In short
Planet Money Podcast Episode Summary
Episode Title
The History of Light (Classic)
Hosts
Jacob Goldstein and David Kestenbaum
Original Air Date
2014 Episode Description This episode explores the evolution of light from ancient times to the present day, discussing how advancements in lighting technology have influenced economic growth and societal structure.
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Key Themes and Concepts
The Evolution of Light
- Historical Challenges:
- For thousands of years, obtaining light was labor-intensive and costly. The process of making candles from animal fat involved raising and slaughtering livestock, cooking the fat, and creating wicks.
- Modern Convenience:
- Today, light is easily accessible at the flick of a switch, representing a significant technological advancement.
Economic Growth and Light
- Correlation Between Light and Economic Development:
- The episode posits that the history of light is closely tied to economic growth. Access to better lighting has allowed people to work longer hours, travel farther, and pursue a variety of professions beyond subsistence farming.
Key Historical Milestones
- Ancient Times:
- The use of animal fat and rudimentary lamps was commonplace but inefficient, with limited illumination available for a day's labor.
- The Role of Kerosene:
- In the 1850s, kerosene emerged as a game-changer, providing a cheaper and more efficient source of light compared to whale oil.
- The Electric Lamp and Edison:
- The invention of the electric lamp by Thomas Edison was significant, but its success relied heavily on financing and infrastructure (e.g., power plants).
Economic Theories
- Bill Nordhaus's Research:
- Economist Bill Nordhaus calculated the cost of light throughout history, indicating that in ancient Babylon, a day's wages only bought around ten minutes of light.
- Impact of Scientific Advancement:
- The establishment of formal scientific inquiry in the 19th century led to significant improvements in lighting technology.
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Pivotal Moments in the Episode
- Candle-Making Experiment:
- Jacob Goldstein narrated his attempt to create candles from beef fat, illustrating the labor-intensive nature of early lighting methods.
- Interview with Jane Brox:
- Brox, an expert on the evolution of artificial light, emphasized the complexity and hardship involved in historical lighting methods and the innovative spirit that drove advancements.
- Edison's Financial Backing:
- The discussion highlighted Edison's need for financial support from investors like J.P. Morgan, emphasizing that innovation cannot occur without the necessary economic infrastructure.
Future of Light and Economic Growth
- The episode concludes with a contemplation of whether the trend of continuous economic growth and improvement in technologies, such as lighting, will endure indefinitely, acknowledging potential physical limits to progress.
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Key Takeaways
- Light has historically been a proxy for economic development; as lighting technology improved, so did productivity and societal complexities.
- The transition from primitive lighting methods to modern electric light underscores the importance of innovation and economic structures in facilitating such advancements.
- Current advancements, like LED technology, continue to evolve the concept of efficient lighting, reflecting ongoing efforts in the realm of economic growth.
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Final Thoughts This episode of *Planet Money* intricately weaves together the history of light with the broader narrative of economic growth, revealing how a simple shift in technology can have profound implications for society at large.
Written by AI. May contain mistakes. Listen to the episode to check what was said.
Transcript
Automatic transcript. May contain errors.0:00This message comes from Capital One. Say hello to stress-free subscription management. Easily track, block, or cancel recurring charges right from the Capital One mobile app. Simple as that you can't it. at CapitalOne.com slash subscriptions. Terms and conditions apply. This is Planet Money from NPR.
0:25Light. It's amazing, isn't it? We have it at our fingertips with the flip of a switch or a button on our phones these days. It's a technology so convenient, so ubiquitous, you almost forget it's a thing. But the ways humans have captured and used lights have evolved. over the centuries. And with each advancement, we've been able to work longer, travel farther, invent whole new industries. You could even say that as the technology of light progresses, so does humanity. Back in 2014, David Kestenbaum and Jacob Goldstein wanted to understand that exact correlation. So they asked the question, at different points in history, how much did light cost.
1:10Here's Jacob. Long before there were light bulbs, there was fat. For thousands of years, if you wanted to light up your cave, your mud hut, or if you were really lucky, your castle, you had to find some fat, something to use for a wick, maybe some moss, maybe a piece of fabric, and you had to light it on fire. This was not easy. Even today, it's a hard way to get light.
1:35Adam and I? Yeah, hi. Do you sell fat, maybe beef fat? No. I don't carry that, no. Okay, thanks very much. Thank you. Hi, do you sell fat, like beef fat? No, we don't sell any of that. Suet? No. Okay. Okay. Thanks very much. That's a good one. Yeah, hi. Do you sell beef fat? Yeah, that we have all the time. How much is that? $2.98 a pound. Okay, great. Thanks very much. You're welcome. Bye. I got two pounds. A big, nasty lump of fat came from around the cow's kidney. I got some twine from the hardware store. And I went home to my apartment to try and make candles. God. It's a little harder to chop than you might think.
2:25It kind of sticks to itself. I put the fat on the stove. It's pretty melted. It smells really nasty. It's like animal nasty. I strained it, then I started dipping the wicks into it. Dipping, dipping. You have to let the fat dry, then you have to dip the wicks some more. More dipping. It was maybe, I don't know, 45 minutes or so of dipping. Dip, dip. I got kind of dip crazy in there.
3:04After hours of work, not counting raising the cow or killing the cow or making the twine, I had six tiny, crooked, smelly candles. Hello and welcome to Planet Money. I'm Jacob Goldstein. And I'm David Kestenbaum. Today on the show, the story of how we got from dim little candles made out of cow fat to as much light as we want at the flick of a switch. And I don't think I'm exaggerating here. This one little story, it explains why we are where we are today. Why billions of people don't have to worry about starving today. Why we aren't all subsistence farmers. Why we can afford to have artists and massage therapists and plumbers.
3:41And yes, radio reporters doing stories about the history of light.
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4:33Same goes for where you invest. Level up and invest smarter with Schwab. Get market insights, education, and human help when you need it. This message comes from Insperity. Excellence takes drive, work, perseverance. Tiger Woods brings it to the course. Insperity brings it to your business. Want to be the best? Work with the best. Insperity. How you HR matters. Learn more at insperity.com slash tiger. Jacob, you brought these scraggly little candles in the office. I'm holding them up here. They look, uh... They look a little gnarled. They're definitely not straight, and they're not, like, sleek.
5:16No, it looks like some mold has grown on a... On a string. On a string, yeah. So you brought these candles into the office here, and we wanted to show them to an expert. And we sat down with this woman, Jane Brox. Jane wrote a book called Brilliant, the evolution of artificial light. So I made a few different candles. I tried... Oh, look, they're beautiful! I thought they're beautiful, you mean a total disaster. In the olden days. If a mother was trying to teach her daughter to make candles, she would not be pleased with these candles. But we'll see what happens. I was afraid when we lit these things that we might set off the fire alarm or the sprinkler system in the office.
5:58I mean, that is how weird it is to have light from fire these days. I was afraid we weren't going to be able to light them at all. I mean, it's just beef fat and twine. But we pulled out a lighter. Oh, we have light. That's not too bad. Should we see how long it lasts? It's not pretty, but I'm very impressed. It's a beautiful color. Look at the nice yellow flame, wouldn't you say? Dude, you made a candle. Jane says that the quest for this, for something that gives you light after the sun goes down, drove people to do all kinds of things. In the United States, in the Pacific Northwest, Native Americans used dried salmon.
6:39They basically made a salmon candle. In the tropics, people would catch fireflies and try to make a kind of firefly lantern. And then there's this bird called the petrel. The storm petrel in the north of Scotland, which is a very oily seabird, which they'd catch and dry and thread a wick down its throat and then light it, and then that was a lamp. Just carry around a dead bird? Well, it would be on a table. And I would imagine they'd have a little storage area with a lot of dead storm petrels. Martha, we need another petrol.
7:20The petrol supply is getting low. These ways of making light were all a huge hassle. They took a lot of work. It was not just that I didn't know what I was doing when I made those candles. The writer Harriet Beecher Stowe said making candles from animal fat was seven times as bad as washing clothes. I mean, think about it. You've got to get a cow. You've got to raise the cow. You've got to have food to feed the cow. You've got to kill the cow. You've got to get the fat out of the cow. You've got to put the fat in your Cuisinart. Which isn't going to be invented for 100 years. From an economic perspective, if you want to try to quantify how much of a pain in the butt it is to make something, or at least how hard it is to get that thing, you can ask a simple question.
8:01How much does it cost? Bill Nordhaus, an economist at Yale a while back, got obsessed with this question. He decided he wanted to calculate exactly how expensive light was thousands of years ago and how that cost changed over time. Because light, you know, light is this thing society has needed and sought forever. It was a way to track progress, not just in light, but in all kinds of things. Unfortunately, in order to do this, he needed to know how much things cost thousands of years ago, like in ancient Babylon. He wasn't even sure those numbers existed, but they did. I ran into a woman at Yale, and she, believe it or not, it's just unbelievable, actually.
8:41She actually had wage data and price data from the Babylonian era. So 4 ,000 years ago. So now he has these numbers, but he needs to know one other thing. How much light are people getting for their money? In ancient Babylon, people used lamps for light. So Nordhaus decided to make one. I did this in my dining room. Where else? He buys an ancient-style lamp from a catalog. He gets it burning. To measure how bright it is, he borrows a light meter from a facility's guy at Yale. And he does some science. And I would just measure it and write it down, just the way you see in the old movies, some guy in his lab coat writing down the measurements.
9:26Jacob, odd little note here. I happened to be taking Nordhaus's economics class right around this time, which I will say was a pretty serious, like, no-nonsense class. And it is so funny for me to think that at night he was going home and measuring ancient lamplight in his dining room with a light meter. So he does this, the light meter in the ancient lamp, and he has his numbers. but now he has to figure out a way to compare the price of light over thousands of years. So here's one measure he uses. If you take a day's wages, you work all day, you take all the money you earn in that day, and you spend it on light, how many minutes could you light up a small room at night with as much light as you get from today's modern light bulb?
10:06Here's the answer for ancient Babylon. Maybe 10 minutes. It was really expensive. An entire day's wages got you the equivalent of 10 minutes of light from a kind of dim light bulb. Economists talk a lot about productivity, how much one person can produce with a day's labor. And back then, the answer was not much. I mean, everything was hard. Growing food was hard. Making candles, for instance, took hours. And it used up fat. Fat, which, by the way, was expensive because raising animals was hard. This was a world where when the sun went down, almost everyone lived in the dark. And this may sound sort of romantic, but basically it was awful.
10:44The dark was not some beautiful thing you went out and explored. It was dangerous. It was something that trapped you. In Paris, at one point, there was actually a law that said every night, everybody has to give their keys to a magistrate, go home, and lock themselves in the house. And for basically 4 ,000 years, very little happens with light or with the economy in general. Most people work all day, and that gets them enough to eat. The way things get better, the way an economy grows, the way people get richer, is that someone comes up with a better way to do something. A way that takes a little less work.
11:18Over time, there are small improvements in life and in light. The Romans figure out how to make a lamp that's a little more efficient. People start to use whale oil. This, of course, is very, very bad for whales. But whales have a lot of fat. They were like these big swimming sources of fuel. Still, even when you get all the way to the 1700s, life still looks more like ancient Babylon than the modern world. People still travel the same way, by foot, by horse, by sailing ship. Most people are still subsistence farmers, usually living in some kind of hut, trying to grow enough food not to starve to death.
11:53Year after year, there are tiny gains in productivity, little bits of economic growth, but not a lot. And light? Light still comes from finding stuff that's lying around and just lighting it on fire. Again, economist Bill Nordhaus. As you look at the picture of what happened here, it's economic history in a nutshell. From Babylonian times to around 1800, there were, even though there were improvements, as best we can tell, they were very modest. And then around 1800, in the lighting, you can see it so clearly in lighting. It's just an enormous change in the pace of improvement. What happens in the 1800s is a few things.
12:33We start to really actively experiment. We try to discover stuff. And around 1850, a guy in Canada comes up with something that's not just a slightly better wick or a slightly more efficient lamp. It is this magical liquid. With the right techniques, you can get it from coal or oil. This big breakthrough? Kerosene. Not cutting edge now, but back then, Jane Brock says, kerosene was a huge deal. When the first kerosene lamps came out, it was, as one historian said, it was the kind of oil people had dreamed about for centuries. It was brighter, it was cleaner, and importantly, it was much cheaper.
13:11You work a day, you get about an hour of whale oil. Kerosene, you get about five hours. Wow. So it's about five times more efficient. Kerosene lit the world and saved the whales. So if kerosene was so great, why did it take the world so long to find it? Science. This idea of professional scientists, this idea that there are lots of people who go to work every day at universities and do experiments. In the 1800s, this is still a new thing. If you happen to be president of Yale University, this is around the time when you're thinking, you know, maybe we should get one of those science departments.
13:55Why weren't they doing those experiments a century earlier? Well, Yale didn't have scientists a century earlier. They were teaching Greek and they were teaching logic. Now all these scientists are working on better ways to make light. And light is getting cheaper. More people are using it. No more locking yourself in and huddling in the dark all night. Around this time, streetlights start popping up. And people start going out at night. So we have kerosene. What's the next big advance after that? Okay, next big advance after that is the electric lamp. The big one. Well, you might think so.
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17:01How to Buy Them. It's in our latest bonus episode where we also reveal the winning name of the indicator mascot. So if you're signed up already, get that merch. If you haven't, now's your chance. Just go to plus.npr.org slash planet money. You know, Jacob, I thought I knew the story of the light bulb. You know, Thomas Edison, the great inventor, story about science and innovation. You know, Edison trying all these different filaments, these different designs, and finally getting one that'll glow for hours. But this Eureka light bulb moment, it is not, it's not enough to get you to the world of really cheap light.
17:36Because Edison needed this other thing. He needed money. He needed lots and lots of money. Why? Because he can't light a light bulb without electricity. He needed to build a power plant. So right now we're at the location of the original power plant in lower Manhattan. This is Paul Israel. He's an Edison scholar. We met him here in New York City. We're standing in front of this plaque. It says Thomas Alva Edison in big letters. And there's this picture, an etching. And the image that they show is the generator room of the power plant. With a bunch of guys in really long mustaches and hats. Right.
18:14This is 1882. So lots of mustaches in that point. The money part of building the power plant is so important that when they finally get this historic thing completed in 1882, they get the power plant built, and they're ready to turn it on. Edison is not here. He's a few blocks away at a big, impressive stone building, where today there is another plaque to a guy you may have heard of, J.P. Morgan. It reads, The capitalist's capitalist, known throughout the world of finance, sought out by presidents, helped bankroll the industrialization of America. Can't write that on too many people's plaques.
18:48J.P. Morgan's bank and a bunch of investors, they put up the money for the power plant. To be clear, they built this great, big, expensive, complicated power station, the first central power station in the world, right? Basically inventing electric light. And when they turn it on, Edison is not there. Right. Right. He was where he needed to be with the people who had funded the whole thing, right? So at 3 p.m. on September 4th, Edison flicked on the switch here at J.P. Morgan's office. And what happened? It went on. And as did lights all over the district. About a square mile of Lower Manhattan suddenly was lit by electricity.
19:28You think of Edison the inventor, but even more important is Edison the businessman. At the time, buildings in Lower Manhattan were running off gas lights, and Edison knew that was who he had to beat. So he spent a lot of time thinking about economics. Yeah, well, he did. In fact, if you look at his notebooks, constantly he's going through and comparing the cost of what he's doing to what the cost of a gas system is. You never think about that. Well, and that's what made him such a good innovator, right? Because he recognized that these economic questions were just as important in designing what he did in the laboratory.
20:03When you think of economic growth, how much do you think of it as coming from, like, individual, like, eureka moments and inventions and stuff like that? And how much is it the stuff around it, like the ability to finance these things, the economic structure around it? So most of it is actually the structure around it. To light a square mile of lower Manhattan, Edison needed a whole financial system. He needed patents, a way to protect his ideas so no one would steal them. He needed a company, a way a bunch of different investors could come together and risk money, a lot of money, to build a power plant and lay wires so you could try this crazy thing.
20:37Light without fire. Edison comes along at a time when all this machinery, patents, corporations, banks is in place. There were consequences to growth. I mean, those first power plants burned coal, and pollution was pretty bad. Edison built a huge power plant on the east side of Manhattan, and at some point the city health department got involved, and this is according to the New York Times, quote, When it was found, health department men were trying to photograph the smokestacks. Scouts were put on the company's roof, who ordered the feeding of coal stopped whenever photographers appeared. On the other hand, you now had a city lit up with cheap electric light.
21:10Tradeoffs. Around this time, everything is getting faster and cheaper. Scientists keep making new discoveries. You get the internal combustion engine, the tractor. For the first time in human history, most people don't have to work as farmers. This went on decade after decade all through the 20th century. All kinds of things got much cheaper, like light. And if you look at the really long arc here, it's amazing. I mean, go all the way back to the Babylonians, okay? Babylonians worked all day. You got the equivalent of 10 minutes, 10 minutes of light. 4 ,000 years later in the 19th century with kerosene lamps, things are better.
21:46A day's labor gets you five hours of light. And by the time Nordhaus does his light study in the 1990s, if you work a day, how much light do you get? Maybe 20 ,000. 20 ,000 hours? 20 ,000 hours, yeah. I mean, you basically, you have your house lit up, you have your streets lit up, you have all your equipment on, you have your air conditioner on, You have all the stuff you're doing. You're saturated with light. The main thing is you're saturated with light. Economic growth isn't all good. There is pollution. There are environmental consequences. But fundamentally, growth is about things getting faster, getting cheaper, getting more efficient.
22:31It's about doing the same amount of work and being able to buy 20 ,000 hours of light instead of 10 minutes. And as a result, it's about being able to work less or to buy other stuff that used to be just for the wealthy. We can buy books. we can take vacations. Even today, there are still people who go to work every day and try to figure out how to make a better light bulb. This morning, I went to the bulb factory for about an hour. This is John Edmond. He's one of the founders of a company called Creep. They make LED light bulbs, which, of course, are much more efficient than regular bulbs. You'll try and experiment, and you'll say, holy crap, we just got more light out of this thing by using this contact material or flipping the chip over.
23:16Jacob, when we talk about economic growth every year, you know, when we say the economy grew a couple percent, that happens because every day out there, someone somewhere in some corner of the economy has figured out how to do something a little bit better or a little bit faster or a little less expensively. And this process has gone on year after year for hundreds of years now. And one question I always have when I think about this is like, and not just with light, But this whole story of constant economic growth, constant productivity improvement, my question is, is it going to go on forever?
23:48Or at some point, we're going to run out of ways to make things better? We might double from where we are now, but we're not going to be tripling and quadrupling it because there are physical limits. I mean, will a car go a million miles an hour? No. It just won't. It's not going to happen. For the light bulb, at least, John says, we may actually be near the end.
24:15Oh, love that show. It originally aired in 2014. You can email us at planetmoneyatnpr.org or you can find us on all the socials at Planet Money. Today's show was originally produced by Caitlin Kenny and Damiano Marchetti. The rerun was produced by James Sneed, edited by Jenny Lawton, and engineered by Valentina Rodriguez-Sanchez. Alex Goldmark is our executive producer. I'm Nick Fountain. This is NPR. Thanks for listening and throw in a light if you don't have one on already.
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From the publisher
The history of light explains why the world today is the way it is. It explains why we aren't all subsistence farmers, and why we can afford to have artists and massage therapists and plumbers. (And, yes, people who make podcasts about the history of light.) The history of light is the history of economic growth--of things getting faster, cheaper, and more efficient.
On today's show: How we got from dim little candles made out of cow fat, to as much light as we want at the flick of a switch.
Today's show was hosted by Jacob Goldstein and David Kestenbaum. It was originally produced by Caitlin Kenney and Damiano Marchetti. Today's rerun was produced by James Sneed, and edited by Jenny Lawton. It was fact-checked by Sierra Juarez. Engineering by Valentina Rodríguez Sánchez. Alex Goldmark is Planet Money's executive producer.
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