Neil deGrasse Tyson Is Still Starstruck

Hey there, it’s Stephen Dubner from Freakonomics Radio. And I’m busting into this People I (Mostly) Admire episode to tell you about two upcoming Freakonomics Radio live shows — in San Francisco on January 3rd and in Los Angeles on February 13th. For tickets, go to freakonomics.com/liveshows, one word. I’m told that tickets are going fast so, you might want to do this soon. Again, that’s freakonomics.com/liveshows. January 3^rd in San Francisco, February 13th in L.A. I’ll be there — and I hope you will too. Thanks.

*      *      *

My guest today, astrophysicist Neil deGrasse Tyson, has probably done more to popularize science than anyone else currently alive. Following in the footsteps of Carl Sagan, he hosted the reboot of PBS’s series Cosmos, and he’s written nearly 20 popular books. But perhaps what he’s best known for is his weekly program, StarTalk, which has accumulated nearly 600 million views on YouTube. He’s also active on the X platform, formerly known as Twitter, where his thoughtful and sometimes provocative tweets have earned him 14.5 million followers.

TYSON: I said “Students who get straight A’s do so not because of good teachers, but in spite of bad teachers.” That’s just a fact. You can’t bring your straight A student to me and take credit for it. Why do they get straight A’s? Because you didn’t matter. You had crappy teachers in your school and they got straight A’s in that class too.

Welcome to People I (Mostly) Admire, with Steve Levitt.

What you probably do not know about Neal is that it’s kind of his fault that Pluto was demoted from planetary status. That’s where we begin our conversation.

*      *      *

TYSON: Yeah, no, I was an accessory to the demotion; never carried a weapon in this, but I definitely drove the getaway car. We’re going back a few years now and apparently you still haven’t overcome this planetary tragedy, others have moved on. I don’t know if you understand this, but as more and more data was accumulated over what Pluto is, what it’s made of, what its orbit does, how small it is, what its mass is, it just could not hold up its bargain with being the ninth planet. And in 2006, an official vote was taken of the International Astronomical Union. It’s just the group of international astrophysicists, which has a nomenclature committee to adjudicate this sort of thing. And they officially sent Pluto from a planet status to a dwarf-planet status. And I think Pluto’s happier there actually. It’s now one of the biggest of the dwarf planets rather than the puniest of the red blooded planets.

LEVITT: The fact that we discovered Pluto in 1930 was kind of lucky and an accident, right?

TYSON: Let’s go back in time. William Herschel accidentally discovers a planet orbiting beyond Saturn — Uranus. No known human being had ever discovered a planet before.

LEVITT: This is what — the 1600s or the 1700s?

TYSON: Herschel’s operating in the 1700s. This is way after Copernicus, which is in the middle 1500s, where he said, “Hey, wait a minute, maybe Earth is actually a planet, orbiting the Sun, and the Sun is in the middle.” So the definition of planet had to be adjusted to then include Earth and remove the Sun and the Moon. There are seven classical planets: Mercury, Venus, Mars, Jupiter, Saturn, the sun, and the moon. These seven objects are the only objects known, at the time, to move against the background sky.

LEVITT: They’re all easy to see.

TYSON: Exactly. Cavemen knew about these. By the way, the seven days of the week, the names that we give them, derive from these seven classical planets: Mercury, Venus, Mars, Jupiter, Saturn, the Sun, and the Moon. So Sunday is named for what?

LEVITT: I think probably the sun.

TYSON: Yes, very good. Okay. Saturday?

LEVITT: The moon?

TYSON: No, Saturn! Saturn! These are not hard questions! These are not hard questions. Okay, here’s another easy one: Monday.

LEVITT: Monday’s the moon.

TYSON: Moon! Good. There you go. So, Herschel comes around. And he accidentally discovers an object. He doesn’t even think it’s a planet, because no one’s discovered a planet before. Why would anyone think a planet was a discoverable thing? All the known ones are known. So, he thinks it’s a comet. And he publishes a paper on the account of an unusual comet. And he says, “Odd comet. It doesn’t show much fuzz. I’ll keep watching it. Oh, it continues to not show fuzz. What an unusual comet this is.” This is how your prior biases can prevent what might be a discovery. But finally, he realizes, “Oh my gosh, we’ve discovered a planet,” and he wanted to — this is the late 1700s — he wanted to name it after one of his principal benefactors, King George. That’s the same King George of the American Revolution. So for about 30 years, there are textbooks — I own one of them — that enumerated the planets, “Mercury, Venus, Earth, Mars, Jupiter, Saturn, and George.” Fortunately, clearer heads would prevail. The planets have Roman names. Those are Roman gods — Saturn, Jupiter. As an homage to the Greek mythologies, the moons of the planets are named for assorted characters in the life of the Greek counterpart to the Roman God after whom the planet is named. For example, one of Jupiter’s moons is Ganymede. Ganymede was the manservant to Zeus and Zeus is the Greek counterpart to Jupiter. So that’s how that worked out. Until Uranus. If we take away King George’s name, we got to give something back because you don’t want to piss off the Brits — especially at that time, the world’s most powerful army and Navy. So moons of Uranus, they’re named for fictional characters in Shakespearean literature. You have Puck and Oberon and Miranda. These are all characters from A Midsummer Night’s Dream and The Tempest. Anyhow, we’ll get back to Pluto very quickly here. We look at the orbit of Uranus and we find out it’s not exactly following Newton’s laws, which were well established by then. So people were saying, “Oh my gosh, maybe we found the outer limits of the applicability of Newton’s laws.”

LEVITT: So maybe Newton’s laws are not universal.

TYSON: Maybe they’re just Earth and the moon. Maybe just a solar system thing. Perfectly sensible thought. And someone else said, “Maybe it’s not. Maybe there’s another force of gravity out there that we have yet to reckon in our tables tugging on this, giving the illusion that it’s disobeying Newton’s laws. So let’s find out if, in fact, there is another object out there.” But it required extreme mathematics that was very difficult. Where would a source of gravity have to be and how strong would it have to be to influence the movement of Uranus in the way we observe?

LEVITT: Made more complicated because all the planets are moving too. So it’s a dynamic problem.

TYSON: All of the above. So it needed some of the world’s best mathematicians, Le Verrier among them, a French mathematician. He did the math, calculated if Newton is still correct, there’s a planet over here in this part of the sky. He got this information to Johann Galle, who is an astronomer at the Berlin Observatory. That night he discovers Neptune.

LEVITT: That’s awesome.

TYSON: A triumph of Newton’s laws, a triumph of mathematics, a triumph of our understanding of the universe, a beautiful fact. So that would be like nearly a hundred years later in the 1800s — another planet is discovered. So now we up the number of planets. Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune. We’re up to eight! Now we start looking at Neptune’s orbit. It’s not quite following Newton’s laws. Well, we’ve been down that road before. We know what we’re doing. There’s got to be another planet out there: Planet X. So we did the math. We said, “Look there!” Nothing there. Okay, maybe we didn’t do the math right. “Okay, look over there!” Nothing there. Nobody found anything for a hundred years. And then Percival Lowell, he figured out that clouds are bad for looking at the universe. So he built an observatory on a mountaintop in the desert, Arizona. He says, “I know what I’ll do. I’ll systematically search for Planet X.” If you expect them to be in the plane of the solar system, you can take big photos in that and compare them with previous photos you’ve taken. And you just do this systematically across what’s called the ecliptic. He dies before the discovery is made, but Clyde Tombaugh, a devoted amateur astronomer, conducts this search. And he makes the discovery. Planet X is discovered.

LEVITT: Back in the ’30s.

TYSON: Correct. If you read The New York Times reporting on science published regarding Pluto, they give it a mass. We didn’t measure this mass. This is the mass it would need to have to perturb Neptune in the way we see Neptune’s motions being perturbed.

LEVITT: Wait, can I ask you a question about that? The first time around, they knew where to look.

TYSON: The second time around they knew where to look, but it wasn’t there.

LEVITT: Yeah, that’s what I’m saying. Wouldn’t it be a problem if you give it the mass of the thing, but it’s not in the right place?

TYSON: Yes. You’re being rational here and not emotional. Let’s get back to the emotions. “Oh my gosh! This amateur astronomer discovers Planet X! And let’s celebrate and let’s have articles and parades!” But as we get more and more actual data on Pluto, the size was really small. Smaller than anybody had ever presumed. And by the way, we continue to look at Neptune’s orbit and we discover that, no, Pluto cannot be the culprit here. Planet X is still out there. So the search continued, but Pluto sneaks into the textbooks as the ninth planet, and elementary school children memorize the nine planets. So what happens, early ‘90s? There’s a paper published by Myles Standish, worked for the Jet Propulsion Laboratory. He analyzed the datasets that contributed to the orbit of Neptune — the orbit that we calculated for it. And he noted that certain data obtained from the U.S. naval observatory, looked a little anomalous. Observatory logs are very detailed, because you don’t know what could be a force operating on your observations. Everyone who comes in, did you touch anything? Did you breathe on anything? Everything is noted. So he said, “All right, I don’t trust these observations.” They meddled with the gear system and the gear system can affect the pointing of the telescope and affect the coordinate you would then write down for where the object is in the sky. He removed the data from the U.S. naval observatory, ‘cause you’re using data from all around the world, and refit the curve and it fits exactly onto Newton’s Law.

LEVITT: So we never should have been looking for Planet X.

TYSON: Pluto was never planet X, ever. It’s just another object out there. And in the 1990s, we discovered similar objects to Pluto orbiting in a similar orbit. There are objects rivaling Pluto in size out there, with Pluto’s cockamamie orbit. In fact, collectively we call them Plutinos, the family of objects that share Pluto’s orbital properties.

LEVITT: So you’re saying already by the ’90s, Pluto is on the outs—

TYSON: Pluto was never a full red blooded planet. It’s not like, “Oh, we were all agreeing this belonged there. And then we just all not agree.” It always had issues. 

LEVITT: So you can say that now, but you wrote in your Merlin column that you wanted Pluto to be a planet. You’re changing your tune it sounds like.

TYSON: Oh, no, Merlin. Merlin said that.

LEVITT: So Merlin is your alter ego.

TYSON: Yeah, I wrote a column in the mid-1980s, continuing into the early 1990s, with Merlin as the pen name. And people would write in and ask questions. This Merlin is an alien, born in Andromeda — visits Earth, studies Earth civilization, and has known all the greatest people who made discoveries. So if you ask Merlin, ‘cause it’s a Q&A column, “I don’t quite understand gravity. How does that work?” Then Merlin would recall a conversation with Isaac Newton and Isaac Newton would then give the answer. That original column was made into a book that came out in 1989, and Merlin took the pop culture side of that argument saying, “Well, it’s been a planet for 50 years. Merlin’s happy just keeping it that way.” That’s an untenable position in the 21st century update of that book.

LEVITT: So, Pluto. We had gotten up to the point where everybody maybe felt like it shouldn’t be a planet, but nobody was doing anything about it. 

TYSON: In the year 2000, we opened the newly renovated, rebuilt Hayden Planetarium, where I now serve as director, and we wanted to future-proof the exhibits. So in the section where we talked about the planets, we removed Pluto and put it in the section where we talk about comets and asteroids. And this got noticed by The New York Times, and had a page-one headline, “Pluto not a planet? Only in New York.” And then all hell broke loose. So that’s when I started getting hate mail from third graders.

LEVITT: You opened in 2000. This article came out in 2001. It’s very telling about how the media works that something can be unnoticed for a year and yet be a firestorm, front page headlines. Everybody goes crazy.

TYSON: The headline itself was inflammatory. It was definitely, “Oh, Neil is an outlier.” And then the International Astronomical Union votes exactly how we had planned it.

LEVITT: Since when is science done by a vote? Imagine if they voted on whether Darwin’s theory was right or Copernicus’s theory was right? Number one, they would have voted the wrong way —

TYSON: We’re not voting on what science is true or not. We’re voting on nomenclature. You can’t really communicate unless everyone knows what the nomenclature is. If you discover a comet, what are the rules for naming a comet so that there’s consistency? What are the units of measure we should use when we’re talking about this phenomenon in the universe versus that? And so the question was given that the word “planet” was never formally defined since ancient times. In fact, the last time it was defined unambiguously was when “planet” — from the Greek planétés, meaning wanderer — when we had the seven wanderers, the sun, the moon, Mercury, Venus, Mars, Jupiter, and Saturn. That’s the last time it was defined unambiguously. So they created categories of planets. If I say “dwarf planet,” you will know the object is large enough to be spherical, because gravity makes that happen, but not so large that it owns its band around the sun. There are thousands of other objects orbiting the solar system at Pluto’s distance. It does not command a space the way what we’re calling planets do. Henceforth, Pluto’s a dwarf planet. There’s an asteroid called Ceres, which was big enough to be a sphere. That got promoted from being an asteroid to a dwarf planet. Now, if you want to just call everything that orbits a star a planet, I don’t have a problem with that. It just renders the word completely useless. After you say, “I discovered a planet orbiting a star,” then we have to play 20 questions before I even know what kind of object you’re talking about.

LEVITT: There is still one place in the world where Pluto is a legitimate planet. And I don’t really understand why, but it’s New Mexico.

TYSON: New Mexico is the home of Clyde Tombaugh.

LEVITT: Okay, so even though the observatory was in Arizona, the guy who discovered it was Clyde Tombaugh, and he lived in New Mexico. Now, the other place that Pluto is a planet — was it Voyager that we sent into outer space with the—

TYSON: Yeah, there’s a plaque, the plaque that went on four spacecraft. Each of them had enough energy to escape the solar system. So it was Pioneer 10 and 11, followed by Voyager 1 and 2. And these spacecraft, because they had enough energy to leave the solar system, were affixed with a plaque that could be read a billion years into the future by any alien civilization that might stumble upon the contents of those images. So it gives the direction to all the pulsars. It has a return address, which seemed like a good idea at the time. Today, you wouldn’t give your email address to a stranger of your own species, much less an alien of another planet.

LEVITT: Do you think the directions we gave on those plaques — first of all, we gave the wrong directions with Pluto, but would anybody actually be able to find us based on that?

TYSON: On the plaque, it had this representation of the sun and the nine planets, and the third planet out is displaced towards the spacecraft, so that any person reading this would have some understanding. Pluto is represented in these little circles that are in sequence away from the sun: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune, and Pluto. So I joked that aliens who pick up our return address stumble on this plaque, come into our sector of the galaxy, start looking for us — they won’t find us, because they’ll find only eight planets, And they’re looking for a solar system with nine planets.

LEVITT: I once heard you say something really interesting that stuck with me. We haven’t even figured out how to talk to a single species on our own planet. Why do we think if aliens showed up, we would have no trouble at all understanding what they’re saying?” I’ve never heard anyone else say that, but it makes sense.

TYSON: Chimps are intelligent by many measures, yet they can’t talk to us. We can’t even talk to them. So bring in some aliens that have that same gap between us as we and chimps have, and nobody’s talking to anybody.

After this short break, I’m back with Neil deGrasse Tyson.

TYSON: What are you basing that on?

LEVITT: On your autobiography.

TYSON: No.

That’s after the break.

*      *      *

LEVITT: You are the director of the Hayden Planetarium in New York City. It is almost like a made for TV movie, right? Because you write about as a kid growing up in New York, the Hayden Planetarium changes your life. And then it’s amazing you end up running the place.

TYSON: Yeah, my parents took my brother, sister, and me all around the city every weekend, go to an art museum or the aquarium — we’d go to athletic events, the opera, as kids. And, you know, I slept through a lot of things, but it was still an exposure. It was kind of a baptism into the world of what adults do. And one of the trips was to the Hayden Planetarium and I was starstruck. I’ve not been the same since.

LEVITT: Because growing up in New York City, you don’t really get to see much in the sky.

TYSON: Let me say that more strongly. We don’t have any kind of relationship with the sky at all. When you look up, you see — back then it was smog and buildings and street lights. The sky doesn’t mean anything to you. Then I go into the dome and they dim the lights and the stars come out. And I said, “What is this?” In fact, I thought it was a hoax. “I’ve seen the night sky from the Bronx. I’ve seen all eight stars in it, and this is all a lie.” By the time I was 11, that’s when I had an answer to that annoying question that adults always ask kids.

LEVITT: What do you want to be when you grow up?

TYSON: It was “astrophysicist.” And that pretty much ended the conversations right there. Well, if you say, “I want to be a lawyer,” “Oh, Aunt Matilda’s a lawyer. Uncle Joe’s a—” Nobody knew anybody who was an astrophysicist. So it was a pretty fast conversation.

LEVITT: But you weren’t really a very good student at that time, right?

TYSON: What are you basing that on?

LEVITT: On your autobiography.

TYSON: No.

LEVITT: I thought you said that in fifth and sixth grade you weren’t that good a student, and it was only later that you became a good student?

TYSON: Oh, no, no. I was an average student in the eyes of the school. To say I wasn’t a good student implies that I’m flunking out. No, no, I got average grades. I got A’s, B’s, and C’s. If you poll the most significant influential people in life, even throughout civilization, and ask, “Were you a straight A student?” The answer is going to be no in 99 percent of those cases. That’s my first comment. Second, I was always committed to learning. Always. I had a library at home larger than most kids. My parents would buy the cheap books from the remainder table — they knew I was interested in the universe since age nine. They find a math book, a physics book, and they just get it for 25 cents. And so I had all these books. Then, in middle school, I walked dogs. I lived in a big old apartment complex and nobody wanted to walk their dogs. And so I used that money to buy my first telescope. I bought a camera. Converted an interior bathroom into a dark room. Meanwhile, I’m getting average grades. And I was always passing notes and always whispering. So if you look at my report cards — one day I will publish them — the teachers are saying, “Less social involvement and more academic diligence is in order.”

LEVITT: One of the tweets you had that really stuck with me — you wrote, “Some educators who are quick to say, ‘This student doesn’t want to learn,’ should instead say to themselves, ‘Maybe I suck at my job.'” I love that tweet! I mean, it’s what you’re saying now, but much more bluntly. And I think there’s so much truth to it, but nobody ever says stuff like that.

TYSON: All I’m saying is my B average — none of my teachers in elementary school, middle school, high school, college, graduate school would have ever said, “Watch him. He’ll go far.” Meanwhile, like I said, I am all in, in physics and astronomy and the universe and science. I went on an expedition at age 14 alone, not with my family, on a ship to the Northwest coast of Africa to observe a total solar eclipse with my telescope, and one of the longest eclipses in the millennium. Then I did research in England, at Stonehenge and other related monuments, which imprinted in me to the fact that, to this day, I take the sunset on the grid of Manhattan, and I coined it Manhattanhenge. That word is now in the Oxford English dictionary.

LEVITT: Because there’s two days a year where the sun lines up with the East- West streets in Manhattan?

TYSON: With the East-West grid of the Manhattan streets. And it makes for striking sunset, framed by the steel and glass skyscrapers. Tens of thousands of people flood the streets now for it. My point is, everything that I was, was not entirely measured by exams in school. Teachers don’t see any of that. They don’t even care about it. They just care that you’re obedient. You don’t tell jokes. You do the homework and you get high grades. I was interviewed by The New Yorker for one of their profiles. And when I said, “I had a B average,” that showed up in the article that: “In school, Neil was a mediocre student.” I was going to write a whole article on that New Yorker article that was fact checked, but not impression checked. If the impression isn’t accurate, it doesn’t matter that the fact is correct. You’re not communicating meaning accurately.

LEVITT: You know what I find interesting about that is you are a scientist through and through, right?

TYSON: Bones, all the way in.

LEVITT: But at the same time, you’re also a humanist. Because no scientist talks about impressions. And somehow you managed to transcend data and put that together with emotion in a very interesting way. I think that’s your secret sauce. What do you think?

TYSON: Well, it could be. That’s just, I think, socialization? My parents were social animals. They had dinner parties a couple of times a month. I had exposure to what it was to entertain, to interact with people, to conduct and hold, sustain, end, begin a conversation. So I would say that as an educator, if I just face the chalkboard and talk, then you have to meet me 90 percent of the way there. Well, if that’s what I’m doing, then I’m a lecturer. But if I turn around, face you and meet you 90 percent of the way to where you are, then I’m an educator. And doing so means I have to think about, what are you thinking about? What are your receptors for learning? What is your capacity to retain information? How can I influence that? What words do I use? How long should my sentences be? Should there be an infusion of humor so that you’ll smile while you’re learning, you associate good feelings with the new thoughts, and you come back for more? This is what I have honed over all these years. By the way, a lot of the tap roots of that landed in my very first book, Merlin’s Tour of the Universe. In there are rhymes and poetry and sentence structure that is intended to draw you in, to get you to want more, to make you smile, to make you laugh. So, I don’t mind calling it a secret sauce, but I don’t want it to be a secret.

LEVITT: It’s your sauce. It’s just not a secret. It’s easy to talk with you only about cosmology, but I do think you’re a very astute observer of society. And I think that comes through most clearly in your book, Starry Messenger. And one of the things you write about I found really interesting is that you are liberal on many things, yet you spent time on commissions in the George W. Bush administration. Could you talk about that a little bit?

TYSON: So I wouldn’t say I’m liberal “yet” I spent time on two Bush-appointed commissions. I would say I’m liberal “and” I spent time on those two commissions. “Yet” implies a contrast of outlook. The White House called me within a month of when he was inaugurated and asked whether I’d be interested in serving on a commission. It was a little bit initially awkward because during the questioning they did of me on this phone call, they asked every question that would otherwise be illegal in a job application. Because it’s not a job. So they can ask you anything. “Are you or have you ever been a member of—? Did you ever protest? Are you religious? What newspapers do you read?” So I get through all of that. And they said, “Are you familiar with the president’s policies? What do you think of them?” And I wanted to like reach through the phone and grab their lapel and said, “How did he get elected? What the hell happened? By the way, they’re still counting dimpled chads in Florida. How come he can’t pronounce the word nuclear? He’s got his finger on the button! It’s not nuc-u-lar, it’s nuclear!” All right? And then I thought that would not be productive. And I saw who he had been appointing — Colin Powell, can’t argue with the pedigree of Colin Powell. Condoleezza Rice, provost at Stanford. And I said, “Well, whether or not he’s the sharpest knife in the drawer, he’s hiring people who are sharp knives. These are good people.” So I summoned within me — in response to the question, “What do I think of his policies?” I said, “I applaud the president’s efforts to surround himself with talented people so that he can make the best decisions he can in the interests of this nation.” Then I was appointed. By the way, in the Q&A, it says, “Are you registered to a political party? Who’d you vote for in the last—?” It was all of that. So they knew I didn’t vote for him. They didn’t care. They were after my expertise and my perspectives and my wisdom. My friends, very liberal leaning friends, find out that I’m going to work in Washington for George W. Bush. Their first thought was, “Oh, he must have needed a Black person on the committee.” They would not allow the possibility in their head that that president, a Republican, would have any reason other than some nefarious political strategic thing, rather than maybe he just wants to get the best committee that he can assembled. So I got to see intelligent Republicans, ones who are thoughtful. They just come from a different place than you do, so their valuation of what matters to them differs, which can be odd if you’re very far left. In the same way, very far left people look odd to people on the very far right of the spectrum. And many pages are devoted, in Starry Messenger, trying to unpack the belief systems that were behind the division that was so strong in the country.

LEVITT: The election has just happened, the presidential election, and I think you and I might have this in common that I’m almost a single issue voter. And what my issue is, is: do the candidates think sensibly and like scientists? I can put up with left or right if I feel — it’s very much like what you said about George W. Bush, but if the people in the administration are thoughtful, good people who think reasonably and tackle problems using data, I can kind of tolerate anything.

TYSON: You wish there was a third ticket called the Rationality Ticket. And whoever’s there, no matter their political leanings, that’s what you’d be in for.

LEVITT: I don’t like the word “rationality” because it’s been so tainted within economics. What rationality has come to mean in economics is a heartless, emotionless calculation that often leads to absurd conclusions that are very much at odds with the way society works. So rational, in an economic sense, is an extreme. There’s no room for anything else. And I’m opposed with that.

TYSON: I am fascinated to learn this. If trying to get the best results using what you might call rational thought does not get the best results, then redefine what is rational so that it always gives you the best results. My issue with economics — if I may, in this space, deliver this — is the fact that there’s such a thing as a conservative economist or a liberal economist means you should not put the word “science” on the category — “economic sciences.” No! Remove the word. You haven’t earned it. There’s no such thing as a conservative physicist. They’re physicists who will vote conservative, but there’s nowhere in their work that means he’s voting for Tru— no! I don’t want to be an a****** about it, and without the word “science,” then I won’t hold you to it! What swayed people a little bit is in the 1960s, someone said, “You know, there ought to be a Nobel prize for economics. Let’s make one and let’s give the award exactly the amount as the real Nobel prizes. And we can’t call it a Nobel prize because it wasn’t in his will. So we have to call it a prize in honor of Alfred Nobel.” The economics prize in honor of Alfred Nobel. Did I just piss off half of your listeners?

LEVITT: No, I hope that my listeners aren’t confused about what economics is.

TYSON: By the way, I don’t mind it. I love that about it! I’m praising it for how complex it is, and I’m not envious of how hard it is to try to understand human behavior that is fickle and will change just by whether a cloud came in front of the sun. I’m just saying science has a certain deterministic features to it — or precisely probabilistic, even if it’s not deterministic. The day that economics reaches that, go right ahead. Call it the Department of Economic Sciences. Until then, it’s just the Economics Department.

LEVITT: Honestly, in my entire life, I’ve not used the word science in combination with economics. You say social sciences —

TYSON: By the way, it’s sociology. Again, the attempt to boost it a few notches. My father studied sociology. That’s a perfectly fine word. That captures everything you mean when you say “social sciences.”

LEVITT: Let me tell you about the economic method of doing research, which I will contrast with the scientific method. So in general, what economists do, consistent with the scientific method, is that they come up with a hypothesis and then they go and get a bunch of data. And I got to say, my entire life, I’ve almost never had the data I collected match the theoretical hypothesis I put forth. Now, obviously, in the scientific method, you go and reformulate your hypothesis and then you maybe gather more data. What you do in economics is you say, “Oh, well that was inconvenient. So in my theory section of my paper, let me go and backwards engineer the theory that is consistent with the data I collected.” They write a theory that matches the empirical data without ever acknowledging the fact that it wasn’t the theory they started with. What we should do, and what I eventually in my career started doing, is saying, “Look, I just went and gathered a bunch of data. Here’s the data I collected. And there are four possible theories I can think of that might be true. Three of them match this part of the data. Two match this part of the data. I’m going to go get some more data now that I’ve understood the theories.” And it’s not the scientific method; it’s a sensible method for how, in a data-driven world, you try to figure out what’s going on. What to me is so disturbing about economics is that everybody knows it’s completely fake, what we do. And no one talks about it, and everybody pretends they’re following the scientific method, when in fact we’re doing nothing like it.

TYSON: I think you’re being too hard on yourself. Let me, first, tighten up some of your vocabulary. If you have an idea about how something works, it’s not a theory; it’s a hypothesis. A theory in science is an understanding of how things work that not only explains all that it has confronted, but makes predictions that have been shown to be accurate going forward. That’s a theory. That’s where we get the theory of relativity, quantum theory, evolutionary theory, Big Bang Theory — oh, that’s the TV show. Until then, until you have experimental verification, you have a hypothesis. So you put forth a hypothesis, some of the data don’t quite fit it and you go back and readjust the hypothesis. That’s just fine. You readjust the hypothesis and now it fits the data. I don’t have a problem with that. But don’t elevate it to a theory of human behavior until that hypothesis makes a prediction you then test. I don’t care what you do with your hypothesis. I don’t care how much stitchery and re-mending you have to do to it. Once you present it, and it accounts for the data you have available, that is the beginning. That’s not the end. Now let’s test it. Can you make a prediction? Then we’re onto something. If after you’ve retooled it it makes more predictions than you ever imagined, bada bing, let’s call it a new economic theory.

You’re listening to People I (Mostly) Admire with Steve Levitt and his conversation with Neil deGrasse Tyson. After this break, Neil talks about what it was like to interview Stephen Hawking.

*      *      *

Very few people enter grad school with the idea that they’ll be popularizers. I’m guessing that when Neil deGrasse Tyson started his Ph.D., he was dreaming of making big discoveries, hoping to win a Nobel Prize. So I’m curious whether it was hard for him to make the transition to being a popularizer, especially when all the forces within academia are telling young people that academic papers and original research are all that matter.

TYSON: Carl Sagan, he was the first through the brush and the bramble, and there’s blood on the tracks because of it. When he first appeared on The Tonight Show with Johnny Carson, oh my gosh, his colleagues would say, “What’s wrong with you? You realize that’s not a news show, that’s a comedic talk show, and that’s no place for a sci—.” So he bore most of the brunt of that resistance. By the time I came along, its value to the field was very well known because if Congress is ready to vote on some new telescope, and the member of Congress said, “Wait a minute, didn’t I see Carl Sagan talk about that on TV? Or didn’t I see Tyson? I like that! That’s a good thing.” And it can influence funding. When my field realized this, they turned a much more charitable eye to activities engaged in that way.

LEVITT: I have to say, the products that you put out, whether it’s the various versions of StarTalk, the Cosmos TV show, the books you write — it’s no wonder you have a huge audience. You manage to put humor and joy into everything you do. And I think maybe what I might call it is: you make science friendly. There are different kinds of popularizers of science. Like I’ve spent a lot of time recently with Richard Dawkins. And he and you, I think, are polar opposites because Richard represents the draconian view of science. Like, “Science is correct. You can only think scientifically. If you don’t, you are an idiot.” There is no tolerance. But when I watch or listen to StarTalk, it’s more like, “Hey, science is part of life. It’s okay to talk scientifically about Hollywood movies, and if they get the science totally wrong, it’s not the end of the world!” It’s like, “Oh, that’s kind of neat — this director got it right, this got it wrong.” You’re one of the few people who’ve succeeded in making science friendly and fun.

TYSON: Thank you. I like the word friendly as you used it there, because if one just says “the science is fun,” then okay, but when the fun is over, then you go home. Friendly, then you make it a friend and you’re no longer frightened by it or intimidated by it. And then you seek it out, almost as an old friend. Science is in our everyday lives. It does touch everything. This is not a charade. It is real. And yes, I think the humor component as well as the pop culture component, those are two legs on a three-leg stool — the humor, the science, and the pop culture — which when blended make for, I think, compelling learning. That’s the recipe DNA for my podcast StarTalk. 

LEVITT: Can we talk about my favorite StarTalk episode?

TYSON: You got a favorite? Go for it!

LEVITT: It’s the one with Stephen Hawking. And it must have been 2018 — right before he died actually, before he died.

TYSON: Yes, one of the last interviews before he died.

LEVITT: Partly what I find so impressive about that episode is you had to interview Stephen Hawking, and as someone who does interviews, I start to quiver with fear at what it must be like to interview Stephen Hawking. I mean, the intimidation of him having been so brilliant, but also it must take forever after you ask a question for him to twitch his cheek, to make the sounds. I mean, what is it like to interview Stephen Hawking? Just for starters.

TYSON: The interview is not efficient, but I think he mastered the art of simple communication containing maximal wisdom in the fewest number of words.

LEVITT: So just to paint the picture, the show starts with you talking a little bit, but then you cut to his office and you’ve got, like, your most serious tone and face on and you say, “Let’s start with the first question, the most pressing question of them all. What’s your favorite food? Mine is pizza.” And he says, “Oysters.” And the whole thing is so absurd because here’s the greatest physicist of our time probably, and here’s you, and nobody else in the world would walk into that guy’s office and ask him that question. It is pure entertainment. But then, a minute later, you ask him what his favorite equation is. And he gives some completely inscrutable answer about — was it S equals A over 4? Something equals A over 4.

TYSON: Yeah, it might have been the entropy of a black hole.  

LEVITT: The point though is, to me, that means nothing. But what’s so great about StarTalk is then you go back to the live studio audience and you explain what that means and I understand. I feel like an insider. I feel like I’m part of the science team and you’ve made sense of it. And then you ask him another question I think that only you would ask him, which was, “If you could go back and talk with Isaac Newton, what would you ask him?” And again, he gives an answer, which is completely and totally inscrutable. I don’t even know what he’s talking about. And what’s so cool is, again, you go back to the studio and then you explain why that is such an incredibly interesting answer. And again, like, “My God, I understand.”

 TYSON: Well, those feelings are what bring you back for more.

LEVITT: Exactly! It’s what makes me think, ‘Maybe I could go read A Brief History of Time. And maybe if Neil were sitting next to me, I’d actually understand A Brief History of Time.’ But the last part that I remember about this show that’s so interesting is you ask him some other question, and again, he gives some completely inscrutable answer, and you are nodding your head, and then you come back to the studio audience and say, “I didn’t understand more than 20 percent of what he just said.” And that again is something that is so good for an educator to be willing to do. Everyone’s so busy pretending they understand stuff they don’t understand, but for you, to millions of people, to say, “I had no idea what he’s talking about either,” that is as important as anything you’ve ever said, I think.

TYSON: Well, it creates a resonance with viewers. Thanks for noticing all that. Some of it is a direct probe of pop culture, which brings people in. You know, what is pop culture, but the common foundation of knowledge that we all bring to the table? And if I can use that pop culture as a scaffold and clad the scaffold with scientific bits and pieces and insight, then you will remember the science that much more.

I’ve been thinking a lot lately. I’ve been thinking a lot lately about how best to teach subjects like math and science. And I have to say, the more I watch programs like StarTalk and the more I read science books written for popular audiences, the more convinced I become that our heavy reliance on textbooks and memorization is a huge mistake. I’ve come to believe that our main goal should simply be to inspire people to want to learn more about a subject, to make science interesting. If you have an hour, if you have an hour to spare, I encourage you to watch the StarTalk episode featuring Stephen Hawking and ask yourself as you watch it, is this a better or worse way to teach people science than the textbook based learning we rely on in high school? And I’d be curious to hear your honest answer. Do you agree with me or do you think we should stick with textbooks? I’d love to hear your thoughts. Our email address is PIMA@freakonomics.com. That’s P-I-M-A@Freakonomics.com. Drop us a message and let us know what you’re thinking.

LEVITT: Now’s the time in the show… 

LEVEY: Hi, Levitt. A listener named Ashley sent us a question about human breast milk. Ashley works for a nonprofit human milk bank, which mainly supplies neonatal intensive care units or NICUs with breastmilk. Human milk banks get their donations from women who have excess supply. But they’re now competing with for-profit companies, which will buy breast milk from women for about a dollar per ounce. These for profit companies use breast milk to make fortifiers, or supplements for breast milk. Ashley, who works for a nonprofit, is understandably against paying women for breast milk, and she’s unsure how nonprofits are supposed to compete. She also wants to know your opinion. My guess, though, is that you’re going to be ecstatic that women can get paid for their breast milk. 

LEVITT: I absolutely am heartened by the fact that unlike with organs where we put all sorts of bans on it, there sensibly is not a ban on transacting for breast milk. I actually was the beneficiary of donated breast milk. My wife had low supply and so with one of our children, someone who was in a Facebook group with her who had excess supply just out of kindness would give frozen breast milk to families. And so we got a big batch of that from her. Though, I have to say the whole time that we used it, I lived in a deep terror that it was contaminated because it wasn’t pasteurized, and that we were doing real harm to our child. So despite her generosity, she would have given us much more. We decided formula was a better bet for us.

LEVEY: I should say here that it is recommended that if women do have excess milk supply that they donate it to a non profit human milk bank and then if people are in need of breast milk they can go to a milk bank instead of doing the more informal transaction.

LEVITT: Makes total sense. but in a world with a well functioning market where you had pasteurized breast milk, I’m an economist. I think that would be a good world. I think we should have that. Now, the question of whether breast milk should be distributed through the for-profit or the non-profit sector, to me, isn’t actually the right question. I think the right question is, what’s the highest value use of this excess breast milk, and how do you get it to those people? And I think right now, it sounds like the non-profit sector is trying to use breast milk in one way, and the for-profit sector is sending it in a different direction to make fortifiers. So in the end, really, it’s a social question: What’s the greatest value on this milk? And you might think if the greatest value is getting the milk to the neonatal intensive care unit, why are the for profit companies not doing that? Why are the NICUs not willing to pay for the milk? So it sounds like there’s some market failures going on here, and then I think the blame doesn’t go to the for-profit companies. It goes to the hospitals.

LEVEY: So one of the critiques of paying women for breast milk is that women will start selling their breast milk instead of giving it to their babies that actually need their breast milk. What do you think of that critique?

LEVITT: It hadn’t really entered my mind in this discussion so far. Although, of course, it makes total sense. Would it be bad if women did that? In some sense to an economist, no, we allow mothers to make an infinite set of choices about their children’s well being. I’m not sure why we would draw the line here and say that the woman who already could be giving formula to her child if she wanted could somehow by law or regulation be told you’re not allowed to make that choice for yourself. So I’m at ease with that. I could see how others would be bothered, but it’s a really fascinating moral question. It might be worth thinking about the magnitude of the dollars we’re talking about here, ’cause it’s not huge. I think a woman with big supply might have 50 ounces a day, and at the current price of a dollar a day, $50 a day, so $350 a week. It’s certainly not nothing. Of course, formula’s not cheap either. That really does raise an interesting question, but I would say because we let parents do pretty much whatever they want to their kids, unless it’s really outrageous, I have a hard time seeing how this would be the exact place the government would want to step in and say, “No, no, no, women aren’t allowed to choose whether to give their babies formula or breast milk.” If it means you’re going to give the breast milk to a child in the NICU who might not live without it.

LEVEY: Well, no, it would be selling it to the for-profit companies.

LEVITT: I know, but I’ve already moved on to the world that I’ve laid out where the best use of the breast milk is in the NICU. And so very quickly the hospitals are going to be forced by law or public approbation to be providing the breast milk to the children there, and so that the for profits will quickly swoop in and steal that market.

LEVEY: Ok, great. Glad we’ve moved on to your version of the world. Listeners, if you have a question for us, our email is PIMA@Freakonomics.com. That’s P-I-M-A@Freakonomics.com. We read every email it’s sent. We look forward to reading yours.

In two weeks, we’re back with a brand new episode featuring Moon Duchin. She’s a theoretical mathematician who has applied her techniques to gerrymandering, and transformed our understanding of the problem. As always, thanks for listening and see you back soon.

*      *      *

People I (Mostly) Admire is part of the Freakonomics Radio Network, which also includes Freakonomics Radio, No Stupid Questions, and The Economics of Everyday Things. All our shows are produced by Stitcher and Renbud Radio. This episode was produced by Morgan Levey with help from Lyric Bowditch, and mixed by Jasmin Klinger.  We had research assistance from Daniel Moritz-Rabson. Our theme music was composed by Luis Guerra. We can be reached at PIMA@freakonomics.com, that’s P-I-M-A@freakonomics.com. Thanks for listening.

TYSON: Anyone still use that word skyscraper?