History of the Self: Aging

49m
Defeating old age? In 1899, Elie Metchnikoff woke up in Paris to learn he had done just that. At least, that's what the newspaper headlines said. Before long he was inundated with mail from people begging him to help them live forever. The only problem? He didn't know how to do it.

At the time, Metchnikoff was one of the world's most famous scientists. And he believed aging was a disease he could cure. He dedicated his life to that quest, spending his days interviewing centenarians, pulling gray hair out of colleagues and old dogs, and boiling strawberries — all in the pursuit of eternal youth. If you've ever had yogurt for breakfast, you likely have Metchnikoff to thank. (This episode first ran as The Man Who Cured Aging)

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Transcript

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Speaker 2 Around 200 BC, China's first emperor, Qin Sha Huang, feared death so badly that he sent an alchemist on voyages across the sea to search for a magic elixir that would give him immortality.

Speaker 2 After the alchemist disappeared at sea, the legend says the emperor took things into his own hands and died after drinking what he thought was a cure.

Speaker 2 Around 200 years later, another legend was born.

Speaker 2 A holy grail that was thought to hold life-restoring powers for anyone who drank from it.

Speaker 2 There was the Philosopher's Stone, the Fountain of Youth,

Speaker 2 And then

Speaker 2 in late December of 1899, a scientist named Eli Metshnikov woke up in Paris to learn that he had done it. He had found the secret to eternal life.

Speaker 4 The French morning newspaper L'Homatin carried a huge headline in large black letters all across the front page, and it said, Vive la vie, long live life.

Speaker 2 Underneath that headline, it said things like, L'Élixir de l'Éterné Jeunesse, the Elixir elixir of eternal youth l'institutes miracles the institute of miracles la vieze vincou old age defeated

Speaker 5 none of us should despair to see the year 2000

Speaker 5 will reach the age of the patriarchs and monsieur meshnikov will be damned only by heirs of fortunes

Speaker 2 Eli Meshnikov had captured the world's attention

Speaker 2 For millennia, people had tried to evade death, seeking cures in things like mercury, gold, powders, liquids. But now they had a new tool, science.

Speaker 2 And it was miraculous. There were new vaccines, x-rays had just been invented.
You could now see what had once been invisible. And Metchnikov had helped to make that happen.

Speaker 4 He was very famous. He was one of the most famous scientists in the world.

Speaker 2 Eli Metchnikov was hardcore. The man drank cholera in the name of science.
He injected himself with disease, and he tested the body's power and its limits.

Speaker 2 Later in his career, his work on the immune system would win him a Nobel Prize. When the world was sick, Eli Meshnikov tried to cure it and he made sure people knew.

Speaker 4 He loved the journalists. He never turned them away and they loved him even more than he loved them and they followed him around and they took down his every word.

Speaker 2 And his message was clear.

Speaker 4 He thought that a solution to everything was science.

Speaker 4 So of course, science was going to solve aging as well.

Speaker 5 Aging is a disease that should be treated like any other.

Speaker 2 No one had studied aging scientifically before and here was this famous scientist saying he wanted to take it on. But Mechnikov didn't just want to study aging, he wanted to cure it.

Speaker 4 This became for him like the new mission.

Speaker 5 Science alone can lead suffering humanity into the right path.

Speaker 4 We free the world from this terrible affliction.

Speaker 5 And the world ate it up.

Speaker 4 Entire sacks of letters that piled up in the mailroom was stuffed with letters from people who didn't want to die.

Speaker 7 Nobody likes to die.

Speaker 7 Nobody likes to see their friends and family die.

Speaker 7 So we want to extend the lifespan as much as possible.

Speaker 8 People nowadays want to remain ageless.

Speaker 3 We can delay aging.

Speaker 9 It's one of the foundational questions in science.

Speaker 2 We can stop aging.

Speaker 9 How long can we live?

Speaker 7 We keep searching.

Speaker 6 What is it exactly we're looking for?

Speaker 10 I don't know what I want to do.

Speaker 6 Living to 200? Are we looking to living to

Speaker 11 you know, 95 with our senses and being active and in control?

Speaker 8 I think the most important thing to me is maintaining my mobility.

Speaker 12 I would love to like renovate a a house. I think I want to travel more.

Speaker 8 Traveling as much as I can.

Speaker 12 More time to myself.

Speaker 9 We all know that winter is coming for us.

Speaker 12 We have about 20-25 years left.

Speaker 9 The question is: when and can we push it out as much as possible? People have been talking about it for thousands of years.

Speaker 9 It's not a new question, it's an old question.

Speaker 2 Since the beginning of human civilization, people have been obsessed with staying young, even living forever. Today, that obsession is tied up with media, medicine, and money.

Speaker 14 So I got this draw on Amazon, and it literally is the best.

Speaker 2 We spend billions of dollars on anti-aging products.

Speaker 13 It doesn't cause wrinkles, you can easily drink out from the top of it.

Speaker 2 We're told to look younger. The top 10 celebrities who have aged badly.
We question whether older people are fit to lead.

Speaker 15 Why do voters vote for older politicians and then turn around and question their mental fitness?

Speaker 2 But what if these are the wrong questions? Is aging something we even need to cure? And what does it mean if we can't? I'm Ramteen Arab Louis.

Speaker 16 I'm Randal Defatar.

Speaker 2 On this episode of Through Line, We're not going to answer the question of aging, but we are going to tell you the story of someone who tried.

Speaker 16 It's part of our series, History of the Self, where we explore the deeply personal experiences that make history.

Speaker 2 Coming up, our producer Devin Katayama tells the story of Eli Meshnikov.

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Speaker 7 Part 1.

Speaker 14 This love of life.

Speaker 10 The country is neither beautiful nor rich. Steppes, hillocks covered with low grasses and wild warm wood.

Speaker 10 A poor village, meagre vegetation, no river.

Speaker 10 The whole impression is a melancholy one.

Speaker 3 In the middle of the 19th century, Ilya Ivanovich and his wife and children left St. Petersburg, Russia for the countryside.

Speaker 10 But what boundless space, what soft, silver-gray coloring, and in the mornings and evenings, what fresh, cool air.

Speaker 3 It was here on a little slice of land outside the main village that they would welcome their fifth child into the world.

Speaker 10 Though they wished to have no more children, one more child was born on the 16th May, 1845,

Speaker 10 Eli Mechnikov.

Speaker 3 These descriptions of Eli Mechnikov's early life are from the biography his wife Olgo wrote about him.

Speaker 10 Fair and slender, with silky hair and a diaphanous pink and white complexion, he had small grey blue eyes, full of kindliness and sparkle.

Speaker 7 He had a few brothers and sisters, and out of all of them, he was probably the most curious.

Speaker 10 He was so restless that he went by the name of Quicksilver. He always wished to see everything, to know everything, and found his way everywhere.

Speaker 7 As a kid, he was always chasing bugs and looking at what bugs do.

Speaker 10 He could only be kept quiet when his curiosity was awakened by the observation of some natural object, such as an insect or a butterfly.

Speaker 7 Then he would invite all of his siblings and cousins for a lecture in natural history, and he would actually pay them out of his pocket money to come and listen to his lectures.

Speaker 3 This is Lina Zeldovich. She's currently a science and medical journalist in New York City, but she grew up in the former Soviet Union, where Eli Mechnikov was a household name.

Speaker 7 So I learned that name at a very young age.

Speaker 3 She remembers hearing about his famous discoveries, the same way you might have learned about Albert Einstein's E equals MC Square.

Speaker 7 He was like, you know, a cherished name, a big name.

Speaker 7 A couple of research institutions were named after him. We definitely knew about him growing up.

Speaker 3 Mechnikov was born in a time and place when medicine was only just starting to modernize. The human body wasn't really understood, and diseases like cholera and typhoid were really scary.

Speaker 3 Many doctors still believed in bloodletting and would actually treat patients with toxic substances like mercury and lead. So medical care itself was basically synonymous with suffering.

Speaker 7 From a very young age, I think he had this desire to alleviate human suffering, and that's how he sort of found his way into biological research.

Speaker 3 So Metchnikov grows up to become a zoologist, and he couldn't have picked a better time because when he was just 14 years old, a new theory rocked the scientific world.

Speaker 3 Charles Darwin's theory of evolution.

Speaker 4 The main goal at the time of many scientists and of him as well was to test Darwin's idea that all life on Earth came from the same same common ancestor.

Speaker 3 And he dedicated his early career to researching that theory.

Speaker 4 When he was in his late 30s, he traveled to Italy, to the island of Sicily, to study marine animals. And he was studying the larva of starfish.

Speaker 3 This is Luba Vakonski. She's a science writer at the Weizmann Institute of Science in Israel.

Speaker 4 And I've written a book called Immunity, How Ilai Mechnikov Changed the Course of Modern Medicine.

Speaker 3 This trip to Sicily would change everything for Mechnikov. He and his wife were staying by the seaside in a cottage overlooking the bright blue Messina Strait.

Speaker 3 The strait was home to all sorts of marine creatures.

Speaker 3 And while his wife went out to explore Sicily, Mechnikov would spend long days holed up in the cottage staring at jars filled with seawater and tiny organisms.

Speaker 3 One day, he had his eye pressed up against his microscope, peering inside these minuscule starfish larvae.

Speaker 4 And in the larvae, he saw mobile cells.

Speaker 3 These were cells that wandered inside the larva, gobbling up food and other particles.

Speaker 3 Meshnikov had seen these cells in action before, but that day, watching them go about their business, it struck him.

Speaker 4 He came up with the idea that maybe this is a defensive force of the organism.

Speaker 5 Sensing that my hunch concealed something particularly interesting, I became so excited that I began striding up and down the room.

Speaker 4 He performed an experiment, it's a very famous experiment in immunology, where he inserted thorns into these larvae.

Speaker 3 If the cells attacked the thorn as a foreign invader, his theory would be correct.

Speaker 4 And he saw that the cells indeed ganged up on the thorns.

Speaker 4 This was for him evidence of his theory that they were there to protect the larva.

Speaker 3 Watching this unfold through his microscope, his mind was blown.

Speaker 4 In fact, this was the first material evidence of inner healing forces in science.

Speaker 3 The invisible had become visible. Metchnikov wasn't the first person to observe this healing force, but he was the first person to define it as an immune response.

Speaker 3 This was the work that would later earn him a Nobel Prize.

Speaker 4 The idea that the body has inner powers that can be studied and enhanced and understood, I mean, that's enormous. It just turned everything around.

Speaker 3 Around the turn of the century, while Mechnikov was consumed by his work on immunity, another question started to nag at him.

Speaker 4 He was living in Paris and working at the Pasteur Institute.

Speaker 3 The Pasteur Institute was home to the miracle makers of the day, scientists who were researching vaccination or figuring out what caused plague.

Speaker 4 He was in his mid-50s.

Speaker 4 He started having kidney trouble

Speaker 4 and he began to worry about his own aging.

Speaker 4 And he also began to fear death.

Speaker 5 Our strong will to live runs counter to the infirmities of old age and the shortness of life. That's the greatest disharmony of human nature.

Speaker 3 Life expectancy at the time was around the mid-40s, so he must have had a growing sense of his own mortality. But he wasn't just concerned about himself.

Speaker 3 In his mind, aging was one of the greatest problems facing humankind. The fact that we all grow older, and that aging meant sickness until death.

Speaker 4 And he was appalled to discover how little was known about aging and that there was no systematic study of aging.

Speaker 4 There were textbooks about diseases of old age but not about old age itself.

Speaker 3 And Meshnikov comes up with this theory,

Speaker 3 an idea that would stay with him throughout his entire life.

Speaker 4 His hope was that if people live long enough, they will develop this death instinct.

Speaker 3 The death instinct.

Speaker 5 This instinct must be accompanied by marvelous sensations, better than any other we are capable of experiencing.

Speaker 4 Death instinct would mean that people would be happy to die after living a long and healthy lives.

Speaker 5 Perhaps the anxious search for the purpose of human life is nothing but a vague yearning for this anticipation of natural death.

Speaker 4 He went around looking for this death instinct.

Speaker 3 He became so obsessed with figuring out how older people felt as they approached death that he would literally chase the elderly down.

Speaker 4 Centenarians made it into the newspapers. So whenever he would see an article about an old person, he rushed to meet them and he wanted to ask them, you know, about if they wanted to die.

Speaker 6 So this is late 19th century. We're going through a transformation from the agrarian economic system to the industrial economic system.

Speaker 3 This is Carol Haber. She's a professor and dean emerita of Tulane University in the School of Liberal Arts.

Speaker 6 I was trained as a medical and social historian, and I focus largely on the history of aging.

Speaker 3 Carol says she doesn't think there was ever a time when old age was seen as something wonderful, that everyone respected.

Speaker 3 But around the time Mechnikov turned his attention attention to aging, there was a cultural shift happening in how people viewed it.

Speaker 6 If you look at the late 19th century, the image of the old person is hunched over with a cane, sitting in a rocking chair. It's pretty negative.

Speaker 3 At that time, the Industrial Revolution was changing how families lived and worked. And in this work revolution, the elderly were getting left behind.

Speaker 11 You had the feeling that there wasn't this basis of support and that old people were going to end up in what they called the industrial scrap heap.

Speaker 11 They couldn't keep up, they couldn't learn new skills, and so they were going to become oxilensen.

Speaker 3 Western society's view, whether it was true or not, was that the elderly weren't compatible with the increasingly fast-paced world. Caring for the elderly came to be seen as a burden.

Speaker 3 Many elderly people ended up living the rest of their days in a hospital. And that's exactly where Mechnikov went to find them.

Speaker 4 He went to this large French hospital, La Salpêtrière.

Speaker 3 La Salpêtriere was an infamous hospital in Paris. It had long doubled as a psychiatric ward and a home for the elderly.

Speaker 4 And most of them were poor because, you know, obviously more wealthy elderly wouldn't make make it there.

Speaker 3 For a lot of Parisians, it was a dark, distant presence looming over the city.

Speaker 3 Inside its imposing brick walls was a massive, sprawling complex that for centuries had been a place of squalor and suffering.

Speaker 3 A famous French neurologist referred to it as Le Versailles de la Douleur,

Speaker 3 the Versailles of Pain.

Speaker 4 Probably must have been

Speaker 4 quite a sad place, you know, where all these people were brought to die and there was not much that could really be done for them.

Speaker 3 But it was the perfect laboratory for Mezhnikov.

Speaker 4 He went around asking them what they wanted and he was hoping to find the death instinct.

Speaker 4 And he was really disappointed because even the sick, old people, they didn't want to die, they wanted to get better.

Speaker 5 I discovered that one and all felt as if they were continually being threatened by death, as if they were convicts awaiting the day of execution.

Speaker 5 At the Selpetre, the great ambition of women of 80 is to live to 100, and the desire to live is almost universal.

Speaker 3 Even in a miserable place like Salpatrière, people wanted to live longer.

Speaker 5 What is this love of life that makes death so terrible?

Speaker 4 He developed a whole philosophy that there was this big disharmony in the world, you know, in nature, between the shortness of human life and

Speaker 4 people's desire to live.

Speaker 3 Metchnikov came to believe that aging was a disease, and he was sure that science could cure it. He envisioned a utopic future where medicine could prolong life up to 150 years.

Speaker 3 At that age, he thought, the death instinct would finally appear.

Speaker 3 So, he went all in.

Speaker 4 This became for him like his new mission to free the world from this, you know, this terrible affliction.

Speaker 3 Coming up, Metchnikov heads back to the lab with a new mission to extend human life to 150 years.

Speaker 17 Hello, this is Nancy Smith, and I'm in Kiel, Germany. You're listening to ThruLine from NPR.

Speaker 17 It's a great show. I love it.

Speaker 5 Keep up the good work.

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Speaker 5 Part 2:

Speaker 14 Trusting his gut.

Speaker 3 In his 20s, Eli Mechnikov had been visited by death.

Speaker 7 His first wife died of tuberculosis.

Speaker 7 It's a disease that kills you slowly.

Speaker 7 You can basically watch your loved one wither away.

Speaker 7 day after day and month after month.

Speaker 7 They traveled to places with better climate,

Speaker 7 milder winters, sunnier places, and nothing happened. She eventually died.

Speaker 3 This sent Metchnikov into a deep depression. And then a decade later, he went through it again.

Speaker 7 His second wife contracted typhoid fever and it looked like

Speaker 7 she could die and so he inoculated himself with some kind of a tig-borne disease, thinking that they will die together.

Speaker 7 But neither one of them died.

Speaker 3 And this changed everything. for Metchnikov.

Speaker 10 After his recovery, he had a renaissance of vital intensity. The life instinct developed in him in a high degree.

Speaker 10 His health became flourishing, his energy and power for work greater than ever, and the pessimism of his youth began to pale before the optimistic dawn of his maturity.

Speaker 3 Fast forward a couple of decades. It's the early 1900s.
The now famous Metchenkov set out to pioneer the study of aging and cure it.

Speaker 3 He wants people to be able to live happy and healthy until they're ready to die.

Speaker 5 The purpose of human existence lies in going through a normal cycle of life, leading to a loss of the life instinct and a painless old age, bringing about a reconciliation with death.

Speaker 3 By now, he's a superstar at the Pasteur Institute, which was one of the most prestigious science facilities in the world at the time. It's sort of a scientist's dream.

Speaker 3 He has lab assistants, facilities, all the resources he could imagine at his fingertips, and he gets to work.

Speaker 4 His lab gradually filled up with old animals of all sorts.

Speaker 3 There are mice and rats and geese and cats and dogs. There's this 87-year-old turtle and a 70-year-old parrot.

Speaker 4 Meshenkov was very happy that he was still interested in females.

Speaker 3 And that's just the beginning. He starts pulling out hair from an old great Dane, from a co-worker, and then from his own head to figure out why it's turning gray.

Speaker 3 And remember, he's a renowned immunologist with kind of a savior complex. So he's also spreading the gospel to everyone he knows.

Speaker 4 When he rode on public transportation, he would tell people how they should be careful about microbes.

Speaker 4 He boiled everything he ate.

Speaker 4 Even strawberries and even peeled bananas. He thought that the skin probably didn't protect them well enough.

Speaker 4 And when he invited guests to restaurants, he asked to bring a burner and he sterilized the utensils.

Speaker 3 Okay, so maybe he's not like the most fun guy to have around, but this is the beginning of the science of aging, of gerontology, which, by the way, was a term that Metchnikov coined in 1903.

Speaker 3 And science is all about making mistakes, so you can find that one thing that works. And as he's conducting all these experiments, he zeroes in on this one idea, that the body was being poisoned.

Speaker 4 He thought that the root of aging that it all started in the intestines.

Speaker 3 Specifically, the large intestine.

Speaker 5 The large intestine must be regarded as one of the organs possessed by man and yet harmful to his health and his life.

Speaker 5 The presence of large intestine in the human body is the cause of a series of misfortunes.

Speaker 3 The idea that something bad was happening in the intestines is one that dates back thousands of years. So this wasn't necessarily a new idea.

Speaker 3 But in the late 19th century, it was making a comeback because science was making new links to germs and disease.

Speaker 7 At the time, the human intestine was viewed as a cesspool of all sorts of toxins. I guess the proof that all the scientists had was: no, hey, just look what comes out of your rear end.

Speaker 7 Any more questions?

Speaker 4 So Meshinkov thought that in the intestines there are microbes that cause rotting, and that the rotting is what really causes the deterioration of aging.

Speaker 4 The big question became how to fight that.

Speaker 3 Then one day, he has a breakthrough.

Speaker 4 He learned that in Bulgaria there is this entire population of centenarians in the mountains.

Speaker 3 Remember, Mechnikov is obsessed with centenarians, and there were newspaper articles backing up this idea that people in this region of Bulgaria were living a long time. And so he had to know why.

Speaker 4 Yogurt.

Speaker 3 Yogurt.

Speaker 4 They ate lots of yogurt.

Speaker 3 Mechnikov had to tell everyone.

Speaker 3 It's 1904, Paris, a crowded lecture hall at the Society of French Agriculturalists. The famous Eli Mechnikov is the guest speaker.

Speaker 4 The lecture was called Old Age.

Speaker 3 And he starts by getting up there and rattling off some pretty dark ideas.

Speaker 4 He was saying how in Europe old people are miserable.

Speaker 5 Their lives often become very difficult, unable to fulfill any useful role in the family or in the community. Old people are considered a very heavy burden.

Speaker 3 He claimed they were more likely to commit suicide or be murdered.

Speaker 5 One is shocked by the quantity of murders committed against the elderly, notably against elderly women.

Speaker 3 He also repeated, without evidence, by the way, that some cultures killed and ate their women.

Speaker 4 Because they are useless. And he said that people there say that old dogs can at least capture seals and old women can't even do that.

Speaker 4 He was painting a very sort of gruesome picture of old age.

Speaker 3 Metchnikov is straddling the line between serious science and being a salesman because he's still trying to sell the world on science.

Speaker 3 So he's playing to his audience, stoking the fears of aging that are growing at the time and then saying, hey, don't worry, science has the solution.

Speaker 4 He brought an old dog and a parrot.

Speaker 4 The dog was 17 and he looked very old and undecrypted. And the parrot, who was 70, looked much younger than the dog.

Speaker 3 And then Metchnikov lays down his science.

Speaker 4 Birds do not have such large intestines as mammals. They don't store as many microbes.

Speaker 3 And he says, if we can find a way to prolong that decay in our intestines, then maybe we can prolong it in the rest of our bodies.

Speaker 4 And then he says, maybe there's a solution because, you know, in Bulgaria, people live that long.

Speaker 5 It is interesting to point out that this microbe is found in sour milk consumed in large quantities by Bulgarians in a region renowned for the longevity of its inhabitants.

Speaker 4 He connected all these dots together.

Speaker 4 We age because in the intestines there is rotting.

Speaker 4 And lactic acid that is produced in sour milk can stop this rotting by killing the bacteria that cause the rotting. And there you have proof.

Speaker 4 all over the world, the newspapers started running running stories.

Speaker 6 The Chicago Daily Tribune.

Speaker 19 Sour milk is elixir. Secret of long life discovered by Professor Meshnikov.

Speaker 4 And there was no turning back.

Speaker 19 Drink sour milk and live to be 180 years old.

Speaker 4 I mean, this started a real mania, yogurt mania.

Speaker 3 The London Telegraph, the Washington Post.

Speaker 19 People who wish to live to 100 breakfast off of yogurt exclusively.

Speaker 3 That one lecture, Luba says, started a global yogurt trend that still exists today.

Speaker 4 I think it's rare to trace the beginning of an industry to a single event.

Speaker 4 But in this case, I can pretty much, I can say, you know, that the yogurt industry started with that lecture.

Speaker 3 Much later, we'd find out that yogurt was probably not the only reason people in that region of Bulgaria lived so long. But it didn't really matter.
Pharmacies started stocking yogurt.

Speaker 3 Doctors recommended it to patients. People used it as a disinfectant or preparation for surgery, even to treat some diseases.

Speaker 5 This stuff was all over the place.

Speaker 4 There were ads, this cafe on one of the Parisian boulevards advertised Bulgarian curdled milk.

Speaker 7 The yogurt crease kind of, you know, grew and grew.

Speaker 4 I saw pictures of Danona, which I think in the States is called Dannon.

Speaker 3 Yeah, Dannon yogurt.

Speaker 7 I mean, I don't even know how many different brands of yogurt we have today, but Dannon is still there.

Speaker 3 Even breakfast cereal pioneer John Harvey Kellogg reached out to Mechnikov. His face was everywhere.

Speaker 4 They sold cups of yogurt and it said, recommended by Professor Metchnikov and the medical profession.

Speaker 4 It was totally got out of hand, completely.

Speaker 4 There was all this hype and all this hoopla about it that he had no control over.

Speaker 3 This wasn't exactly what Mechnikov had wanted. Throughout his career, he was always arguing over how the media took his research and ran with it or twisted his words.
He gave caveats to his work.

Speaker 3 He called his ideas theories.

Speaker 4 He tried sort of to present the facts and to separate it from the hype, but it was just way too late.

Speaker 4 The good thing about yogurt was that it was harmless, you know, because so many cures for aging were, you know, terrible and dangerous and lethal.

Speaker 4 And yogurt was cheap and it was safe and easily available so it was irresistible

Speaker 3 mechnikov was a scientist but he was also a showman maybe yogurt wasn't a magic elixir but science would still find the answers

Speaker 3 Coming up, Metchnikov returns to Russia to face one of his biggest critics. He's 63 years old and he doesn't know it yet, but he's running out of time.

Speaker 3 Hello, world.

Speaker 17 I'm Charles Smith from Zurich in Switzerland, and you are listening to TrueLine from NPL.

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Speaker 14 Part 3.

Speaker 14 Winter is coming.

Speaker 10 It was at dawn that we reached the little railway station where a garage had come to meet us.

Speaker 3 On a cloudy May morning in 1909, Eli Mechnikov, bow tie and great coat, and his wife Olga, white blouse, straw hat, descend from an overnight train.

Speaker 10 We were excited by the sight of the Russian country. Cool meadows, forest, fields, all that simple landscapes that we had not seen for so long.

Speaker 10 And we were also greatly moved at the idea of meeting Tolstoy.

Speaker 3 Metchnikov has returned to Russia, where he was born, to visit the writer and philosopher Leo Tolstoy.

Speaker 4 So he was looking to sort of solve the riddle of aging on all levels.

Speaker 4 He was looking for partners in this quest.

Speaker 5 I had long wanted to get to know Tolstoy closer, learning in person what he really thought about universal issues that had fascinated me since my youth, especially the basis of morality, the meaning of life, and the inevitability of its end.

Speaker 4 He admired so much Tolstoy's writing about the fear of death, which are really masterful.

Speaker 9 A man

Speaker 4 So he thought that Tolstoy must know some secret that I don't.

Speaker 3 This wasn't just some random meeting. Although the two had never met, their work had been in conversation for years.
Tolstoy was critical of Mechnikov's work and threw shade on science in general.

Speaker 9 Scientists can tell useful knowledge from useless.

Speaker 9 They study such topics as the sexual organs of the amoeba only because this allows them to live like lords.

Speaker 3 And Mechnikov had written responses about Tolstoy, warning of the dangers of discarding science and embracing just spirituality.

Speaker 5 In certain cases, his teaching had caused young researchers to drop science, burn their dissertations, and join communes to start a new life.

Speaker 3 Now it's time to talk face to face. Metchnikov had minds.
Now he needed hearts.

Speaker 3 At Tolstoy's estate, Metchnikov notes its simplicity. The furniture functional but old, any airs of luxury done away with.

Speaker 3 Tolstoy, 80, with a white flowing beard and white shirt, bounces down the stairs full of energy.

Speaker 4 The reporter called it a meeting of two monarchs of universal literature and science.

Speaker 3 The two spend the day together debating science versus religion. Debating as they ride in a carriage.

Speaker 3 Debating after listening to piano works by Chopin.

Speaker 3 Debating over tea.

Speaker 9 I highly value genuine science, one that is interested in man, his fate, and happiness.

Speaker 5 Any ideal that may be capable of uniting mankind in some religion of the future must be based on scientific principles.

Speaker 3 For Metchnikov, science and reasoning, always key.

Speaker 5 For Tolstoy, morals above all.

Speaker 9 If we are going to submit everything to reasoning, we can arrive at the most absurd nonsense. I dare say, in that case, it would be possible to justify cannibalism.

Speaker 5 Progress doesn't necessarily have to be based on people's love for one another.

Speaker 9 When it came to Mechnikov's current work on aging, the trouble is not that our life is too short, but that we live badly, contrary to our own conscience.

Speaker 4 So the only thing on which they agreed was yogurt, because Tolstoy turned out, loved yogurt.

Speaker 4 but other than that it was pretty much a disaster the meeting. Meshikov very candidly, very honestly wrote about this himself afterwards.

Speaker 5 Tolstoy noted that at the end of the day our world views coincide but with this difference he takes a spiritual perspective and I take a material one.

Speaker 4 Meshikov was much more spiritual than Tolstoy gave him credit for. He did try, I think, understand human psychology.

Speaker 4 And I think he thought that somehow, together with Tolstoy, he could get closer to cracking this riddle of, you know, what really happens in the human psyche, in the human mind, how, you know, we feel like that, how we feel when we age, why, you know, this fear of death.

Speaker 4 And of course, it just, you know, totally crashed. You know, the meeting didn't work at all.

Speaker 3 And Tolstoy and Menshnikov's dispute of science versus religion fit into this larger European debate at the time over how to view and improve life.

Speaker 4 At the turn of the 20th century, this was a very dominant dichotomy between pessimism and optimism.

Speaker 4 Sort of your belief about the world.

Speaker 4 Is the world getting better?

Speaker 3 For Tolstoy, the answer was no.

Speaker 3 So morality, love, and faith in the here and now was the most important.

Speaker 3 But Metchnikov, an optimist, saw things differently.

Speaker 3 In headlines, the New York Times had crowned him the apostle of optimism.

Speaker 3 But of course, he continued to age.

Speaker 4 In some of the Russian newspapers, he was bragging about how good he felt.

Speaker 4 He was saying that this is working. Look, you know, I'm eating yogurt three times a day.
I believe, you know, it's doing me a lot of good. And look how vigorous I am.

Speaker 3 Metchnikov's outwardly positive science will save us all outlook was getting harder to maintain. In 1914, as his research continued, the headlines made a dark world impossible to ignore.

Speaker 20 Assassin's bullet strikes down Archduke Ferdinand of Austria. Germany declares war on Russia.
England declares war on Germany. 25,000 dead and wounded.
Peace refused by France.

Speaker 20 War declared, all Europe in turmoil.

Speaker 4 What really killed him was World War I.

Speaker 4 He was such a believer in rational thought in science.

Speaker 4 He thought that there will be no more wars,

Speaker 4 that the world had learned from that. And he was devastated when war broke out and all science stopped at the Pasteur Institute.

Speaker 3 Over 100 people at the Pasteur Institute get recruited to the war effort.

Speaker 4 His wife describes it like how overnight he turned into an old man.

Speaker 10 He could not bear the idea, now a terrible reality, that these brilliant young lives should be sacrificed.

Speaker 3 War, she wrote, became a dark, sinister background to his daily life.

Speaker 3 And even though he had tried to convince Tolstoy that science had the answers to everything, That now looked empty in the face of a world war.

Speaker 3 He'd always thought his purpose in life was to help people reach their death instinct, right? To live longer and live healthier until they felt ready to go.

Speaker 3 The idea that humans would willfully create so much death crushed him.

Speaker 10 The contrast between his aspiration and the cruel reality had been to him a blow which his sensitive and suffering heart was not fit to bear.

Speaker 4 In 1916, so this is already what, like more than a year after the war started, his health

Speaker 4 began to deteriorate and he developed heart disease, heart failure.

Speaker 4 In terms of the fear of death, he kept coming back to this and he kept saying that I have conquered my fear of death, I have conquered it.

Speaker 4 And the truth is that you end up feeling the exact opposite because, had it been true, I don't think he would have had the need to repeat it so many times.

Speaker 4 So, it was obviously something that he was still struggling with, I think, till the end of his life.

Speaker 5 Let all those who expected me to live 100 years or longer forgive me my premature death.

Speaker 7 So he died from a heart attack.

Speaker 7 And the moments before he died, he asked his assistant

Speaker 9 to

Speaker 7 carefully look into his intestines and see what's there once he was gone.

Speaker 4 He died in 1916 at 71, not even halfway to the 150 that he thought, you know, people should live.

Speaker 4 Many people were all over the world, were disappointed. There were headlines saying, you know, what have you done? You know, we believed, you know, because even despite all the skepticism,

Speaker 4 I think people wanted to believe that maybe it's true, maybe he has found a recipe, a cure.

Speaker 5 What's the secret to a good life?

Speaker 10 I don't know what I want to do.

Speaker 5 I don't know what I want to do.

Speaker 5 I want to have a baby.

Speaker 5 Aging is not inevitable anymore. Companies are betting big money on it.

Speaker 3 If we can slow aging enough, then we will be happy.

Speaker 4 If you're concerned about preventing or minimizing the signs of aging, then this video is further than lining anti-aging food drugs that can slow down the aging process.

Speaker 9 You know, we should all be so lucky to age and grow old. and get to experience this part of life.

Speaker 9 When you try and imagine it when you're younger, you think you may not want to be there because you get these images in your head of being bent over, you know, using these walkers, and you don't want that to happen to you.

Speaker 9 But once you get out here, you know, you look around and you go, hey, nothing's different. I'm just older.

Speaker 3 This is Jay O'Shansky, professor of public health at the University of Illinois at Chicago. He's one of the people today following in Eli Metchnikov's footsteps.

Speaker 3 Been working in the field of aging for almost 40 years, trying to figure out why people live as long as we do and how to make that last even longer.

Speaker 3 In the year 2000, a few years after Eli Metchnikov would have turned 150, Jay made a bet.

Speaker 9 Basically, the bet was all about whether or not anyone alive in the year 2000 would be alive in the year 2150.

Speaker 3 Could science keep someone alive until they're 150 years old?

Speaker 9 My good friend thought that it was possible, and I said, No, it's not possible.

Speaker 9 The process of living itself leads to the degradation, the continuous degradation that ultimately leads to the demise of mind or body. And we have components of the body that don't replicate.

Speaker 3 Muscle fibers, brain neurons, parts of our bodies that power on life and degrade as you age.

Speaker 9 Those are our Achilles heels. So we can't get these bodies to last that long unless we turn the engine of life off.
And when when you turn the engine of life off, you're dead.

Speaker 3 But Jay believes in the promise of science. It's taken us so far already.
People live much longer than they did in Mechnikov's day.

Speaker 3 Jay thinks science will take us even farther so that we can live healthier longer.

Speaker 9 Do I know which one of these interventions is going to succeed? No, I don't know. All we need is one that does.

Speaker 3 The human desire to beat aging began way before Mechnikov and will likely last way after Jay.

Speaker 7 Nobody likes to die.

Speaker 7 So we want to extend the lifespan as much as possible and health span as much as possible. Kind of just how Mechnikov envisioned.

Speaker 7 And with that goal, we keep searching.

Speaker 9 Winter will come for me.

Speaker 9 It will come for all of us. The question is: when, and what can we do to do what's the most important thing, in my view, which is to enjoy life while we're here?

Speaker 9 We only get to go through this journey once,

Speaker 9 and

Speaker 9 you know, for humans, it's about 29 to 30,000 days. That's all we get.

Speaker 9 It, you know, varies, but that's it. 29 to 30,000 days.

Speaker 9 That's it.

Speaker 3 Though in some ways, some of us get more than that. Eli Mechnikov wasn't able to beat aging, but he's still with us.
In fridges and on breakfast tables, everywhere.

Speaker 6 That's it for this week's show.

Speaker 16 I'm Randabdit Fattah.

Speaker 2 I'm Ram Tin Arabloui, and you've been listening to Through Line from NPR.

Speaker 16 Next week in our series, The History of the Self, we explore what's hiding in our dreams.

Speaker 7 Dreams are a process of adaptation.

Speaker 9 Dreams have to do with preparing the dreamer for the next day.

Speaker 2 They're not random at all.

Speaker 16 This episode was produced by me.

Speaker 18 And me, and Lawrence Wu, Julie Kane, Anya Steinberg, Casey Minor, Christina Kim, Devin Katayama, Peter Balinon Rosen, Thomas Liu.

Speaker 12 Irene Noguchi.

Speaker 2 Thanks to Leslie Kossoff, Susan Evans, Sam Evans, Carol Hacker, Stefan Hubanoff, and Anandita Bolero.

Speaker 2 Also, thanks to Sasha Solieva, Zachar Kincerski, Ardem Kudznisov, Peter Balinan-Rosen, Anya Steinberg, Thomas Liu, and Laurent LaSablier for their voiceover work.

Speaker 16 Fact-checking for this episode was done by Kevin Vogel.

Speaker 2 This episode was mixed by Maggie Luthar. Thanks to Johannes Durgee, Eve Chapin, Colin Campbell, and Anya Grundman.

Speaker 16 Music was composed by Ramteen and his band Drop Electric, which includes Anya Mizani, Naveed Marvy, Show Fujiwara.

Speaker 2 And finally, if you have an idea or like something you heard on the show, please write us at throughline at mpr.org.

Speaker 16 Thanks for listening.

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