The Rest Is Science

How Many Words Do You ACTUALLY Know?

52 min
Jun 10, 2026about 1 month ago
Listen to Episode
Summary

Hannah Fry and Michael Stevens explore vocabulary size through VocabOwl, a user-created website that estimates how many words people know. They discuss the gap between the 171,476 words in the Oxford English Dictionary and the 15,000-35,000 words most people actually use, test their own vocabularies, and explore why humans have unique hair growth patterns and the nature of internal monologues.

Insights
  • Most people know only 9-20% of available English words, yet can communicate effectively with just 3,000 core words—suggesting vocabulary size is less important than commonly assumed
  • Internal cognition varies dramatically between individuals: some think in words, others in images, and some have no internal monologue at all, challenging assumptions about universal human consciousness
  • Externalizing thoughts through speech improves task performance and emotional regulation, suggesting talking to oneself is a legitimate cognitive tool rather than a sign of mental distress
  • Many human traits like long hair growth lack clear evolutionary explanations and may persist simply because they don't harm survival, not because they serve a specific purpose
  • Naming and verbalizing abstract concepts or anxieties reduces their psychological power, making them less intimidating and easier to manage
Trends
Growing scientific interest in individual differences in consciousness and cognition (internal monologue, visualization ability)Shift from viewing 'talking to yourself' as pathological to recognizing it as a normal, beneficial cognitive strategyIncreased focus on preventive medicine and early disease detection through historical data analysis and microbiome researchRecognition that evolutionary explanations for human traits are often incomplete or speculative, requiring humility in scientific claimsGamification of educational tools (vocabulary testing) to increase engagement and self-assessment
Topics
Vocabulary Size and Language AcquisitionInternal Monologue and ConsciousnessCognitive Differences in Visualization and ThoughtHuman Hair Growth and EvolutionSexual Selection in Human TraitsEmotional Regulation Through ExternalizationTask Performance and Self-TalkNuclear Radiation and Electromagnetic SpectrumMicrobiome and Cancer PreventionCervical Cancer Prevention Through VaccinationDNA Damage and Cancer GenomicsEvolutionary Biology and Trait PersistenceLanguage Learning EfficiencyConsciousness and Subjective ExperienceBehavioral Psychology and Self-Perception
Companies
Cancer Research UK
Primary sponsor providing detailed segments on cancer research, microbiome links to bowel cancer, and cervical cancer...
Indeed
Sponsor offering job placement services, featured in mid-roll advertisement about hiring quality candidates
Oxford English Dictionary
Referenced as authoritative source for the precise count of 171,476 words in current English use
People
Hannah Fry
Co-host discussing vocabulary testing, internal monologues, and human evolution with personal anecdotes about cogniti...
Michael Stevens
Co-host exploring vocabulary, consciousness, and cognitive differences; shares personal experience with external thou...
Jake
Created VocabOwl website that tests vocabulary size; inspired by previous Rest Is Science episode discussion
Lauren
Producer mentioned during vocabulary test discussion about the word 'unctuous'
Quotes
"Every single person is extremely weird. And we have been taught and sort of, society expected to hide our weirdnesses from each other. And I think let's not do that anymore."
Hannah FryEnd of episode
"With just the grammar and 3000 words. Like learn 10 words a day. You can do it in a year."
Hannah FryVocabulary discussion
"As soon as you name it and you've said it, it's just not scary anymore."
Michael StevensInternal monologue discussion
"The genes that build our cells make up only 2% of our DNA. And for years, that is what scientists focused on. They treated the rest, the ancient viruses and stuff, as junk."
Hannah FryCancer Research UK segment
"You are more microbe than human. The average human adult has about 30 trillion human cells, but about 38 trillion tiny bugs inside of them."
Hannah FryCancer Research UK segment
Full Transcript
Welcome to the rest of Science, I'm Hannah Fry. And I'm Michael Stevens. Today is an episode of Field Notes, where we have discovered something made by you. And not just all of you, but one of you, named Jake. I don't know the last name. I don't know the last name either. Didn't provide it. But what I will say is Jake is an absolute legend. Yeah, maybe Jake wants to be a little bit anonymous, but his website should not be anonymous. Absolutely not. Inspired by a discussion we had on a previous episode about how many words does a person know and how many words are there to know, he looked into it and made a website that tests how many words you know. It estimates the size of your vocabulary. It certainly does. That's what we're going to get into today. This episode is brought to you by Cancer Research UK. Here's something strange. More DNA contains more ancient viral fragments than genes. The genes that build our cells make up only 2% of our DNA. And for years, that is what scientists focused on. They treated the rest, the ancient viruses and stuff, as junk. But now we know that that hidden majority, sometimes called the dark genome, influences how our biology works and how diseases like cancer behave. It's a reminder that progress rarely comes as a single breakthrough. It builds gradually. Cancer Research UK plays a central role in that progress, supporting decades of research into over 200 types of cancer, work that's helped double survival in the UK over the past 50 years. For more information about Cancer Research UK, their research breakthroughs and how you can support them, visit cancerresearchuk.org. Okay, so the website is called vocabowl, which looks like vocab bowl, like Super Bowl. It's a little bit competitive. Vocable. It's vocable. It's very fun. And you and I have both done it. We don't know each other's scores. Normally you just go through and you're shown words and then you have a multiple choice challenge. Which of these four is the definition of this word? And you go on like that for what, like 100 words? Yeah, 100 words. Yeah. Because there's how many in total 170,000 or so words that you could potentially know that are considered part of the English language? Yes. Yes. I think Jake quotes the OED as saying there's something like 171,476. Oh, that's precise. I wrote it down. Words in current use, what the OED considers current use. But hold on though. If that number is so precise, can we not just make one up and then add one to it? We would have to get it into common use. Is Kulf in there? Kulf is not there yet. Hey. I haven't confirmed this, but I'm going to just guess. Let's make Kulf a thing. Kulf. We don't need more Kulf in here. It's Kulf in this room. It's extremely Kulf. There's a lot of Kulf in here. But the OED also estimates that most people only know between 15 and 35,000 words. Right. Right. We should say actually, if you want to do this test, you should probably do it now because we're going to be saying some of the words. That would be really fun. If you're in your car, it's okay. We're not going to spoil anything. Oh, we might because you might learn. What the words are going to be? Obviously, I don't want people to have to stop. If you can, go do your score. Pause, go take the little test. If you can't, just put your fingers in your ears. Take them off the steering wheel, over your ears. Yeah. Yeah. Yeah. So how should we do this? Should we share our scores? I want to share the ones I got wrong because they're cool words. My experience of this was you start off and he's got it so you do the core basics first. And I was doing those. Now I was like, hey, check me out. I am doing so good. It's very easy at first. I didn't know it would get harder. I was like, I know every word. Oh my gosh. But no, it goes from core basics to intermediate advanced expert and then grandmaster. And can I just say, once you get to the grandmaster words, the advantage goes to the kind of nerd who has read a lot of those books with titles like the scrum tubulous person's guide to perplex of flibby words. And I am a person who owns like five books like that. So it paid off a little bit. Yeah. But let's see. So who's going to go first? I think you've won. From between us two, I think you've won because you're an English lit major, right? That's true. I could belly write a sentence until I was 25. You know, I'm okay. You just don't burn a sentence. I'm okay. Do you think we should have more animosity between us? Would that make the show more interesting? I think it might. We just dogged at each other all the time. When we first joined, they were like, the producers were like, it is when you disagree. That's when the real magic happens. I think that we're looking at Alistair and Rory and thought we should mirror that. So maybe we should lay into each other a bit more. We could try, but it's always hard because so often with math and science, it's not like, no, the square root of four is two and a half. Like, how are we going to disagree? We can disagree on interpretations and which facts to weigh in which way. But I think we're similar in a lot of ways too. That's true. Bluntly, I just quite like you. So, you know, I don't think it would be. I might tease you in jest. Just rip you around the edges a little here and there. No, it's fine. Yeah. I like you too. However, let's compare our vocabs. According to Jake's vocab owl. Vocab owl. Okay. What are we saying? Do you want the number I got correct out of? No, I want the estimated number of words you know. Okay. 73,400. Don't look at me like that. What was yours? 72,250. Wow. Wow. Okay, congratulations. Congratulations to you. All right. Well, that's a lot of words. I felt you. So, you know a thousand more words than me, approximately. What are they? Who knows? Probably British ones like chim chim cherry and and. Jiminy cricket. Jiminy cricket. I know Jiminy cricket. I like that. I say that when I'm upset. Jiminy. I say Jiminy Christmas. I got 10 words wrong. I got nine wrong. Oh, but maybe we've got them wrong in different parts. I think that's what it is because the way the website estimates your vocabulary is by saying, okay, in the English language, there are this many words that are of intermediate difficulty or intermediately known. And if you only know two thirds of them, then you only know two thirds of those words. Of the wider corpus. So I missed more from lower down the chain. Yeah, you must have done. And fewer up at the top, but there's fewer to know at the top. So you have a larger vocabulary than me. Even though. But I think maybe I'm lopsided. I think I think you've been reading too many of the scrum diddly umptious. Yes. And not enough of the Dick and Jane. Jack and Jill went up the hill. Jack and Jill went up, went up the what? I don't know that one, but uh, Borbarygmus, I know that one. What, where did you get wrong? I'll tell you, can I tell you the first word I got wrong? Yeah. I was annoyed about this actually. Okay. Um, it was the word Zenith. Oh, meaning like the top? I thought it meant top, but apparently it means strongest point. Oh, well, strongest and top can be related, but you know, it kind of depends on the options that you're given. Absolutely. It's the pinnacle of something. Uh, I thought it was the highest point, but it means, apparently it means like the peak. So which, which option did you choose? Um, there wouldn't have been highest and strongest. No, I think I sort of mucked up a little bit. Yeah. Okay. Well, that's fair. I mean, that'll happen. Like I don't think any of the ones I got wrong were unfair. I'm a little bit embarrassed about one, but I got the first one I got wrong was Zephyr. Zephyr? Now I knew that Zephyr was a kind of wind, but I was given two options. It's either a violent storm wind or a soft, gentle breeze, but then they get quite crazy once you get to what they do get crazy because then this next one, I think I should have known Laconic. Laconic. Laconic. I said, oh, that means being lazy and slow, but no, it means using very few words. Yeah. Did you know that? I think I did know that. I bet you did. Laconic is a great one. It is a good word. Oh, the way she describes things is so Laconic. No wasted words. Just okay. Should I go through what I've missed or should we trade? I don't have a full list of them. I'll be honest with you. I found the test quite painful. I don't like getting things wrong. Yeah. Well, me neither. Well, actually, no, I did like getting them wrong. I mean, look at me. I've written them all down and I've put them into sentences and I'm like, I'm not going to get these wrong again. So I'll share my list. Yeah, go on. Okay. Legubrius. Legubrius. I got that one wrong. Now I've heard the word before. I decided that it means looking or sounding happy or gay, but it means looking or sounding sad and dismal. I think I got that one wrong as well. You know, oh, really? Hmm. Legubrius. So that's a sad way to be. Ah, his legubrius pose. It you can really tell in the way that you're saying it. When you say legubrius, it sounds like the children with their legubrius play. But no, legubrius play would be very sad. Yeah. Okay. Unxious. I got that one wrong. Well, can I just tell you this one? I also got this one wrong, but I actually got this one wrong, particularly because I was sitting next to producer Lauren, who was like, oh, it means delicious. Apparently not. It means excessively or irritatingly flattering. That is cool. I would not have guessed that. I guess that it meant dry and rough and rude. Unxious. Oh, this drink is unxious. But no, to be unxious means to be like, like a salesperson is unxious. They're like, oh, you have such great tastes and oh, this is, you know, what's good. And you're, you know, it's just, oh, stop being so flattering. I was a bit unxious earlier when I told you I liked you. You said it, not me. And now we all understand it. This one is the one that I wish I'd not missed. Intervate. Right. Intervate. It does not mean to cause someone to be filled with energy. It means the opposite. It means to cause someone to feel drained of energy. That's a tricky one. That is a tricky one. Because you would, I think quite a lot of these actually, you know, when you see the word, you roughly know what it's to do with. But as to whether it's in the positive direction or the negative direction is, is actually quite a difficult thing to remember. The words that, that obviously go in one direction or another, they're more common. It's these weird ones like innervate. Intervate, you would think it means like, oh yeah, you know, that speech really innervated the crowd. But that would be a bad thing for the speech to do because heat innervates you. Makes you more sluggish. It feels wrong. I guess, did you get noisome, right? I don't know. Noisome is a, do you know what noisome means? Not now, not now. You asked me without multiple choice, without multiple choice. My own room. It sounds like noisome might mean like noisy, but it actually means stinky, bad smell. But it's got the word noise in it. Anyway, I was really proud that I knew that one. Okay. Then what about this one? Zinzy, Zinzy, Zinnick. I don't think I got that one. You don't think you got, I get you. You would remember because this was a ridiculous one. Zinzy, Zinzy, Zinnick. Did you get the hippo, phobia? If I did, I got it right. The one about the fear of long words. Sesquipedalian also means really long words. Meh. But then yeah, like hippo, phobia. I don't know the word off the top of my head. But then when I saw it, I'm like, it's got to be one of those. Hilariously long words. What's the word for when something describes what it is? So like the word describing fear of long words is in itself an extremely long word. Yeah. I think that would be, uh, autological. Autological, yeah. The word describes itself. The thing is, I think there's also quite a big difference between seeing these words and being able to take a good stab at what their definition is. That's a skill in and of itself. And then the opposite, which is to be able to conjure these words from the depths of your mind and use them correctly in a sentence. Yeah. And there's a certain point where it's impressive that you can use them, but you still shouldn't because it just makes everyone feel lost and confused. Like if I started talking about, ah, yes, but as we all know, that requires math in the Zinzy, Zinzy, Zinnick variety, whatever. That, that's an old archaic way of saying the eighth power of a number. Okay. Before superscripts were used. It's the German spelling of the medieval Italian word, Senso, meaning squared. Zin, Zick. And so to the power of two, to the power of two, to the power of two is to the power of the eighth. That's why Zinzy, Zinzy, Zinnick meant to the eighth power. And yes, if you start using that word when you're describing to the eighth power, people are going to think you're a bit of a Zinzy Zinzy. No, you aren't. You aren't even describing things better or more richly, just archaically. Do you know one of my favorite things to do in the world is to just pick general words, completely innocuous words and use them as insults for children. So for example, you absolute Bing, you know, you absolute Bing Bing. Yeah. Ah, okay. It's like an automata. You know, or like, stop being a Plinky, you know, right? This kind of thing. But just like almost say them with the, the, the venom that you might deliver as well. I thought you meant words that were really common, like you absolute table. Oh, I mean, you can do that a bit as well. Plinky and Bing are kind of, they're kind of cute. They're kind of cuter. Well, you know, banana is like the standard one, right? Can you stop being a banana? And a banana, of course. Sure. Yeah. You absurd chair leg. You absolute democracy. I use nerd a lot as an insult because I am such a nerd. I just think that it's fair. I think it's fair. I'll be like, yo, what up nerds? Yeah. But like actually I'm the one here who's like, well, actually on page seven, 12 of the Lord of the Rings, Gandalf says this. You, you can't see steam. That's not steam that you're visibly seen. The, you know, like the fog that comes off of dry ice. Yeah. I'm always the first to say that's actually water. That's not carbon dioxide. The cold gas is causing water vapor in the air to condense into a cloud. So the white stuff that you see off of dry ice, that's water. Yeah. No, I think you're allowed to call other people. Okay. There's three more that I got wrong. We're going to just cover these quickly. Go on. Pogona trophy. Okay. That is not a trophy hunting sport. That is the growing of a beard. Yes. I got that one wrong. Eclipse. Yes. I think I've got that one wrong as well. But see, that's literally an archaic word. It's a way of saying called or by the name of, oh, yes, the lady Eclipse, Jessica. Come on. If someone said that, I would, I would not go, dang, you are so good of a communicator. I'd be like, what does Eclipse mean? Yeah. Finally, Eucalagon. Eucalagon means a neighbor whose house is on fire. Oh yeah. I got that one wrong as well. You know what? Actually, there's a lot of overlap in the ones that we got wrong. Yeah. I think maybe I got an extra one or two wrong like Zenith in the early, but hang on. This doesn't make sense. You must have got one of these right. Yeah. One of the late ones, right? Yeah. Yeah. For example, I don't know why you don't remember this, but the Zinzi, Zinzi, Zinnick. Maybe you just guessed right. I actually did this test 15 minutes ago. So it really is extraordinary that I can't remember. I did this like three weeks ago. So maybe the deal is that like so many new words have been invented since then. Possibly what it is. It changed the curve. So Eucalagon, that is another like ridiculous. It's a character from the Iliad whose house was burned at this one point and it became an eponym. For some reason, like in literature, authors have written things like, ah, but who is this Eucalagon? Meaning who is this neighbor of mine that is suffering? And that has, I've never needed to use that word. No, fair. Absolutely fair. Just looking at this, these stats that he has here on the website. Actually, the number of words in each category increases as you go up the difficulties of the category. So core basics, in terms of the frequency of words that people use in the English language, there are only actually around 3000 core basic words. 7000 intermediate words, 10,000 advanced words, and then it's 25,000 expert words he describes it, and then 40,000 obscure words. So the words, so the harder they get, the more obscure they get. Not only are they harder, useless commonly and so on, but also there's way more of them. There are way more of them. Do you have your actual final results page open? I do. We could compare. I wrote down how many I got right in each category. Okay, go for it. I was 20 for 20 in core basics, 20 for 20 in intermediate. I got 19. Oh, interesting. I was 18 for 20 with advanced. 17. I was 17 for 20 in expert. 17. And I was 16 for 20 in grandmaster. 17, baby. Okay. So because you knew one more grandmaster word than me, which might have been the Zinzi, Zinzi, Zinnik, that's my guess. It could be. That meant the algorithm estimated you to know a thousand more words. Not that I'm going to be stuck on this for the rest of my life, but that might be what happened. I think that's probably what happened. But anyway, Jake, thank you for creating that. And please, everyone out there, go check it out. There'll be a link in the description. I think there's also something quite positive in that, that if you want to learn a new language, I mean, the idea of learning 70,000 words, 170,000 words feels extremely intimidating. But actually you can get really quite far with just 3000 words. I mean, that's nothing. That's right. That's right. With just the grammar and 3000 words. Like learn 10 words a day. You can do it in a year. Yeah. I mean, you won't know how to put them together, but. Go try this out. Vocab owl and let us know in the comments what you got. And we're all going to compare and we're all going to support and love each other. We're going to. Bunch of you. I just don't want people to get all judgmental and think that they're better than each other. Okay. This is not about the value of you as a person. It's about it's about having fun. It's about the value of this podcast. It's about the value of this podcast. Yeah. At the bottom of the page, it doesn't even say the name. That's why I don't know Jake's full name. It's not made by Jake. Well, it's just inspired by the rest is science with Professor Hannah Fry and not Professor Michael Stevens. That part isn't there. The not professor, but whenever I see those together, I'm always like, oh, I don't get to have anything in front of my name. By Professor Hannah Fry and Mr. Michael Stevens. Anyway, coming up after the break, we're going to answer some of your questions. We certainly are. This segment is brought to you by Cancer Research UK. Now, most cancer stories begin at the moment of diagnosis, but today we're going to start much earlier before cancer has even had a chance to begin. You can think of it like a biological time machine. If you go back far enough, understand what's starting to change. You can help save lives and spare people from ever facing diagnosis, treatment, and what follows. And that is what Cancer Research UK scientists are exploring. How the ecosystem inside of us has changed over time and what that could reveal about a cancer's earliest roots. So today we are asking what if the key to preventing cancer is by decoding what is already inside of us. Here's a fact that you may already be aware of, Michael. You are more microbe than human. The average human adult has about 30 trillion human cells, but about 38 trillion tiny bugs inside of them. Most of them are in the gut microbiome. This biome, it's not just digesting your dinner. It can influence your immunity, it can influence your mood, it can influence how you think. In general, you have these sort of good bugs in inverted commas that help you to protect against toxins and that train the immune system to behave. And then you have some bad bugs that produce toxins that damage your cells, your bowel cells, and potentially can help tumors to grow. And normally in a healthy adult, you would have the good bugs out competing the bad bugs for resources and space. But as you get older, our microbiome can end up changing and the number of good bugs declines over time. And so can't crowd out those bad bugs. And some of the chemicals that were once beneficial to us would end up start behaving a little bit differently. Now, we call them bugs. And what are they? I mean, they're little micro organisms, bacteria. They have completely different DNA than us. They are not us. And yet they outnumber the cells you and I are made out of. If you wanted to count every single bacteria in your body, one every second, it would take you a million years. A lot of these bacteria are good, but harmful shifts in your gut microbiome can create the ideal environment for bowel cancer to develop and grow. But cancer research UK scientists are now screening a library of around 1500 approved drugs to see if any of them help stop the shift from helpful to harmful bacteria. But here's a question. So we know about the link between age and bowel cancer. But why is it becoming more common in young adults? OK, well, to try and answer that question, cancer research UK scientists are tapping into one of the world's oldest bowel cancer archives because hidden beneath this hospital, there is tens of thousands of bowel cancer samples that have been collected all the way back to the 1950s. Right. And what cancer research UK scientists have been doing has been hunting for essentially genomic scars, right? Little bits of DNA damage inside of the tumours, because different causes of cancer can end up leaving different scars in the DNA. And you can now use whole genome sequencing to map all of the DNA of all of those tumours. And then by comparing the different scars in the DNA in these tumours from the 1950s all the way through to now, scientists can investigate what are the environmental factors, right? Because essentially you can see in your DNA that the sum of everything your body experiences over a lifetime, right? Little lifestyle, your diet, your pollution, your stress and then how it ends up affecting your biology. And if those bad bug scars become more common over the decades, then that's a really strong clue that targeting these bad bugs specifically could help to prevent bowel cancer in younger people. So by using the past to protect our future, we can help to stop these harmful shifts before they even start. And that's how cancer research UK is creating a future where fewer people hear the words, you have cancer. In the past 50 years, their work has helped double cancer survival in the UK and saved and improved millions of lives around the world. And in the golden age of cancer research, we are finally unlocking the secrets of time to stop cancer before it can even begin. For more information about cancer research UK, their research, breakthroughs and how you can support them, visit cancerresearchuk.org forward slash rest is science. This episode is brought to you by cancer research UK. In the UK, nearly one in two people will face cancer in their lifetime. The question is, could science stop cancer before it begins? In over the past 50 years, cancer research UK has helped double cancer survival in the UK. And that's proof of what research can achieve, like take cervical cancer. Almost every case is caused by HPV, the human papillomavirus. And when scientists uncovered that, they were able to do it. Scientists uncovered that link, prevention became possible. Indeed, it did by a vaccine and it's protection that works way before the cancer itself can actually grow. After the vaccine was introduced, cervical cancer rates in England were nearly 90% lower than expected in women in their 20s. I mean, we're now genuinely at a point where this is a disease that is disappearing in young women in the UK. This is something that I really hope my daughters will never have to deal with. For more information about cancer research UK, their research, breakthroughs and how you can support them, visit cancerresearchuk.org forward slash rest is science. Indeed presents. Hires you can't afford to get wrong. Like a warehouse operations manager. Uh, where were the forklifts? I sold them. They were too expensive. I got a great deal on these scooters though. You expect us to move a two-ton pallet on a scooter. It'll be fun. Just think of the core strength you'll build. This is a job for sponsored jobs. This is what happens when you don't sponsor your job on Indeed. So the next time you need someone to get the job done right, get matched with quality candidates with an Indeed sponsored job. Visit Indeed.com slash Next hire and sponsor your job today. OK, we're back with a question from Andreas from Sweden who said, I recently listened to episodes about microwaves and fridges and I've heard that if you stand at the right distance from a nuclear blast, you get a perfectly microwave pizza. Is that really possible or is it just nonsense? For OK, I want to imagine that when I was listening to this, I was thinking of it very literally and it's like, if you stand just far enough away, you get a perfectly frozen pizza. Like it just falls out of the sky. There you go. A perfectly cooked pizza. You have to be holding the pizza to begin with, I think is what he means. I think it's being. And then it becomes cooked because of the blast. Right. Is that true? Uh, no. Oh. Is the short answer. Shoot. But the slightly longer answer is no, but in an interesting way. I think. OK, so the thing is, is that you get almost no microwaves from a nuclear. Oh, bummer. I would have assumed it'd be a lot. Yeah. It's got a lot of everything, every kind. All across the electromagnetic spectrum. But no. But what it is, is you get 5% that's gamma rays, neutrons, the sort of initial nuclear radiation. 35%. This is from the nuclear detonation. 35% is thermal radiation. So infrared, visible light, UV, the kind of great blast. 50% is kinetic energy in the shockwave. Oh, so half of it is just a pressure wave through matter, through the air, through, wow. And then 10% is residual radiation, the kind of fallout. And I mean, there's not that much microwaves in that list, right? So it's almost all this flash of infrared and visible light. But also flash is kind of the operative word there because it's not lasting long enough, you know? It's not sort of like you put your frozen pizza in the microwave. If that's how you cook them. Oh, yeah, right. Now I wouldn't do it that way. No, me neither. But fine. Who asked this question? I've got a lot of suspicions. Someone from Sweden. Oh, it all makes sense now. But yeah, it was right. You're not going to, you could put your pizza in the microwave and shoot microwaves at it for minutes and minutes. Right. A nuclear blast is going to ionize for years, but it's going to blast for a second. Few seconds, exactly maximum. It's like, but it doesn't cook in the same way. It won't cook in the same way. It's like it's more like you're standing next to the sun for a second. Yeah, right. Right. It's sort of the difference between warming yourself by the fire and warming yourself in the fire. Big difference. The sort of the fundamental difference of what's going on here. Also, I mean, the other thing is that the heat that is coming through isn't going to distinguish between the pizza and, you know, your face. Ah, true. Because I was just about to say, look, you could thaw the pizza. You could thaw the pizza. If you stood next to enough sequential atomic bomb explosions, just a blast of heat, another blast of heat, another blast of heat. Eventually it'll be room temperature. I would say overall an inefficient way to do it. Don't do it. Yeah. Yeah. Because you're you're getting cooked too. You are getting cooked too. Yeah. And if you'll, if you survive that bit, then the blast will come through immediately afterwards and knock you off your feet. So, so yeah, I'd go with no, generally. OK. Overall. OK. Next question. This one is for you. This is from Mark sat in a bar in Portugal and there's a lively discussion on why human needs their hair cut, but monkeys and apes don't. Yeah. This is one that I've I've asked a lot and we don't know the answer. The question is why are humans like the only primate that just kind of keeps growing hair only at a one one place, by the way. Now, would you call them orangutans or orangutans or orangutans? OK, so orangutans have pretty long hair. They do. Chimpanzees don't humans. The theory goes lost most of our hair because we needed to be able to sweat. We walk and move and especially run in ways that our tree dwelling ancestors didn't. And so it was it was really helpful to have less fur and more open skin so that we could cool down through through sweating. Cooling. But we needed protection on our heads because of ultraviolet light from the sun. But then for some reason, we not only kept fur hair on our heads, we also started growing it much longer, like the growing phase of each of our hair follicles on our heads is really long. It can be years. But for a pubic hair, it's like weeks. Yeah. For an eyelash hair, it's weeks, but like not many. Yeah, like six weeks. And that's and that's why the hairs are as long as they are. It's not that the body knows to stop growing after a certain length on my eyelash versus my head. Well, my head, it doesn't know what to do. But but the point is that they fall out of in Chile and new ones grow in and they only grow for a certain amount of time. But why it would be that humans would have longer hair than a lot of other primates is up to just guesses. It could have been sexual selection. It could have been that human populations around the world just liked it. They just thought it was pretty and they chose partners who were able to grow longer hair. It could have been a sign, maybe of health to them. We don't know. It could be about thermoregulation, though it doesn't quite make sense. Even the sexual selection guess doesn't really make sense because there are populations where people grow much longer hair than others. And there are papers where researchers have said, well, it's it's definitely sexual selection. It was up to us and our choices and who we made it with. And that's why. But those selections were different in different places. OK, so in like the tropics, there was still a preference for longer hair, but there were other things that were more important. And so that's why you'll have shorter hair here and longer hair there. But yeah, it's amazing how little we know. I mean, it could also be that there is no reason, you know, like evolution doesn't have a trajectory, it doesn't have a direction that it's heading for. Sometimes you just get features that appear for no reason at all. There is no pressure on it one way or the other. That's right. So either it it it helped in some way or it didn't help her hurt. And so it's just the way it is. Because I think the other thing that's worth saying is that actually the length of our hair is in part because we have the conditions in which to be able to take care of it, right? If you if you imagine instead of taking a modern human and making them wild in inverted commas, where they're kind of like moving around, you know, sleeping in different conditions, it's probable that the hair would break before it got to its full length. You know, yeah. So it could it could also just be there is no reason at all. Yeah. But it wasn't getting in the way. I for one, I'm glad it is there because. Look at that. It's my greatest feature. Haircare companies, sponsorship opportunities. Stonishing that they haven't already, frankly. I mean, look at this. I want to mean the hair lottery. Look at this. Hello. Between us, we average half a good head of hair. Between us, it's like one good head of hair. Because you've got like more than I've got less than I wouldn't consider myself negative. I meant, I meant on average, each person gets half. I was sharing. Oh, oh, oh, you were sharing. I was sharing. OK, OK. Fair enough. OK. I phrased it wrong. I appreciate it came across that way. OK. All right. Last question. This one from Megan, who asked, why do we talk to ourselves? Oh, this is good. OK, first off, you know, not everyone does. Yeah. Some people do not have an internal voice. I don't know if I believe them. Really? It's just it's very hard to define and talk about things like this. They don't have an internal voice. What does that mean to them? Because what does it mean to have an internal voice? I. When I silently think, it doesn't feel like it's a talking. Do you feel like it's words? Yeah, I get I'd words would be the best way to describe it. But they're not fully spoken. Oh, I think mine are. I talk out loud to myself a lot. That helps me to to figure out what I'm thinking and feeling. But in my own head, like, let me just try. Give me something. Give me like a something to a difficult puzzle. Yeah. OK. The only positive that sprang to mind is the last one you told me. Hold on. Let me let me get one. Let me get one. OK. I am an odd number. Take away a letter and I become even. What number am I? Eleven. I mean, that didn't involve very much. No, it didn't. But but here's what I'll say. It still gave me some insight into what's going on. It's very visual. There's one other. Oh, there's another answer. OK, so it's I'm an odd number. Take away a letter. Tune. No, stew. I don't know what is it? Seven. Shoot. Yeah. Of course, seven. OK, now tell me what happened in your mind. So what happened in my mind was very visual. It was more about images on white. While you were looking for a riddle, I was thinking about what did I eat? Typically for breakfast as a kid. And in my head, I wasn't thinking, well, usually I had this food. I just saw images of them. Interesting. What is it like in your head? Oh, she will not shut up. She is constantly trying. And it's verbal. It's verbal. It's verbal. The people who don't have this instantly. People who have the inability to to to visualize images in their mind. Yeah, I've heard about this. There's a sort of standard spectrum that you see, which is you imagine an apple. Imagine a juicy red apple in your head. And some people will see essentially a photorealistic version of this. That's what I got. Yeah. Is it? Oh, lucky thing. Like it's like I'm remembering a photo of an apple I saw once. OK. Like very, very with a lot of detail. Even before you ask for the detail, it's there. Like I'm noticing things that are there. I'm not looking for them and then confabulating them. Whereas for other people, myself included, it's much less like a fully formed picture. It's sort of like this maybe the feeling of the shape of an apple. Yeah, I know what that's like, too, though, because if you say, well, imagine an apple and a strawberry, I don't think too much about them. Sure. But if you really make me imagine an apple, I can get it all. Fully photorealistic, fully photorealistic. Oh, it's red and green and it's very ripe, you know. But I don't think I can quite get there. I don't know if I'm quite there. Imagine you had eight apples and you needed to share them with two people. I don't see eight photorealistic apples. I probably see like a half image, half word kind of thing, and that's all I need. So now this is the slight difference, actually, because if you... There was one program that I did where they put me in an MRI scanner and then asked me to do a number of mathematical calculations. Some of them were just simple arithmetic and some of them were about the movement of surfaces. Some of them were about some calculus, basically trying to solve these quite long, complicated equations. And over and over again, regardless of the problem that I was being given, the part of my brain that was lighting up was the visual cortex. Right. OK. So and that, I think, matches. It's not like a photorealistic version of what I'm manipulating, but it's definitely like the visual cortex is definitely doing a lot of work when it comes to mathematics, you're kind of manipulating things. But the people who are, who really struggle to create images in their minds, there's quite a big overlap with them and the ones who do not have an internal monologue whatsoever. Oh, is there? Yeah. So to not have an internal monologue, these people are still aware of the thoughts that they're having and they're just normal people from the outside. But they insist that what when they like debate something in their head, like, oh, should I should I take a break from studying right now? What do they? It just doesn't appear in the form of words. Right. I mean, I think I mean, I'm not I'm not one of these people, right? But but yeah, they say it appears in your head in the form of words. Yeah. For me, if I'm like, oh, should I take a break? I imagine what I could be doing during the break. I imagine the benefits I get from not taking a break as like experiences, like I feel them and I'm weighing them. I definitely aren't. The words break doesn't enter into it. Right. Oh, no. Until I take another step back, if I want to talk out loud about what I'm trying to decide, then it becomes very verbal. I think we should do a whole episode on this, you know, at some point, because I think it's really, really fascinating all of the different ways that you can test because it's incredibly difficult. I mean, this is this is like the hard problem of consciousness, right? It's like understanding the experience from somebody else's perspective. And and how difficult it is to describe your own internal world, your own internal monologue. Yeah, because I don't even know if I'm describing it the way I should be. It's hard. And I don't know if I should trust other people's descriptions of it. You know, I've always loved this hard problem of consciousness. What is it like to be someone else's mind? I just read a Greg Egan story where this couple wants to get closer. They just feel like they don't know why they got married. Like they don't really. So they just say, well, maybe we need to be closer. And through all these various steps, they eventually they realize that they cannot swap minds because as soon as they swap minds or bodies, they just learn what it's like to be in the other person's body, but not what it's like for them, for their conscious awareness. Right. So this this doctor has an idea. What if I take both of your memories and pull them together so you have each other's memories and then I'll knock you unconscious and I will put your brains into exactly the same physical mechanical shape. Your awareness is still there. And then when I snap my fingers, you won't be each other, but you will both be for a moment the same third person. And this makes them so close that they get divorced because they realize that not knowing the other person is exciting. And now that they're so close, they're like, this I don't I don't care for you anymore. And you may as well not be there because I already have myself. That's such a great idea. It's kind of cute. Yeah, I like that a lot. In terms of why we all do this, by the way, in terms of why we have this voice or where this voice comes from, if you and experiments have been done on this where you look at three four year old children, at that point, all of the voices are external for them. They are they're narrating everything they're doing. They're like, I'm going to put this block here and then I'm going to do this here. And then they're chattering all the time continually. And the idea is that essentially you just stop doing it out loud. It's the same voice that's going on, but you just do it in your head instead of doing it. Particularly out loud. But speaking out loud, by the way, I mean, so many people do this. It's way more people do it in private because it's associated with with something. There's something that people who've lost their minds. I know, I know. But people do it all the time. Like it's really difficult to find people who don't do this ever at all. And it's good. It's kind of good. It improves your performance on particular tasks. There's one of my favorite studies on this is from 2012, where they were asking people to find particular items in a supermarket. And those that were told to say the item's name out loud were much faster at finding others. Yeah, it makes me feel better because I talk out loud all the time. Even in the grocery store, I know that I can't. So I'll like mouth it. And if you look at me, I'm going. And I'm always afraid someone's going to like record me in public and be like, he's losing his mind. You're optimizing. I'm the old man muttering around the store being like under my breath going, well, would those be in the the the Thai food section or the potato chip section? I just want prawn crackers. Come on. I see I am doing that, but I'm doing it in my head. I think that I never gave it up as a kid. Right. I never internalized it. So I have to externalize it in order to form the word. But I'm always doing little shows and stuff, too. Like when I'm alone in my hotel room, I'll be like, ah, now when this I'll literally talk out loud, I'll be like, you know, I think that the warmer it's like I'm on the podcast, even when no one's listening. The warmer soda has has stronger flavors, but it's not as refreshing. And I think it's because of this. Do you really? Yeah. On your own. And that's I think is why I'm such a like a loner because I know that I can't do that around other people. I like that. So I have to escape. I work in my office by myself and I'm just sitting there basically performing a whole thing externalizing every single thought I have out loud with words. Can you do it in front of your wife? No, but I'm terrified that she'll walk in on me and I'll be doing this and she'll be like, you are not on camera. But I'm like this when I'm all alone. So you on camera is the most authentic version of you. The least authentic is this version. Wow. That must feel quite suffocating, then, where you need to continually talk in order to to process and think things. Yes, so I find myself. But you can't do it in your head. No, especially when I'm like traveling, visiting my wife's family and we're staying in their house and I never have a moment to myself. I'm like, I don't know what to do. I can't. I need to sit down and go, oh, why is Susan always saying that? I think it's because I need to just do that. And you say that to myself and it's embarrassing because it makes it look like I think that I've got an audience all the time. No. The first time I noticed this was weird is when I was on vacation with my family and they went down to the pool and I was going to go join them. And I just started talking out loud about why there was this sealed for your hygiene seal on the toilet. And I was like, out loud. I just said they do that so that people feel that the toilet is clean. And and I realized that no one was listening and that it wouldn't be an interesting thing to listen to. And yet. I was compelled to do it. See, see, I think I am having very, very, very similar conversations. But I'm just not doing it out loud. Well, good for you. Sometimes I'll be like narrating that. I mean, it's almost like there's two or more conversations going on simultaneously. So I might be like, oh, this hygiene thing, it's so that people blah, blah, blah, blah, blah. And then the other person will come in and be like, either good job or you're an idiot. That's sort of that goes on a lot. Oh, there's like a conversation. Oh, there's a conversation. And sometimes it can be this is the one that I find the most disconcerting. I'm I'm sure other people have this exact same experience, but I can be on stage and having giving an entire talk, right, a full presentation, especially if I know something reasonably well, and I can be verbally delivering the words and there will be an entire conversation going on in my head about something different. Do you like this other voice? She's really annoying. OK. But she's part of you and it like informs what you say out loud in this speech. She's called Colin. Where did this name Colin come from? She actually is called Colin. Well, maybe I'm giving away a bit too much for myself. Colin is the nasty part, you know? Yeah. Because I think it's just when when when when Colin is just like, for you're a bit much today, Colin, it feels very useful to externalize it. To externalize it, give it a name. I am definitely talking way too much. This reminds me of the Carl Jung thing about like as soon as the unconscious becomes conscious, it loses its power. And I think this is also a thing for another episode. But this is one of those silly reels from like the I'm a Navy SEAL teaching you how to be a man. But there was one that I thought was actually really, really insightful. And it was that to disarm someone who's who's got the upper hand, just mention how good they are. So like, if you're being interrogated, one way to disarm them and to kind of like make them second guess themselves is to actually say, you're really good at this interrogation. Like I can tell that you have been trained and have a lot of experience. Once it's spoken, now they have to live up to that. And he was like, if a guy comes up to you and shakes your hand like really firm, he's got power over you so long as you're going, oh gosh, OK. But if you go, wow, that was a really strong handshake. They say that that's what alpha men do. Then the guy's like, oh, oh, now I need to be an alpha. Yeah. And now it's out there and it's been named and it doesn't have power. It's not fate. If it's been said, right. And I think about that a lot beyond just the like strong handshake kind of a thing. But just in life, it's like as soon as you name it and you've said it, it's just not scary anymore. No, it's just not scary anymore. You know, also, speaking out loud, I mean, even just beyond naming the things that otherwise go unnamed, there is also some evidence that it does help with emotional regulation, that there is something really positive about this. So there's one study where they were like looking at people who had muttered to themselves, you've got this, Sarah, like you can do it, Claire. You know, as they were doing a task. Yeah, yeah, yeah. And they actually like it reduced their anxiety. It reduced their stress. You know, and I want to, I think that that's so true, but it can come in different flavors. All right. Like for someone like me, I don't think you got it, Michael. I externalize myself. This is very common, I think, like when I'm playing like basketball, you know, in the backyard, I'll be like, and look, look how well he does this. It's the announcer saying it. And then if it doesn't go in, I'm like, oh, we'll do that again. Now look at Michael never misses. Right. It's like a third person describing how good I am. But it does make me better. So I don't know who asked this original question. Megan. You've got a full episode. You've got a full, you basically got more of me and Michael there than, than I think either of us have ever given away on anything. But I think that ultimately, you know, the reason why I like talking about these kinds of things is because I think every single person is extremely weird. Every single person is extremely weird. And we have been taught and sort of, society expected to hide our weirdnesses from each other. And I think let's not do that anymore. Yeah. Yeah. Yeah. It doesn't help because it makes us think that other people like have just nothing weird about them, that they have no trouble waking up in the morning, that they love getting all their tasks done. And it's like, guys, it's called a task rather than having no name because it's terrible. Yeah. Yeah. We're all in the same boat. We're all in the same boat. You're weird, Michael. I'm weird. And so are you, our listeners. And every one of you. So stay weird and please, yeah, reach out to us. Jake, who else? We had Megan as well. Megan, guys, you are great role models for the rest of the audience. Send in your questions. The rest is science at goalhanger.com. Can't wait to hear from you. Or you can leave a comment under the video which you are watching now or the podcast which you have downloaded. We read all of them and we love your questions. So thank you. We'll see you next time. Bye-bye.