The Turing Problem

Summary

Radiolab – "The Turing Problem"

Date: March 19, 2012
Hosts: Robert Krulwich (host for episode), Jad Abumrad (brief appearances)
Guests: David Levitt, Jana Levin, James Gleick

---

Episode Overview

This episode of Radiolab delves into the life, work, and persecution of Alan Turing—mathematician, codebreaker, and pivotal figure in the creation of modern computer science and artificial intelligence. The hosts and guests explore Turing’s personal trials, his monumental contributions during WWII, and his revolutionary thinking on machines and intelligence. The discussion weaves personal biography with philosophical debate, examining not just what Turing achieved, but how his legacy resonates with ongoing questions about the nature of mind, machine, and humanity.

---

Major Topics & Discussion Points

1. Alan Turing’s Arrest and Conviction (01:44–03:31)

• Introduction to Turing’s Downfall: The episode opens by describing Turing’s 1952 burglary, which led to his exposure and arrest for homosexuality, still a crime in England at the time.
• Reactions and Laws:
  • Turing matter-of-factly identified the thief as an acquaintance of his boyfriend.
  • Jana Levin: "There was a law in England which criminalized, quote unquote, acts of gross indecency between adult men in public or private." (03:02)
• Outcomes: Turing is sentenced to chemical castration—estrogen implants—as an alternative to prison.

Notable Moment:

• Robert Krulwich: “When I learned this, I wondered if those policemen had any idea that the guy they were arresting was... one of the great minds of the 20th century, a war hero who... shortened World War II by at least two years.” (03:30)

---

2. Early Life and Loss (03:31–06:07)

• School Years: Turing is depicted as a socially awkward, bullied but intellectually vibrant adolescent at boarding school.

• First Love: He develops a bond (and unrequited love) for Christopher Morcom, a fellow student.

• Correspondence After Loss: After Morcom’s sudden death, Turing maintains a relationship through letters to Morcom’s mother, revealing deep emotional and philosophical struggles.

  • Alan Turing (letter): “I feel sure that I shall meet Morecambe again somewhere, and there will be some work for us to do together, as I believe there was for us to do here...” (05:27)

• Loss of Faith: Turing’s early religious faith fractures under the pain of bereavement.

  • David Levitt: “Turing begins to lose his faith and eventually comes to this sort of brutal conclusion that when Chris was gone, he was gone.” (05:52)

---

3. The Invention of the Turing Machine (06:07–09:18)

• Academic Development: At King’s College, Cambridge, Turing thrives as a mathematical loner given to vivid abstraction and solitary inspiration.
• Birth of the Turing Machine:
  • James Gleick: “It’s the world’s most impractical machine... but it's very simple. Number one, piece of tape, infinitely long... Number two, something that reads or writes ones and zeros... Number three, a set of instructions.” (07:07)
• Core Insight: The Turing machine abstracts computation as a series of mechanical, logical steps—a concept underpinning all modern computers.
  • Jad Abumrad: “Anything that could be done in mathematics mechanically could be done by his imaginary idiot simple machine.” (08:00)
• Discussion of Genius: The guests note how extraordinary it was, at the time, to imagine a single device capable of handling all forms of calculation and logic, rather than task-specific machines.

Memorable Quote:

• Jad Abumrad: “Turing’s machine is Cézanne’s watercolors. It’s Bach’s Prelude. He was a lonely 22 year old just thinking and he invented a thing that lives in the minds of every computer scientist today.” (09:18)

---

4. Codebreaking and Wartime Heroics (09:51–13:05)

• World War II & Enigma: Turing is recast as the prime intellect driving the decryption of German military code via the Enigma machine.
  • David Levitt: “They changed the settings every transmission... It was considered by both the Germans and the British to be uncrackable.” (10:23)
• Formation of Bletchley Park Team: An unconventional team is assembled: mathematicians, chess players, and crossword experts.
  • Jana Levin: “But the architect of the effort was really Alan Turing... he was the one who... had a very typically Turing-ish sort of breakthrough.” (10:54)
• Turing’s Machine ‘the Bombe’: He built a room-sized electromechanical device for codebreaking, exploiting predictable elements in German message openings such as “Heil Hitler.”
• Secrecy and Aftermath: Turing is not publicly acknowledged or thanked for his enormous contributions due to the work’s classified nature.

Notable Exchange:

• Robert Krulwich: “If I were King George, I would sent him a little.”
• Jana Levin: “He didn’t.” (13:03)

---

5. Artificial Intelligence and the Turing Test (13:05–16:43)

• Return to Theoretical Work: Back at Manchester University, Turing shepherds the first programmable computers but is already thinking further: could a machine think?
  • Jana Levin: “He really invented the field of artificial intelligence and was the first person to hypothesize about whether a machine could actually be said to think.” (13:44)
• Turing Test:
  • James Gleick: “Get a person, sit him down at a computer, have him start a conversation in text…” (14:33)
    If a machine's replies are indistinguishable from a human's, it passes the test.
• Philosophical Objections:
  • Jana Levin (quoting Sir Geoffrey Jefferson): “No machine will ever think like a human, because no machine can feel like we do, and in all the ways we do... be warmed by flattery, be charmed by sex, be angry...” (15:23)
  • Turing responds, essentially, by noting that we never truly know if another human is sentient—we only infer it.
• Provocative Conclusion: Turing extends the parallel between mind & machine:
  • David Levitt: “It’s not just that I want to build a machine that can think. It’s that we are mach[ines], that think.” (15:57)
  • Jad Abumrad: “We are just machines ourselves, just soulless biological machines.” (16:06)

---

6. Persecution and Suicide (16:43–19:20)

• Victimhood and Empathy: Turing identifies not just with outsider humans, but with future persecuted machines; the show draws a parallel between Turing's ostracism and the imagined plight of thinking machines.
  • Jana Levin: “For Turing, the machines were more likely to be victims, victims of prejudice...” (16:43)
• Chemical Castration: The court sentences Turing to hormone therapy intended as a ‘cure’.
  • Jana Levin: “The cure consisted of massive doses of estrogen.” (17:21)
  • David Levitt: “What it really did was it made him impotent and profoundly depressed. He grows breasts... He’s still vocally gay.” (18:03)
• Turing’s Fears: He worries that bias against his sexuality will cause his scientific theories to be dismissed.
  • Jana Levin (quoting Turing’s letter):
    “I'm rather afraid that the following syllogism may be used by some in the future. Turing believes machines think. Turing lies with men, therefore machines do not think. Yours in distress, Alan.” (18:25)
• Final Days and Suicide:
  • Turing, depressed and ostracized, dies by cyanide-laced apple in 1954, echoing the “poison apple” from his favorite film, Snow White.

---

7. Legacy, Apology, and Open Questions (19:20–23:31)

• Delayed Recognition: Prime Minister Gordon Brown issues a formal apology in 2009; a public campaign for Turing’s posthumous pardon fails in 2012.
• Enduring Resonance:
  • Robert Krulwich: “It’s an amazing life, and I’m in awe that anybody could have accomplished quite as much as he did and suffered as much as he did...”
• Are We Just Machines? The episode closes by returning to Turing’s philosophical challenge. The hosts debate whether accepting ourselves as machines is inspiring or dispiriting.
  • Jad Abumrad:
    “I think we're just machines, and I think we're just made of matter. I'm sorry to be giving religious opinions here, because these are religious opinions, but for me that doesn't make me feel that we're any less special.” (21:17)
  • Robert Krulwich:
    “If I built you a computer that could create equally beautiful watercolors and equally beautiful musical compositions, would you feel happier or diminished?” (21:59)
  • Jad Abumrad:
    “I feel the art I love is always art that I don't fully understand. There's some mystery there, always... And when the machine produces music that is as lovely as the music you and I love, I believe it will still be unfathomable.” (22:15–23:31)

---

Memorable Quotes

• Jad Abumrad (on Turing’s abstraction):
  “Turing’s machine is Cézanne’s watercolors. It’s Bach’s Prelude. He was a lonely 22 year old just thinking and he invented a thing that lives in the minds of every computer scientist today.” (09:18)

• Jana Levin (on empathy for machines):
  “For Turing, the machines were more likely to be victims, victims of prejudice, victims of injustice, victims of people like Jefferson... England was saying to Turing, you can't be what you are and we're going to change you.” (16:43)

• Turing’s own fear in a letter:
  “Turing believes machines think. Turing lies with men, therefore machines do not think. Yours in distress, Alan.” (18:25)

• Jad Abumrad (on mechanical humanity):
  “We are nothing more than flesh, blood, neurons. We are just machines ourselves, just soulless biological machines.” (16:06)

---

Timeline of Key Segments

• 01:44–03:31: Turing’s arrest and chemical castration
• 03:31–06:07: School years, Christopher Morcom, loss of faith
• 06:07–09:18: Turing machine explained and its revolutionary impact
• 09:51–13:05: WWII, Enigma codebreaking, the Bombe, Bletchley Park
• 13:05–16:43: Artificial Intelligence, the Turing Test, philosophy of the mind
• 16:43–19:20: Persecution, hormone therapy, Turing’s suicide
• 19:20–23:31: Apology, ongoing debate on mind-machines

---

Guest Attributions

• Jana Levin: Novelist and physicist, provides context about Turing’s work and personality.
• David Levitt: Biographer, gives detail on Turing’s personal life and emotional struggles.
• James Gleick: Science writer, explains the Turing machine and the Turing Test.
• Jad Abumrad: Co-host, frames the philosophical implications and emotional resonance.

---

Conclusion

This deeply evocative episode describes both the genius and tragedy of Alan Turing’s life. Through biography, invention, war, and philosophy, the story is at once an elegy and a challenge: what does it mean to think, to be human, to be a machine? As the hosts and guests highlight, Turing’s insights and misfortunes are inseparable from the enduring mysteries and controversies at the heart of science, technology, and society.

Transcript

[Commercial Announcer 1]

Your new home is now ready. Dr. Horton, America's builder has new homes that are ready today with new construction communities in Ellensburg and throughout the Greater Seattle area. Dr. Horton has the right home for you. At Dr. Horton, we're still building with flexible living spaces, smart home technology and two and three car garages. More communities and more homes available every day. Find your new home in ellensburg now ready at Dr. Horton.com Dr. Horton, America's builder and equal housing opportunity builder for delicious meals, you could go out to eat, or you could just make a Marie Callender's meal. Marie Callender's classic chicken parmigiano bowl is so good. It has marinara sauce that's made from scratch and creamy mozzarella cheese over pasta. It's delicious with no artificial flavors, colors or preservatives. And 30 grams of protein. You can find it in the frozen aisle. Marie Callender's what having it all tastes like.

[Commercial Announcer 2]

It's never too early for Lowe's Black Friday deals. Snag some of our biggest savings of the season right now, like 20 off select pre lit artificial Christmas trees and get yourself free. Select Dewalt cobalt or Craftsman tools when you buy a select battery or combo kit before the Black Friday rush. Because everyone loves free stuff, right? Lowe's we help you save valid through 123 while supplies last. Selection varies by location.

[Jad Abumrad]

Wait, you're listening.

[David Levitt]

Okay.

[Jad Abumrad]

All right.

[David Levitt]

Okay.

[Jad Abumrad]

All right. You're listening to Radiolab Radio.

[Robert Krulwich]

From WNYC.

[David Levitt]

And npr.

[Robert Krulwich]

Hey there. I'm Robert Krulwich. JAD is on paternity leave. This is Radiolab, the podcast, and today I thought I'd introduce you to a particular guy on a particular day in Manchester, England. It's 1952, and Alan Turing, a math professor, discovers that a number of things have disappeared from his home. Looked kind of like a burglary. He was missing a shirt, a pair.

[David Levitt]

Of shoes, an old pair of pants, maybe a compass.

[Jana Levin]

It was stuff. It was just household stuff. Nothing of anything of value.

[Robert Krulwich]

That's Jana Levin and David Levitt. Both of them have written books about Alan Turing.

[Jana Levin]

And so being very literal minded, he thought, well, what do you do when you're robbed? You call the police.

[David Levitt]

So the police come to his house, the detectives, he has this conversation and they say, you know, he's kind of a curious chap. They let him talk and they're like, it's a real shame. We're going to have to arrest him.

[Robert Krulwich]

Who?

[David Levitt]

Turing?

[Robert Krulwich]

Why would they have to arrest. They're just coming to.

[David Levitt]

Because he's effectively implicated himself in terms.

[Robert Krulwich]

Here's what happened. The police sat turing down and said, who do you think made off with those things of yours? And he says to them he suspected.

[Jana Levin]

The thief was an acquaintance of his boyfriend.

[Robert Krulwich]

His boyfriend?

[Jana Levin]

Yes. Yes.

[Robert Krulwich]

See, at the time, there was a.

[Jana Levin]

Law in England which criminalized, quote unquote, acts of gross indecency between adult men in public or private.

[Robert Krulwich]

So he told the cops that he was having sex with a guy. Was that why we.

[David Levitt]

He doesn't exactly say we're having sex, but he says enough that it's clear he was never ashamed of being gay. This is just not something, again, that he understood what the fuss was about.

[Robert Krulwich]

So what happened to him? Was he. Was he convicted?

[David Levitt]

Yeah, he's convicted and he's.

[Robert Krulwich]

What's his sentence?

[David Levitt]

Estrogen pills and implants. Estrogen implants.

[Robert Krulwich]

Oh, my God.

[David Levitt]

Yeah. Chemical castration.

[Robert Krulwich]

And when I learned this, I wondered if those policemen had any idea that the guy they were arresting was, first of all, one of the great minds of the 20th century, a war hero who single handedly, almost by himself, shortened World War II by at least two years. And the questions he posed way back then are still, I think, the most provocative ideas I know. But we're getting a little ahead of ourselves. So let me back up to when he was a schoolboy, around 15 or 16, in England.

[Jana Levin]

He gets to Sherborne School, which is the public school, as they say in England.

[David Levitt]

I guess we would call it a boarding school. Boarding school for boys. Where.

[Robert Krulwich]

What did he look like?

[David Levitt]

He had dark hair, very dark hair, sort of square face. He wasn't unattractive, he was just so goofy.

[Robert Krulwich]

So did the other kids make fun of him at school or did he?

[David Levitt]

Yeah, I mean, he's teased, taunted, bullied, but he's not completely unhappy.

[Jana Levin]

He falls in love with another student.

[David Levitt]

Named Christopher Morcom, who's very charming, very socially smooth, handsome. They have this bond over science. It's an unrequited love.

[Robert Krulwich]

Did he express his love to this other kid or.

[David Levitt]

I think it was pretty obvious. He was always sort of there, sitting next to Chris Morcom, every class, right behind him, right next to him. And I think at some point Chris commented that, you know, maybe it's a little too much attention, but I don't think he really made a formal declaration of his love. But he did maintain a relationship with Chris mother, even after Chris died. Chris Morecambe died while he was still in school of Bavarian tuberculosis and had kept his illness a secret. Just one day, there was just this announcement he was dead. So I think it came as a complete shock to Alan.

[Jana Levin]

His memory really lingered. And I think that.

[Robert Krulwich]

How do we know that a kid had a boy crush in school?

[Jana Levin]

There are letters. Most moving are the letters that he wrote after Morcam's death.

[Robert Krulwich]

We actually went out and found a few of them, and here's one that he wrote to his mother. He says, I feel sure that I shall meet Morecambe again somewhere, and there will be some work for us to do together, as I believe there was for us to do here, now that I'm left asleep.

[David Levitt]

He wanted to believe that Chris's spirit lived on, and he was sort of awkwardly trying on these ideas that he had inherited from his religious upbringing.

[Robert Krulwich]

But, and you can see this in.

[David Levitt]

The letters, too, Turing begins to lose his faith and eventually comes to this sort of brutal conclusion that when Chris was gone, he was gone.

[Robert Krulwich]

The only love he had left at that point was mathematics. So he goes off to King's College, Cambridge, to study math.

[Jana Levin]

Yeah, exactly.

[Robert Krulwich]

He was still kind of a loner.

[Jana Levin]

If you look at photographs of Turing, I think I'm always struck by the fact that he looks like he's not actually there. He looks like he's like a lot of mathematicians. He lives simultaneously in two different worlds, the world that the rest of us live in. And he lived in a kind of extraordinary world of abstraction.

[David Levitt]

You know, lying in the fields in Cambridge, just him and his thoughts staring.

[Robert Krulwich]

Up at the sky.

[David Levitt]

He did do that. He would literally go and lie in the meadow and he would have these epiphanies, these realizations.

[Robert Krulwich]

And one day he's lying in Grantchester Meadows, that's near the campus, and he's thinking over a pretty tough problem. Is there a quick, automatic way to prove or disprove a mathematical proposition? This was a big question in math at the time, the ins and outs of which aren't all that important to us. What's important is that it led to Alan Turing's idea for, of all things, a machine.

[Jad Abumrad]

The machine doesn't exist. The machine is never built. It is never meant to be built.

[Robert Krulwich]

This is James Glick, a science writer who has studied Turing.

[Jad Abumrad]

It's the world's most impractical machine, but it's very simple. These were the elements of the machine. Number one, piece of tape, infinitely long. So therefore, it's already never going to exist because we can't have infinitely long pieces of tape.

[Robert Krulwich]

And number two, something that reads or writes ones and zeros on the Tape and number three, a set of instructions.

[Jad Abumrad]

So if you've got a zero, then you go to the left and you write a one, or if you've got a one, go to the left and you write another one. And you got to remember where you've been so you have a certain amount of memory, but that's it. And then he proved that the machine could do anything.

[Robert Krulwich]

You could add, of course, and then you could subtract and multiply. You could also do a little calculus, actually a lot of calculus. You could do trig and mathematical proofs and sophisticated mathematical proofs.

[Jad Abumrad]

Anything that could be done in mathematics mechanically could be done by his imaginary idiot simple machine.

[Robert Krulwich]

Is this such a big idea? I mean, all you're saying really is he figured out how to put logic or actually how to program a machine.

[Jad Abumrad]

Okay, but, but no, Robert, you're already cheating because as soon as you say you're going to give the machine some logic and then as soon as you use the word program, you're using very modern bits of knowledge that we've all internalized. But the idea of putting logic into a machine, no one thought of that. That's just weird.

[Jana Levin]

Machines at that time bear in mind were generally single function.

[David Levitt]

The idea that you do your email on your computer and Photoshop, you know, you don't buy a different machine. That is ingenious. That traces back to Turing's original idea that I can build an electromechanical brain and I can teach it how to do different things.

[Robert Krulwich]

This was the dawn of the computer age.

[David Levitt]

Computer used to mean a person, usually.

[Jana Levin]

A woman, who would sit and do mathematics.

[Robert Krulwich]

And now we got this guy who's saying that with a simple formula, tape, code and a set of instructions, we can give human like abilities to a machine. And not just the abilities of our hands, but the nimble ability of our beautiful brains.

[Jad Abumrad]

It's a beautiful, magical, simple idea. Turing's machine is Cezanne's watercolors. It's Bach's Prelude. He was a lonely 22 year old just thinking and he invented a thing that lives in the minds of every computer scientist today. He didn't realize that just a few years later he was going to be applying these same skills to winning the war for England.

[Robert Krulwich]

The Battle of London, which began with strong forces of Nazi bombers attacking the capital at night, led to a big fire on the Waterside. It's 1940 and the German high command is sending secret messages written in code to naval commanders, to U boat captains saying our sink that ship. Mine. This Harbor. The messages were encrypted in this crazy fangled encrypting thing that they called the.

[David Levitt]

Enigma machine, kind of a typewriter.

[Robert Krulwich]

So they would type bomb that boat in German, of course, and the machine would swap the letters and turn the type into gibberish.

[David Levitt]

But they changed the settings, every transmission. And what this meant was that it was considered by both the Germans and the British to be uncrackable.

[Robert Krulwich]

Except Winston Churchill thought, ah, let me try. So in total secrecy, British intelligence brought together the most talented amateur decoders that they could find.

[Jana Levin]

They chose mathematicians, chess champions, people who could solve the Sunday Times cross puzzle extremely fast.

[Robert Krulwich]

And they were all instructed to go to a set of buildings halfway between Oxford and Cambridge. It was a place called Bletchley Park.

[Jana Levin]

But the architect of the effort was really Alan Turing, who was an odd.

[Robert Krulwich]

Kind of choice because in many ways he was a very strange man.

[Jana Levin]

He was kind of paranoid. I think that was clear. I mean, he had this system where his bicycle chain came off every certain number of revolutions, and he knew how many revolutions he was able to ride before the chain would come off. And it was, I think, in order to stop other people from riding his bicycle. But he was the one who, again, had a very typically Turing ish sort of breakthrough. He thought, well, this code is generated by a machine. Therefore a machine can be built that will be able to break the code. So he built this machine that was called the bomb, and it was a.

[Robert Krulwich]

And it was huge. It was the size of a wall. And it could try out all kinds of different solutions to this breaking the code. And Turing decided to focus this machine on one little Achilles heel that he found in the coat itself. At the beginning of a typical message, a German would get on the machine.

[David Levitt]

And he'd have sort of habitual openings.

[Jana Levin]

You know, phrases that were very, very commonly used. And the Germans were fairly unimaginative, unimaginative.

[Robert Krulwich]

At the start, like, you know, heil Hitler or good morning or something like that.

[Jana Levin]

Exactly.

[David Levitt]

Heil Hitler. Or the weather.

[Robert Krulwich]

So, Heil would be H E I L, right?

[David Levitt]

Yeah.

[Robert Krulwich]

There's your in.

[David Levitt]

And then they realized that they could actually crack the code because of this, I would say, mystic.

[Robert Krulwich]

Throughout the world, throngs of people hail.

[Jad Abumrad]

The end of the war in Europe.

[Robert Krulwich]

When the English realized that Alan Turing and his team had broken the code, did that make Alan Turing into a superstar? I mean, did he get birthday greetings from the Queen?

[Jana Levin]

Not at all, because it was all top secret.

[Robert Krulwich]

Well, does that mean that King George didn't know of Alan Turing or Winston Churchill? Didn't know.

[Jana Levin]

Churchill certainly knew.

[David Levitt]

Churchill definitely took a particular interest in Turing and Turing's transmissions.

[Robert Krulwich]

Oh, he did, sure.

[David Levitt]

He's a war hero, there's no question about that. His contribution is of crucial importance in terms of turning the tide of the war in favor of the Allies.

[Jana Levin]

And yet, as far as I'm aware, Turing was never thanked or acknowledged for what he did.

[Robert Krulwich]

If I were King George, I would sent him a little.

[Jana Levin]

He didn't.

[Robert Krulwich]

Having defeated the Enigma machine, Turing now goes back to his first love, the Turing machine. Mathematicians all over the world are now building computers and big refrigerator sized contraptions. Actually, there was one at Manchester University where Turing took a teaching job. And the one there did a lot more than just math.

[Jana Levin]

And the machine could do all sorts of things. I believe it could sing. I'm pretty sure it could sing God Save the King. Really not very well.

[Robert Krulwich]

This is what it actually sounded like. It's not something you really want to march to.

[Jana Levin]

It was not the machine that Turing ideally would have liked to build.

[Robert Krulwich]

Turing had a bigger idea at this.

[Jana Levin]

Point, the idea of the thinking machine. He really invented the field of artificial intelligence and was the first person to hypothesize about whether a machine could actually be said to think.

[Robert Krulwich]

And not just think, thought Turing, but maybe flirt with you a little bit or joke with you. To have a sentience inside an electronic manufactured mind.

[David Levitt]

When people said, how would you know that mind was truly sentient? He said, just ask it. Just ask it.

[James Glick]

Are you truly sentient?

[Jad Abumrad]

Yes.

[Robert Krulwich]

Well, it's not going to be ever that easy. But Turing did come up with a test. It's a way to test whether a machine is doing something like thinking, like human thinking.

[Jad Abumrad]

What we now call the Turing Test.

[Robert Krulwich]

We've described it on our show before. This is from the show we called Talking to Machines.

[James Glick]

Get a person, sit him down at a computer, have him start a conversation in text. Hi, how are you? Enter good. Pops up on the screen. Sort of like Internet chat.

[Robert Krulwich]

Yep.

[James Glick]

So after that first conversation, have him do it again, and then again, you know, hi, hello, how are you? Et cetera, back and forth. But here's the catch. Half of these conversations will be with real people. Half will be with these computer programs that are basically impersonating people.

[David Levitt]

If you can put this thing behind a curtain and you talk to it and it convinces you that it's intelligent and alive and sentient, then it is. What's the big fuss?

[Robert Krulwich]

But there was a big fuss. Hold on. One Second, a neuroscientist at the time, Sir Geoffrey Jefferson, turned to Turing and said, how dare you? No machine will ever think like a human, because no machine can feel like we do, and in all the ways we do.

[Jana Levin]

Pleasure at its success, grief when its valves fuse, be warmed by flattery, be made miserable by its mistakes, be charmed by sex, be angry or miserable when it cannot get what it wants. And Turing's response to that was, well, I can say the same thing to you. You know, I can say to you, Robert, I don't know what's going on inside your brain. You tell me what you're feeling and what you're experiencing, but how do I know that what you're. How do any of us know that any other human being is a human being?

[David Levitt]

Turing is really one of the first to say. He's the first to say it's not just that I want to build a machine that can think. It's that we are Mach, that think.

[Jad Abumrad]

We are nothing more than flesh, blood, neurons. We are just machines ourselves, just soulless biological machines.

[David Levitt]

And this isn't a dark moment for him.

[Robert Krulwich]

It's a moment of acceptance, says Jana. But this time, it's not about math or science. It's about something bigger. It's about the nature of the universe and our place in it. And according to David, not only did Turing feel like he himself was quite kind of a machine, he felt a kinship with all the thinking machines that would ever be manufactured in the future, all those mechanical minds. He felt he had something in common with them.

[Jana Levin]

For Turing, the machines were more likely to be victims, victims of prejudice, victims of injustice, victims of people like Jefferson. Jefferson is saying to the machines, you don't think, because I say you don't think. And you know, England was saying to Turing, you can't be what you are and we're going to change you.

[Robert Krulwich]

Which brings us back to where we started this show. It is now 1952. Alan Turing has been convicted of gross indecency, a crime punishable by, as we told you, a jail term. Or the court can order you to take hormone injections.

[Jana Levin]

And he was given a choice. He could go to prison or he could be, quote, unquote, cured. And the cure consisted of massive doses of estrogen.

[Robert Krulwich]

Nobody importance went and said to the judge, here's a character reference, by the way. This guy won the world war that we just fought.

[Jana Levin]

Well, I suppose you could say that they were cutting him a break by not sending him to prison, by giving him this horrific, horrific alternative.

[Robert Krulwich]

What were the hormones supposed to do?

[Jana Levin]

It was the crudest kind of pseudoscience. There was some claptrap theory that homosexuality could be cured through injections of estrogen. What it really did was it made.

[David Levitt]

Him impotent and profoundly depressed. He grows breasts. It certainly doesn't work to repress his homosexuality. He's still vocally gay.

[Robert Krulwich]

But he's also worried that because he's now famously gay, his court case being in the papers and all, that, everybody from now on will dismiss his ideas. Writing once to a friend, he said.

[Jana Levin]

I'm rather afraid that the following syllogism may be used by some in the future. Turing believes machines think. Turing lies with men, therefore machines do not think. It is signed yours in distress, Alan.

[Robert Krulwich]

The hormone treatments ended. He kept working, but his mood darkened.

[Jana Levin]

Turing's favorite film was Snow White and the Seven Dwarves. And he particularly loved the scene where the witch dips the apple in the brew. And she chants, dip the apple in the brew. Let the sleeping death seep through.

[Robert Krulwich]

One night in 1954, it was June 8, he was at home. And at some point during that night, he kills himself. How?

[David Levitt]

He laces an apple with cyanide and he bites from the poison apple.

[Robert Krulwich]

He left no note. 55 years later, in 2009, the Prime Minister of Great Britain, Gordon Brown, issued a formal apology to Alan turing. And in 2011, coming up on his 100th birthday, 23,000 people sent a petition to the British government asking that Alan Turing be given a posthumous pardon for the so called crime of moral turpitude. In 2012, a government minister, Lord Tom McNally, said, no, that we will not do. Here's the A posthumous pardon was not considered appropriate as Alan Turing was properly convicted of what was at the time a criminal offense. He would have known that his offense was against the law and that he would be prosecuted. It's an amazing life and I'm in awe that anybody could have accomplished quite as much as he did and suffered as much as he did. It's almost overwhelming, but when I think about it, there's a piece of what Alan Turing thought up that just hurts a little, at least me. This idea that machines can one day become, in effect, our equivalent.

[Jad Abumrad]

This is still such a powerful and emotional question for us to deal with. And I guess we're still divided between people who think that would be kind of a cool thing and people who think that would be a horrible thing. And the people who think it would be a horrible thing, I guess feel that way partly because it makes us Feel kind of bad about ourselves. You know, we. Because we aren't. We aren't. There's nothing magical about us. If we're just machines.

[Robert Krulwich]

You fall on one side, but I fall on one side of these lines.

[Jad Abumrad]

No, I think what I'm willing to say is I think we're just machines, and I think we're just made of matter. I'm sorry to be giving religious opinions here, because these are religious opinions, but for me, that doesn't make me feel that we're any less special. I think, what a wonderful thing that a collection of matter created by a process of evolution that lasted billions of years. How wonderful that this process and that these little collections of matter are able to produce Cezanne's watercolors and Bach's Preludes. But I can live with that.

[Robert Krulwich]

Could you? If I built you a computer that could create equally beautiful watercolors and equally beautiful musical compositions, would you feel happier or diminished?

[Jad Abumrad]

I think in a way you're asking if you see how the trick is done, does it then vanish? Does it just become a trick? The trick being a great painting or a great piece of music? I feel the art I love is always art that I don't fully understand. There's some mystery there, always. I don't quite fathom it now. So if the computer is churning out a bunch of notes and you know exactly what the rules are that the computer is following, and there's no mystery, how can that possibly be a great piece of music? And the answer is, we don't know how the computer is going to do it. We don't know how the machine is going to do it. And when the machine produces music that is as lovely as the music that you and I love, I believe it will still be unfathomable.

[Robert Krulwich]

James Glick is the author of the Information. It's a book about information theory and artificial intelligence. David Levitt has a book called the man who Knew Too Much. It's a biography of Alan Turing. And Jana Levin has a novel about Turing. And Kurt Goodell, another mathematician, she calls her novel. And it's quite something, too, actually. It's got a lot of. Well, anyway, it's called A Madman Dreams of Turing Machines. Jad will be back soon. I'm Robert Krulwich. This is Radiolab.

[Jad Abumrad]

Hey, Radiolab. This is Billy Davenport and Lila Davenport. We're listeners from Knoxville, Tennessee.

[Sponsor Announcer]

Radiolab is supported in part by the.

[Jad Abumrad]

National Science foundation and by the Alfred P. Sloan Foundation. Enhancing public understanding of science and technology in the modern world more information about [e-mail]. thank you, Radiolab. End of message.

[Sponsor Announcer]

When you think about meal kit companies, what do you see? Probably long, complicated recipes and subscriptions you can't escape. But with the new Blue Apron, we're doing meal delivery differently. No subscription needed, faster, easier meals, and the same dedication to quality we've always had. Shop 100/[e-mail] Get 50% off your first two orders with code APRON50. Terms and conditions apply. Visit blueapron.com terms for more. NYC now delivers breaking news, top headlines, and in depth coverage from WNYC and Gothamist every morning, midday and evening. By sponsoring our programming, you'll reach a community of passionate listeners in an uncluttered audio experience. Visit sponsorship wnyc. Org to learn more.