Why Does Everyone Hate Rats?

Hey there, it’s Stephen Dubner. This year will mark a pair of anniversaries for us, and even though I ignore most anniversaries, these two have got their hooks in me. It has been 20 years since Steve Levitt and I published Freakonomics, and it’s been 15 years since I started Freakonomics Radio. So we are thinking about making some kind of anniversary episode, and I want to know if you have anything to share. Maybe it’s a story about how you were influenced or inspired by something from Freakonomics; maybe it’s some kind of memory or coincidence that you’d like to tell us about. Whatever it is: send us an email or a voice memo, whichever you prefer; our address is radio@freakonomics.com. Thanks in advance for that, and as always, thanks for listening.

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In the fall of 2022, a new job listing was posted on a New York City government website. “The ideal candidate,” the listing read, “is highly motivated and somewhat bloodthirsty, determined to look at all solutions from various angles, including data collection, technology innovation  and wholesale slaughter.” What kind of government job requires “wholesale slaughter”? Here is the man responsible for this listing.

Eric ADAMS: Rats do something to traumatize you, and I hate rats.

That is Eric Adams, the mayor of New York City.

ADAMS: If you walk down the block and a rat runs across your foot, you never forget it. Every time you walk down that block, you relive that.

As you may have heard, Adams was indicted last year on five federal criminal charges, including bribery and wire fraud — although, in a remarkable departure from legal precedent, the Trump administration Justice Department just ordered those charges dismissed. Through it all, the mayor’s anti-rat fervor has been undiminished:

ADAMS: Fighting crime, fighting inequality, fighting rats.

ADAMS: Public enemy number one, many of you don’t know, are rats. 

ADAMS: If you not scared of rats, you are really my hero.

And that job that was posted on NYC.gov — that was Eric Adams searching for his hero. Who turned out to be this person.

Kathy CORRADI: I was certainly taken aback. I mean, the job posting itself got a lot of fanfare.

Stephen DUBNER: I just want to read it to you verbatim. The job posting called for someone with a, quote, “swashbuckling attitude, crafty humor, and a general aura of badassery.”

CORRADI: Yeah. 

DUBNER: Is that you? 

CORRADI: I guess! Those are not words I’d necessarily include in my 150 characters. 

DUBNER: But come on. It sounds like you fit pretty well. 

CORRADI: Yeah, thank you. 

And that swashbuckling badass is:

CORRADI: Kathy Corradi. I’m the citywide Director of Rodent Mitigation for the City of New York, also known as the Rat Czar.

DUBNER: And how do you like that title, the Rat Czar?

CORRADI: Yeah, it’s good. My take is, the more people are talking about this topic, the better it is for the work we’re doing. 

New York and many other cities have seen a rise in their rat populations, especially during Covid, and now they are fighting back. But is “wholesale slaughter” really the way to go? That is one of the many rat questions that I am eager to answer over the next few episodes. The brown rat — also known as Rattus norvegicus — is one of the most reviled animals in the world.

Bethany BROOKSHIRE: We really hate them. We hate their success because their success feels like our failure. 

We’ll hear the details of New York’s rat-mitigation plan:

CORRADI: There’s a whole 99-page-report about how we’re going to do that.

But we’ll also hear from rat lovers:

Julia ZICHELLO: Eventually, because you’re feeding it, because it’s a little bit lovely, you end up feeling some warmth towards it.

And what you might call rat exonerators:

Ed GLAESER: Blaming the rat is pretty much, you know, game over in terms of the rat’s global reputation.

And let’s not forget the rat as cultural icon:

Jan PINKAVA: This is a story about a rat who wants to become a chef. Everyone laughs. Everyone gets it. You’re sold.

Are you sold?

I’m going to take that as a yes. Our three-part series on rats begins now.

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CORRADI: Rat mitigation is complicated. It’s looking at the forest and the trees at the same time. 

That, again, is New York City’s rat czar, Kathy Corradi.

CORRADI: Really, when it comes down to rats, what we’re talking about is an animal that lives in such close proximity to humans, and that’s why we have such a focus on them. 

DUBNER: I understand that your relationship with rats goes back pretty far, to when you were a kid growing up in New York. I understand that you circulated a petition in your neighborhood to get rid of some rats. Is that true? 

CORRADI: It is true. I grew up in a house that was abutting railroad tracks. And what you need to know about rats — a little quick and dirty here — is they need a place to live and they need food to eat. So, any space that’s not getting ongoing maintenance and can have overgrown brush or weeds, things of that nature, provides ideal habitat for them to burrow and create their nest. And that’s what we had behind my house. With the encouragement of my mom and our neighbor, we circulated a petition to get the local train company to take care of that harborage condition and address the rats.

DUBNER: Did it work? 

CORRADI: It did, yeah. You know, they cleaned the area. But the hard thing about rats is, one time doesn’t solve. That’s why it makes it such a challenging issue.

Corradi wound up getting an undergraduate degree in biology and a master’s in urban sustainability; she taught elementary school for a while and then she took a job in New York City’s Department of Education, in their sustainability office.

CORRADI: How I got tuned into rat mitigation work was through that role. We ran zero-waste programming, and because garbage and rats go hand in hand, my team was tasked with rat mitigation on the waste side for public schools. So, I was out and about to 120 different school buildings. Talking with facility staff. How do we manage our waste better? Talking with staff, students, and principal about waste-sorting behaviors and how we can make cleaner waste streams — less access to food sources for rats. The key to pest management — any pest management, first and foremost, is sanitation. 

Most people, when they think about sanitation, generally do not think of New York City. There are many things to love about this place, many things worth admiring. But let’s be honest: it’s not a particularly clean city. Trash on the sidewalks is a thing, especially food wrappers and big bags of restaurant trash. For a population of rats, all that food waste represents something like paradise. And how big is New York’s rat population?

CORRADI: There’s no census. So, if anyone is telling you a number, don’t believe it. 

DUBNER: I have seen an estimate by M&M Pest Control that puts the city’s rat population at around three million. Do you think that’s ballpark, or no chance? 

CORRADI: We’re not going to discuss a number. It’s kind of futile, and then anything you put out there then gets used as this watermark of, it was three million in 2024, someone else said it was eight million in 2006. It’s an unfair assessment. 

DUBNER: Now, let me go back to your official title, Director of Rodent Mitigation. Does that include squirrels, chipmunks, etc.? 

CORRADI: Squirrels, chipmunks, mice, all other rodents in the city. The main focus is on rats. There’s more of a community aspect when it comes to rats. They’re commensal, meaning they sit at the table with us.

DUBNER: What is that word you used, “commensal”?

CORRADI: Yes, commensal. 

DUBNER: What does that mean? 

CORRADI: It literally means like a seat at the table, meaning that they are thriving and existing because of the plate we’ve set for them in our urban spaces. Certainly the house mouse in a lot of regards is more successful, we can say, than a rat, in terms of how it breeds and how it occupies urban spaces and non-urban spaces. But rats are known for their ability to exploit and thrive where humans are densest. 

DUBNER: How do you think about rats versus the other rodents that are sometimes a problem? Rats look like bigger mice, sort of. And then there are squirrels, which most people seem to think are really cute, and people feed squirrels outside. I’ve never seen anybody feeding a rat outside. But is a rat just a squirrel with less attractive body hair?

CORRADI: In a way. And I would say, people are unintentionally feeding rats all the time across our city. Maybe they’re not throwing acorns or peanuts, but almost all of human behaviors in urban spaces end up feeding rats. 

DUBNER: How smart are rats? 

CORRADI: They are smart. I have not seen anything like a comparative I.Q. test for them — 

DUBNER: I mean, chipmunks always look pretty dumb to me. They’re super-cute, but they look dumb. Maybe I’m wrong. 

CORRADI: I would say, you know, in terms of how we gauge savviness, the rat is right up there. There’s more and more research coming out about them and empathy and laughing and altruism. 

DUBNER: Seriously? 

CORRADI: Yeah. And what we know is, in terms of adaptability to survive, there’s few species greater. They will avoid new things in their environment because they’re unsure if they’re harmful or helpful. There are stories of less-dominant rats being sent out to test a new food source and then being monitored to see if there’s ill effects. So, they are survivors. And I would say no one except humans exploits an urban space better.

Rats have been exploiting New York City’s urban space for at least a few hundred years. The ancestors of today’s rats are thought to have arrived in the 18^th century on ships from Europe. But in the historical rat timeline, that is still relatively recent; genetically, they date back to the time of dinosaurs. Today, there are two main species: the black rat, Rattus rattus, which likely originated in India and then the brown rat that we’re familiar with, Rattus norvegicus — “the Norway rat,” even though it did not originate in Norway. So why is it called that?

BROOKSHIRE: Ha ha! Because everybody who hates rats wants to name them after somebody they don’t like.

That is Bethany Brookshire.

BROOKSHIRE: So basically, the name stuck because somebody was picking a fight with Norway at the time. 

Brookshire is a science journalist with a Ph.D. in physiology and pharmacology. She recently published a book called Pests: How Humans Create Animal Villains. So you can see where her allegiance lies. Here is some more rat history:

BROOKSHIRE: Europe was very black rat-dominated until we think the 17th or 18th centuries, when we began to see the brown rat. That is native to what we think of as Mongolia. Rattus norvegicus ended up getting spread into Europe, and then with colonialism, it just went everywhere else because, rats and boats go together real good. Interestingly, people have not liked rats, but they didn’t necessarily consider them disgusting until about the 18th or 19th century. People didn’t like them because they were a problem of the food supply, right? They would get in and they would eat your food, and nobody wants that. But they weren’t considered to be disgusting in terms of they weren’t considered to carry disease for a very long time. The association of rats with disease is a relatively recent one.

DUBNER: How did that association come to be made, and how much does it intersect with the plague in Europe? 

BROOKSHIRE: It intersects with the plague, but not when you think it does. So, there have been three major pandemics of plague that we know of in recorded history. The first was the Plague of Justinian, which I believe was in the sixth century. The second was the Black Death, which was famous, and began in the 14th century. The third global pandemic of bubonic plague is now. It began in the 19th century, but it persists even now, actually, people every year in the United States, in Mongolia, and in Madagascar, in particular, get plague. 

To be clear, the plague persists today in very small numbers — just a few hundred reported cases a year, fewer than a dozen in the U.S. But this third wave of bubonic plague has done terrible damage over the past 100 years — in India, especially, during the early 20^th century, and in Vietnam during its war in the 1960s and 70s. The plague is caused by a bacterium known as:

BROOKSHIRE: Yersinia pestis. 

You see? It’s right there in the name: Yersinia pestis! The “yersinia” part comes from Alexandre Yersin , the first scientist to describe and culture these bacteria.

BROOKSHIRE: The bubonic plague is technically not a disease of humans. It is a disease of rats and fleas that happens to spill over into humans from time to time, with catastrophic effects.

And how much do we know about how the plague is spread?

BROOKSHIRE: What we do know is that fleas get Yersinia pestis, and then the bacteria forms a biofilm inside the esophagus of the rat flea, and the biofilm coats the esophagus so that the rat flea can’t swallow. It’s just biting and biting and biting and biting, but it can’t swallow anything, and it starves to death. And you start to feel really bad for the flea until you realize that everything it bites, it’s barfing up little bits of bacteria into the bite, spreading plague. So, that’s how plague is traditionally transmitted. 

Okay, and then how is plague spread between humans? For that, we’ll bring in another scientist.

STENSETH: In humans, it can be spread partly by ectoparasites, or by droplets — so, coughing. When you are having a cold, then that’s a way of transmission. 

That is Nils Christian Stenseth, a professor of ecology and evolution at the University of Oslo.

STENSETH: And for the last 25 years or so, I’ve been studying plague, Yersinia pestis, the bacterium that caused the Black Death. 

The Black Death tore through Europe in the mid-14^th century. It is hard to believe just how brutal it was.

STENSETH: The Black Death killed half of the European population in a year or two. The plague expresses itself in the human being in three different forms. The most common one is bubonic, where it’s swellings on the body. That may evolve into a pneumonic one that goes into the lung, and both might develop into a form that goes into the blood. If you’re infected by Yersinia pestis, if you don’t come to a doctor within four or five days, you can consider yourself being dead. 

During the Middle Ages, it was neither rats nor fleas who were thought to be responsible for the Black Death. Most of the blame was put on witches and Jews. But time, and science, eventually caught up with the rats — and if anything is going to give an animal species a bad reputation, it’s killing off half of Europe. The association between rats and plague remains strong today. In the opening credits of The Decameron, a new Netflix show set during the Black Death, a massive swarm of rats come together to spell out the title. And the recent remake of the film Nosferatu shows a pack of rats following the vampire, carrying the plague with them. But: were rats really responsible for the Black Death?

STENSETH: That’s the one that most people think are the right one. They are wrong. 

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One reason that rats are so despised is because they spread disease — the most famous instance being the Black Death, a pandemic of bubonic plague in the 14^th century that killed millions upon millions of Europeans. But scientists have recently challenged the claim that rats caused the Black Death — scientists including Nils Christian Stenseth at the University of Oslo. Challenging a claim like this is not a simple thing.

STENSETH: I usually say to my students that if you want to have enemies within science, study plague, because there are so many strong personalities, and there are so many different opinions, and they hate each other. 

The standard epidemiological model of the Black Death is that humans were exposed to the plague by rats who had been bitten by diseased fleas. But in 2018, Stenseth and his colleagues published a paper in the Proceedings of the National Academy of Sciences where they presented a different model. “Despite the historical significance of the disease,” they wrote, “the mechanisms underlying the spread of plague in Europe are poorly understood. While it is commonly assumed that rats and their fleas spread plague  there is little historical and archaeological support for such a claim.  “We show that human ectoparasites, like body lice and human fleas, might be more likely than rats to have caused the rapidly developing epidemics.” And what is Stenseth’s evidence that rats were not responsible for the Black Death? He and his coauthors looked at plague death rates from the 1300s to the 1700s, drawn from census records and historical accounts from cities including London, Barcelona, and Florence. Based on the velocity at which the plague spread in these places, Stenseth concluded, the human parasite model was much more likely than the rat parasite model.

STENSETH: It became very clear that the rat could not have played a major role in the spread of plague in Europe.

Ed GLAESER: One of the reasons why the rat-led plagues need to be slow is the rat has to die before the flea leaves the rat. So the flea stays on the rat as long as the rat’s alive. It’s only when the rat dies that the flea then hops to a human host.

And that is Ed Glaeser.

GLAESER: I’m the Fred and Eleanor Glimp Professor of Economics at Harvard University. 

That’s right, Glaeser is an economist — not an epidemiologist, or a biologist, or even a rat expert. But Glaeser is an expert in cities, which is where rats thrive and where disease spreads. And when we told him we were working on this rat series, he did some extra-credit reading.

GLAESER: I have now read enough in various academic journals that it seems like we have a consensus. This was not, by and large, rat-carried. They do seem to have played a critical role in the third bubonic plague explosion, although probably not in the first two.

DUBNER: So, having determined that, that there is at least some guilt of the rat in at least the third pandemic, but perhaps not the most famous, the Black Death, how would you say that the modern-day reputation of the rat has been affected by or informed by its implication in past disease-carrying? 

GLAESER: So blaming the rat is pretty much, you know, game over in terms of the rat’s global reputation. I think we should also just object to using the word “guilt” on rats. It’s not like they know what’s going on, and they’re dying too. I mean, let’s push the guilt where it belongs. Let’s go to Yersinia pestis itself. That’s where the evil lies. 

Glaeser is the author of a book called Triumph of the City: How Our Greatest Invention Makes Us Richer, Smarter, Greener, Healthier, and Happier. And the fact is that cities and rats seem to be an inevitable pairing. In the ruins of Pompeii, there were rats. To estimate the size of human populations in ancient cities, modern scientists use archeological evidence of rat populations.

GLAESER: When cities are at their best, they do enable people who are outsiders to thrive. It’s hard to imagine more of an outsider than a rat. 

DUBNER: To an economist, do rats present an obvious economic angle or maybe even multiple ones? 

GLAESER: Well, sure. Rats are, you know, they’re agents of usually negative externalities within cities, right? So they’re part of what enables diseases to spread across people. And consequently, they’re somewhat risky. I don’t know what positive things we get out of rats, but there probably are some in the same sense that, you know, the four-pest program that Mao followed, he thought getting rid of the sparrows was great. It turns out the sparrows kept the locusts under control, and without the sparrows the locusts went haywire and destroyed the crops, leading to a massive famine. 

DUBNER: Now, there was reportedly a big surge in rat population in New York City starting around 2020. I’m curious to know your thoughts on why? Obviously Covid is a factor to consider. There were in the aftermath of Covid the eruption of hundreds, maybe thousands, of outdoor dining sheds outside of restaurants. So I’m curious what you think of all that. 

GLAESER: Certainly Covid seems to have played some kind of a role. I mean, there were a whole bunch of city services that diminished because people were working from home or just weren’t going in and so forth. So I wouldn’t rule that out completely. Certainly changes in the food availability seem likely to be quite important. This would feel a lot better with some kind of measurement.

DUBNER: Now, if I recall correctly, you were born and raised in Manhattan. 

GLAESER: Indeed.

DUBNER: One could imagine that rats destroy or degrade the reputation of a city like New York. Do you put much stock in that argument? 

GLAESER: Oh, that seems a little bit far-fetched, to think that it’s such an important deal. I would say that what rats effectively do is they reduce the density level for people. And so they tend not to be density multipliers about the good things about cities which are enabling us to learn from one another. I’ve never heard of a rat carrying a message that was effectively interpreted. But they do seem to carry the negative stuff that we get from being close to one another. 

CORRADI: There’s an economic impact as well. So, thinking about damages to property. 

DUBNER: They like to chew wires, don’t they? 

CORRADI: They like to chew everything. 

That’s New York City rat czar Kathy Corradi.

CORRADI: That is literally their nature, to chew. They chew through holes in foundations. They can damage different food sources. You know, when we’re thinking about storage of food and grains and things of that nature. There’s a human cost in terms of public health, and then mental well-being. The mental effects on folks living in and around rats, that’s well-documented and being studied even more — stress, anxiety, depression. Documented, peer-reviewed papers saying this is real. There’s also a public health risk. Leptospirosis is one of the more famous illnesses associated with rats, and that’s due to a bacteria that they can transmit through their urine.  So there’s real public health concerns.

DUBNER: Although from what I’ve seen the last numbers, 2023, it looked like in New York City, 24 people were diagnosed with leptospirosis, the highest number of reported cases in a single year, but this is a city of over 8 million. So, that sounds like a pretty minor threat, no? 

CORRADI: I’m with you. It is certainly not the highest public health risk we have across, you know, our city or the globe. 

DUBNER: But that’s also people. I understand dogs get leptospirosis as well. And that, maybe, is a bigger problem for New Yorkers. 

CORRADI: Yes, dogs have a vaccine for leptospirosis. There’s other, I’d say unrealized potential public health risks when it comes to rats. So, a paper out of Columbia University studied rats across New York City and looked at the different lice, ticks, fleas they carried and also looked at different viruses, pathogens that were existing on their bodies, and found a bunch of novel viruses that were living on them. There’s always this threat when we’re talking about viruses, about their potential to mutate and jump host. Because rats are so close to us in where and how they live, that threat just gets higher and higher. 

Is the threat of disease really what this is about?

BROOKSHIRE: The fact that we’re so quick to blame the rat says a lot about us. 

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A rat is a rodent, a member of the order Rodentia, which contains over 2,000 species; nearly half of all mammals are rodents. They are famous for their gnawing ability, which is carried out by large pairs of upper and lower front incisors. Squirrels, mice, beavers, hamsters, prairie dogs, porcupines — they are all rodents. But it seems fair to say that rats are the most despised member of this order. Why? For that, let’s go back to Bethany Brookshire.

BROOKSHIRE: I’m the author of the 2022 book Pests: How Humans Create Animal Villains.

DUBNER: Talk about just the title itself, and what kind of work you’re asking that word, “pests,” to do. 

BROOKSHIRE: Oh, man. “Pests,” the word, does so much work in our society just in general. it has become a word for animals that are not where we want them to be. And that was one of the things that I became really fixated on is the fact that the animals that we hate are so subjective. The animals are just being animals. They’re about us. They’re about where we think animals belong, and what we think those animals should be doing. 

DUBNER: Do you think the rat has been unfairly tarnished — its reputation — over time, by having been associated with the Black Death? 

BROOKSHIRE: I don’t know that it’s been unfairly tarnished. I certainly think there was probably a place for it. I do think the fact that we’re so quick to blame the rat says a lot about us. Because the reality is the thing that causes most diseases in humans — like communicable diseases — is other humans, right? We are the major vectors of disease to each other. If we’ve learned from the COVID-19 pandemic, it is that. 

Humans do like to assign blame to other animals — but, as Brookshire points out, the blame can be assigned somewhat randomly. Consider the rabbit. The rabbit is not a rodent, although it used to be classified as such; today it’s considered a lagomorph, since it has four upper incisors, not two. For most people, the rabbit is thought of as — I believe the technical term is “cute.” It’s fluffy, it hops, it has facial features that kind of look like a human baby. If we think of rats as trash eaters, we think of rabbits as carrot-nibblers. So cute! But not everywhere is the rabbit considered so benign. In Australia, where rabbits nibble some $125 million worth a year of agricultural crops, there is a new rabbit czar, tasked with curbing the Australian bunny population. In her book, Bethany Brookshire writes about many other animals who are considered pests in some circumstances, even if they don’t deserve to be — like snakes and elephants and coyotes. And the well-known bird that some people today call “rats with wings.”

BROOKSHIRE: The pigeon became domesticated around 8,000 years ago we think, which makes it one of the earliest domesticated birds. Pigeons were cornerstones of many societies. They were incredibly important. Not just for food, though we absolutely ate them. If you’ve never had squab, I highly recommend. It’s delicious. We used them as messengers. And, in fact, we decorated pigeons that served in war. Pigeons were used to carry messages, and one of my favorite things is that pigeons were the foundation of modern journalism.

DUBNER: Sorry? 

BROOKSHIRE: Yeah. . 

DUBNER: How so? 

BROOKSHIRE: When the wire service Reuters started, it was not on a wire, it was on the wing. It was on the pigeon, because Reuters figured out he could fly hot stock tips to and from Aachen and beat the train by two hours. And, of course, we also use them for their poop because pigeon poop is excellent fertilizer. And there’s wonderful dovecotes — you can still see some of them today — developed by the ancient Persians that are these beautiful bell shapes so that all the poop falls to the bottom, and you can scoop it. 

DUBNER: Okay, so that history of pigeons is really interesting. But now — pigeons, they’re what, just another pest, essentially? 

BROOKSHIRE: Yeah, there’s a wonderful piece of work by Colin Jerolmack, who actually documented the fall of the pigeon in the public eye via articles in The New York Times over a century. And he was able to document that over about 100 years pigeons went from noble, innocent, beautiful to rats with wings. We no longer needed fertilizer. We have chemical fertilizer. We don’t need messengers anymore. We have email. And we don’t need squab anymore. We have chicken.

DUBNER: How would you say that the history of the human-pigeon relationship compares with the history of the rat-human relationship? 

BROOKSHIRE: I would say the history of the human-pigeon relationship differs in that we once had a use for the pigeon. I think of the pigeon as kind of the outdated cell phone of the animal world, right? We used to have such a use for them, and now we don’t, and we can’t fathom why they won’t go away. It’s so sad.

DUBNER: Okay. And if I were to ask you to summarize the downsides and the upsides of rats generally, how would you characterize that? 

BROOKSHIRE: Well, there are plenty of downsides associated with rats. People don’t like them. They find them both physically and psychologically really stressful. People who live very closely with rats, it’s awful. No one should have to live that way. Rats give people feelings of unsettledness, right? They are very associated with our feelings of disgust — and I’m saying that in terms of Western cultures, in terms of the global north. Other cultures do not associate rats with disgust. 

DUBNER: Give me an example of where rats are not thought of as disgusting.

BROOKSHIRE: So, the Temple of Karni Mata, it’s located in Deshnoke, India. This temple houses around 25,000 black rats, and those rats are considered sacred. They are holy. I got to speak to some of the people who, help run the temple, who cook the food for the rats. It’s a beautiful temple. It has solid silver doors carved with rats. There are beautiful marble floors for the rats. The rats drink from beautiful decorated bowls of milk — huge bowls of milk. They eat a wonderfully healthy diet. They get whole wheat bread, like whole bran. They get fruits, vegetables. And people come to make fire and food offerings to these rats. It’s because the rats are not considered to be real rats — the rats are reincarnations of people? So, the legend is that this woman, Karni Mata, grew up in that area, and she grew up to be a sage, she had mystical powers. And so when her sister’s son passed away — he drowned while playing — her sister brought her the boy and begged her to bring him back. And Karni Mata interceded with Yama, the God of death. And Yama said, “Okay, the people from your family will no longer die. They will be reincarnated as rats. And then those rats, when they die, will again be reincarnated as people.” And so, now, that temple — the family does still worship there, and it has been several hundred years. But other people, devotees, worship there as well because they believe that they will also be blessed if they are devoted enough to be reincarnated as these rats. 

DUBNER: What would you say are the drivers of the difference between one place or one culture and another, one in which the rat is looked at as just disgusting — a menace, dangerous, scary, etc. — and one where it’s not? What constitutes that difference, do you think? 

BROOKSHIRE: I would say there are a couple of things. There is one angle that’s very cultural, right? I ended up interviewing for my book a bunch of people who worked in biblical scholarship. We ended up talking about translations and our understandings of things like Genesis, “And God gave people dominion over the animals.” 

DUBNER: It’s a big line, yeah.

BROOKSHIRE: And that has become very deeply ingrained in many of our cultural ideas of what we should be able to control and how we should be able to control it. I would say that’s one of the reasons that we hate these animals, is because we expect animals around us to fail. We are prepared for that. We move into an area, we pave it over, we put up a Walmart, a Target, a Starbucks, a McDonald’s, what have you, and we expect the animals to leave. And then we wring our hands. We are so upset. We have killed off this beautiful species. This species becomes beautiful. It becomes charismatic. It becomes this wonderful thing. And look at the horrible stuff we’ve done to it. But when an animal is still there, we’re kind of mad. We don’t like it. It’s now where we’ve decided it doesn’t belong even if it always lived there. Now, it’s our space. You don’t belong there anymore. And we get really upset, especially if the animals begin to thrive, and especially if they thrive off things we value, right? Our gardens, our crops, our cats. We really hate them. We hate their success because their success feels like our failure. 

DUBNER: To the animals that we call pests, what are humans? Are we just, you know, pests that text and build parking lots? 

BROOKSHIRE: That’s actually something I got a lot when I was writing the book is: It’s humans — humans are the real pests, we’re the ones invading the world and taking it over and making it awful. I think that’s too easy. Because it’s the sort of thing that makes you fling up your hands and be like, “Oh, there’s nothing I can do.” We have choices in the way that we treat other animals, and we have choices in the way we treat each other. And we don’t need to live the way that we always have. 

GLAESER: So I think it is certainly true that the innate human reaction to rats — I don’t know why — is largely revulsion.

That, again, is the economist Ed Glaeser.

GLAESER: Certainly, when you see them in an urban context surrounded by trash, right? So you associate the rats with the filth, with drinking the water in the subway, right? It’s hard not to think of that as being sort of awful. 

DUBNER: Since rats are no longer a big disease vector, at least for now in most places, do you think our frightened view of them is simply outdated? And that for the most part, rats are — yes, a negative externality of humans in cities, but a really minor one that we shouldn’t worry so much about. 

GLAESER: I think it’s probably pretty small. That being said, I would still probably be in favor of policies that keep the rat population manageable, in the sense that who knows what happens if you let it get incredibly vast. Who knows what new diseases occur or what spreads across things. So I think some control but not making a fetish out of complete eradication. 

DUBNER: So, Ed, let’s play a quick game of word association. When I say “rats,” you say what? 

GLAESER: Cuddly. 

DUBNER: Come on, now. You’re just trying to make me happy now, aren’t you?

GLAESER: It’s hard not to think that rats have gotten something of a bad rap. They certainly are not healthy to have in vast numbers around you. But, you know, it’s a very urban species and I tend to like that. They sort of co-live with humans. They’re in some sense our natural city partner.

DUBNER: I want to run past you, Ed, a couple of titles we’re considering for this series. Let me know what you think. One is “The Exoneration of the Rat.” Too much?

GLAESER: It feels a little strong. It feels a little strong because it’s not like this thing does not do anything. But something in that neighborhood sounds good. 

DUBNER: Could I interest you in “Sympathy for the Rat”? 

GLAESER: Yes. Yes. I love it. I love it. And the echo, of course, with the Rolling Stones is great. 

DUBNER: Although the Rolling Stones’ sympathy — this is “Sympathy for the Devil” — the devil is the narrator of that song. You know, “I shouted out, ‘Who killed the Kennedys?’ When after all, it was you and me.” So it’s not the purest sympathy, let’s say. Do you still like this angle? 

GLAESER: I do. I do. I think in general, having sympathy for a creature that, you know, coexisted with us, that suffers many of the same negative sides from cities as we do, that enjoys many of the same positive sides of cities that we do, the ability to create this ecosystem, I think that’s a very worthy aim. And if we do have to control the rat, not viewing it with so much horror, but rather viewing it as being, you know, our urban partner, it seems like it makes more sense. 

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Freakonomics Radio is produced by Stitcher and Renbud Radio. This episode was produced by Zack Lapinski, with help from Dalvin Aboagye. Special thanks to Freakonomics Radio listener Jason Weeks for suggesting this topic. The Freakonomics Radio Network staff also includes Alina Kulman, Augusta Chapman, Eleanor Osborne, Ellen Frankman, Elsa Hernandez, Gabriel Roth, Greg Rippin, Jasmin Klinger, Jeremy Johnston, Jon Schnaars, Morgan Levey, Neal Carruth, Sarah Lilley, and Theo Jacobs. Our theme song is “Mr. Fortune,” by the Hitchhikers; our composer is Luis Guerra.