkest impulses, particularly antisemitism.

The pattern crystallized during the Black Death. When bubonic plague erupted in 1346, it killed at least 25 million Europeans in just seven years, roughly a third of the population. Medieval physicians, working within Hippocratic humoral theory, struggled to explain why people of different constitutions all died the same way. The result was poison theory: the belief that deadly substances had entered the air, spread by earthquakes, planetary alignments, or human action.

That last possibility demanded a culprit. In 1348, physician Alfonso de Cordoba proposed that the plague came from three sources: the stars, disturbances of the earth, and a third “brought about by ‘artifice,’ or the evil workings of men,” Bauer writes. An evildoer, he suggested, could brew poison in a glass vessel and smash it, releasing a vapor that killed anyone it touched.

To Cordoba’s contemporaries, the identity of these poisoners seemed obvious. “Jews, bad and disloyal,” wrote French poet Guillaume de Machaut, had poisoned “the wells, the rivers, and the fountains.” Across Europe, Jews were tortured into confessing and entire neighborhoods were burned, families dying inside their homes. Even Pope Clement VI’s condemnation failed to stop the violence. The pogroms permanently reshaped European Jewish life, driving surviving communities eastward toward regions less invested in anti-Christian conspiracies.

The same logic resurfaced centuries later with deadlier efficiency. Under the Nazis, disease rhetoric became policy. Posters warned that “Jews, Lice, and Typhus” went together, and public health officials described Jews as parasites threatening the German body politic. Zyklon B, first developed as a delousing pesticide, became the tool of genocide.

Covid-19 produced another surge of antisemitism.  Iran’s state media claimed the virus was a Zionist bioweapon. Then-presidential candidate Robert F. Kennedy Jr. announced in 2023, in a video exclusively obtained by The Post, that “Covid-­19 is targeted to attack caucasians and black people. The people who are most immune are Ashkenazi Jews and Chinese.” Studies found antisemitic content online in France and Germany surged as much as fourteenfold during the pandemic.

“There is a straight line from the imaginary Jewish well-poisoners of the fourteenth century, to Covid-19 as a Jewish-sponsored bioweapon,” Bauer writes, with absurdities like “Jewish-controlled space lasers igniting wildfires in California falling somewhere in between.”

Disease fear has fostered suspicion of other groups over the years. In the late nineteenth and early twentieth centuries, immigrants were routinely framed as biological threats, slurred for outbreaks they didn’t cause. Tuberculosis was widely blamed on Jews, polio on Italians, and cholera on the Irish.

That impulse to locate invisible danger didn’t stop with conspiracies. Starting in the 1920s, as fear of pandemics like polio and Spanish flu gripped the world, Bauer writes, we began to “develop a Tupperware-enclosed, plastic-wrapped, disposable world.” Food once handled openly was sealed behind cellophane. Products were marketed as “sanitary” and “pure” precisely because they were untouched and meant to be thrown away. Disposability became a moral good, visible proof that science had tamed contamination.

In recent decades, it seemed that, for a time, we were moving beyond dated ideas around illness. But Bauer warns that we’re regressing.

The old theories about disease — divine punishment, humoral imbalance, atmospheric poison — haven’t vanished. “They linger on,” she writes. “Vaccine-denying becomes fashionable, homeopathic remedies and magnetic therapies are embraced, energy healing prospers.”

We like to believe we’ve evolved. Bauer’s history suggests we’re still sitting on that roof, terrified and praying for deliverance — just with fancier tools.

We once believed we had conquered infectious disease. Now, “we realize viruses might have the upper hand after all.”