Are Westerners turning back into medieval peasants?

Technology works so well that we don't even feel like we have to believe in it anymore.

Photo by Democratizemedia via Wikimedia Commons

Advanced civilizations sometimes really do throw it all away. I recommend reading the book Lost Enlightenment, which is about how the golden age of Islamic science and scholarship and literature gave way to centuries of religious fundamentalism and backwardness. During the Ming and Qing dynasties, China turned its back on exploration, refused to import Western technologies, and generally de-emphasized science; centuries of economic stagnation and military weakness followed.

These are useful examples, but they’re all from the premodern period, where cutting-edge science and technology didn’t make a huge difference in people’s standard of living; most people were farmers living on the edge of subsistence. But around 200 years ago, technology really started to matter, and living standards began to skyrocket in a way they never had in history. Thanks to technology, humanity is now about 20 times richer on average than we were two centuries ago, and the number keeps going up:

For a civilization to turn its back on algebra in 1100 or on spring clocks in 1800 was certainly foolish. But for a civilization in 2025 to turn its back on the technologies that took our species from indigent peasants to modern standards of living would be just unfathomably insane.

And yet that is exactly what I now see Western civilization doing. In the U.S., the Anglosphere, and Europe, there are simultaneous backlashes against a number of key technologies that have either made the modern world what it is, or promise to make it even wealthier. These include:

• vaccines

• solar and wind power

• batteries

• AI

• software platforms

• anti-obesity drugs

• lab-grown meat

• self-driving cars

• air conditioning

I’m a well-known techno-optimist. Here was a manifesto I wrote about why technology is (usually) a good thing:

Thoughts on techno-optimism

And here’s an essay I wrote about why the creation of industrial modernity — which depends crucially on technology — is by far the most important accomplishment of humankind:

The elemental foe

In past years, I would write a techno-optimist post at the start of the year, gushing about all the marvels that are coming our way — here are the ones for 2021, 2022, 2023, and 2024. But this year I didn’t write one, because it seemed like America was generally turning away from techno-optimism, toward a dark, reactionary Luddism. I can still write a list of inventions to get excited about, but I feel like I’ll be setting myself up for disappointment when the general reaction is fear, cynicism, and superstition.

So instead, here’s a post about how the West is turning its back on the light of technology — the very thing that made it great in the first place.

The American right vs. the germ theory of disease

The thing that inspired this post — and the header image at the top — is the American right’s turn against vaccines, so let’s start with those.

The chief villain of this story, of course, is RFK Jr., who spent most of his political career as an antivax kook on the left, and was only embraced by Trump in a strategic alliance in 2024. Here’s a video from 2023 in which RFK told a podcast interviewer that the polio vaccine “killed many, many more people” than polio ever did.

That is, of course, complete nonsense. The polio vaccine is incredibly safe; the worst recorded incident of a defective vaccine, in the 1950s, killed a total of 10 people, and the total number of documented deaths ever resulting from the polio vaccine is no more than a couple dozen. In a typical year before the introduction of the vaccine, about 1,000 Americans died of polio every year:

The drop to zero, of course, coincides with the introduction of polio vaccines in 1955, which rapidly defeated the disease.

But this is very far from the kookiest anti-science thing that RFK Jr. has uttered. In his writings, he has expressed doubt about the germ theory of disease itself, and embraced a version of an ancient, discredited theory of disease called “miasma theory”. Ars Technica reports:

[RFK] wrote an entire section on [the germ theory of disease] in his 2021 book vilifying Fauci, titled The Real Anthony Fauci. The section is titled "Miasma vs. Germ Theory," in the chapter "The White Man's Burden."…He writes: "'Miasma theory' emphasizes preventing disease by fortifying the immune system through nutrition and by reducing exposures to environmental toxins and stresses."…

Kennedy contrasts his erroneous take on miasma theory with germ theory, which he derides as a tool of the pharmaceutical industry and pushy scientists to justify selling modern medicines. The abandonment of miasma theory, Kennedy bemoans, realigned health and medical institutions to "the pharmaceutical paradigm that emphasized targeting particular germs with specific drugs rather than fortifying the immune system through healthy living, clean water, and good nutrition."

According to Kennedy, germ theory gained popularity, not because of the undisputed evidence supporting it, but by "mimicking the traditional explanation for disease—demon possession—giving it a leg up over miasma."

Miasma theory? Seriously??? One X user referred to RFK’s ideas as “actual, honest-to-god medieval peasant beliefs”, and he isn’t wrong. The discovery that germs cause disease — and the subsequent development of vaccines, antibiotics, and sanitation to combat germs — was one of the fundamental break points that lifted humanity out of medieval conditions. In 1900, around 0.8% of all Americans were killed every year by infectious disease; today, in a typical year, it’s about a hundred times lower than that:

Source: CDC

RFK is already putting his medieval peasant theories into practice, canceling federal support for mRNA research that promises to turn cancer from a death sentence into a manageable condition:

Did RFK just take away your cancer treatment?

To his credit, Donald Trump has broken with his HHS secretary on the vaccine issue:

"I think you have to be very careful when you say that some people don't have to be vaccinated," Trump said…"They're just, pure and simple — they work," he added. "They're not controversial at all. And I think those vaccines should be used."

But although Trump’s power over the GOP is great, it’s not infinite. Despite Trump promoting the Covid vaccines that his first administration pioneered, the American right was eventually dominated by the antivax movement, leading to a large number of unnecessary deaths among conservatives.

Now, the antivax turn in the GOP is far bigger than RFK. The state of Florida is ending all vaccine mandates for schoolchildren. This won’t only harm kids whose parents choose not to vaccinate them; it will also endanger kids whose parents do vaccinate them. This is because vaccines work via herd immunity; vaccines aren’t 100% effective, but if everyone or almost everyone gets vaccinated, transmission gets halted because vaccines are effective enough that viruses can’t keep spreading.

If just 7% of parents don’t vaccinate their kids for measles, herd immunity against measles will be impossible, and lots of vaccinated kids will get measles too.¹ This is why we have vaccine mandates — by going unvaccinated, antivaxers aren’t just placing themselves and their own kids in danger, but everyone else around them as well.

Already, measles is starting to make a comeback in America, as a result of antivax superstition. There have been over 1400 cases this year so far — not a huge number yet, but growing alarmingly. If vaccine mandates are scrapped in red states, those numbers will continue to climb.

Slowly, the American right is turning into a movement against the germ theory of disease, and only bad can come of it.

Fighting the future