Probing Humanity’s Endless ‘Why?’
Humans are innately curious creatures. But have you ever wondered why?
Astrophysicist Mario Livio has. And now, he explores this question in a new book, “Why? What Makes Us Curious.”
“I chose this particular word, ‘why,’ because this particular question is uniquely human,” Livio says. “Other animals are curious, but only humans are worried and curious about reasons and causes for things. Only humans really ask the question, ‘Why?’”
Is curiosity something that we are born with? Definitely, Livio says.
“There are many studies that have shown that there is a strong genetic component to curiosity,” he notes. “It is also the case that some people are more curious than others, in the same way that some people have talent for music and others don’t or some people are smarter than others … But all people are curious, with the possible exception of people who are very deeply depressed or have certain kinds of brain damage.”
Humans exhibit two basic types of curiosity that show up in different parts of the brain during functional MRI scans.
One type has been dubbed “perceptual curiosity,” Livio says. This is what we feel when we see something that surprises or puzzles us or doesn’t match up with something we thought we knew. “It is felt as a sort of uneasiness, an unpleasant situation, a bit like an itch you need to scratch,” he explains.
A second kind has been dubbed “epistemic curiosity.” This is our love of knowledge, our desire to learn new things. “Our brain and our mind assigns value to this knowledge, so this is usually experienced as a pleasurable thing, with an anticipation of reward in the form of what we learn,” Livio says.
Kids are born scientists, Livio says. “Small children really want to understand cause and effect very early on. They somehow grasp that every effect is related to some cause and they want to understand those relations because that helps them to cope with their environment and to make fewer errors in their everyday lives.”
So, why does curiosity tend to diminish as we grow up?
“When we grow up, it’s not that we are not curious anymore, but our curiosity changes somewhat from the type that I call perceptual — which is being interested in many things and [having the ] willingness to even take risks for novelty — towards the epistemic curiosity, the love of knowledge,” Livio explains. “The love of knowledge stays with us throughout every time, all ages. Even when you are very old, people still are what somebody called ‘infovores’ — they want to devour information. [But] that willingness to take risks for novelty is definitely declining.”
Curiosity — in case you were wondering — has an evolutionary purpose: People had to be curious about what was happening around them or they wouldn’t survive. “People had to know, for example, what happens when you walk off a cliff because if you do that too often, it’s not going to have a good ending.”
“[But] the interesting thing, and one of the things that researchers still don’t have an answer to, is that we, as humans, seem to be much more curious than what is just necessary for survival,” Livio points out. Curiosity can also function as a coping mechanism. “Curiosity is the best remedy for fear,” he writes in his book.
“Very often we are afraid of things we don’t know much about or we don’t understand, and if we become curious about them and learn more about them, then we are much less afraid,” he explains.
In the age of Google, humans can satisfy one additional type of curiosity more easily than ever before: “specific curiosity.” This is when you need a particular piece of information, like the author of a book, for example.
The internet is, of course, fantastic for this and relieves us of that specific type of curiosity quickly, Livio says. Scientific research or big artistic projects, however, generally deal with questions for which humanity has not yet found an answer.
“Technology has allowed us to get rid of those immediate specific curiosity types of things, but it still allows us to continue to be epistemically very, very curious,” Livio says. “The only reason I ended up doing all this research on curiosity and writing this book is because I became extremely curious about curiosity and how it works.”
Mario Livio is an astrophysicist and author of several books, including Galileo: And the Science Deniers (Simon & Schuster, 2020). He’s based in Baltimore, Maryland.
IRA FLATOW: This is Science Friday. I’m Ira Flatow. Author Kurt Vonnegut famously wrote, “tigers got to hunt, birds got to fly, man’s got to sit and wonder why, why, why.” And, indeed, curiosity seems to be a fundamental part of what makes us tick. It’s certainly part of what drives scientists to investigate the fundamental nature of the universe and everything in it. We even named a Mars rover for curiosity.
But where does it come from? And do we all have the same kind, or amount, of curiosity? Are we really that much more curious than other animals? And what drives the inquisitive minds of people like Leonardo da Vinci, Richard Feynman, and others who can’t seem to stop asking questions about everything they encounter?
Astrophysicist Mario Livio is one of those kinds of folks, and he’s been wondering about these questions and more. And he’s written up his findings in a new book and he’s here to talk about it. Mario Livio is an astrophysicist and author of Why? What Makes Us Curious. Welcome back, Mario.
MARIO LIVIO: Thank you. Pleasure to be back.
IRA FLATOW: Nice to have you. We have an excerpt from your book on our website at sciencefriday.com/why. And let me just tell our listeners they can call in with questions about curiosity– 844-724-8255.
We’ll ask them, what do they think makes people– makes you, or people in general, curious? What makes you curious? 844-724-8255. 844-SCI-TALK. And of course you can always tweet us @scifri asking about– asking why about curiosity– a bit meta, isn’t it, Mario?
MARIO LIVIO: Yes. The main reason I chose this particular word, why, is because this particular question is uniquely human. Other animals are curious, but only humans are worried and curious about reasons and causes for things. Only humans really ask the question, why. So, that’s why I chose this as the title.
MARIO LIVIO: And in your book you focus on Leonardo da Vinci and Richard Feynman as examples of spectacular amounts of curiosity. What made you home in on those two?
MARIO LIVIO: Well, if you look at Leonardo da Vinci, I mean, I tried at first to determine, OK, what was he curious about. And basically, what I discovered was that he was curious about everything– I mean, with the possible exception of politics, which, he lived at the time of the Borgias, so anybody who was interested in politics got killed. So, it was very wise of him not to be curious about politics.
He got funded by the Borgias, but he was really curious about almost everything else– human anatomy, flow of water, all kinds of machines, of course painting and all that, all the arts, astronomy– you name it, he was curious about it.
IRA FLATOW: And Richard Feynman was well known for his curiosity and wrote books about it. I remember, he wrote a– or he’s been interviewed about talking about knowing. You know, I don’t understand why people don’t want to know things.
MARIO LIVIO: That’s right. He also once said that at the basis of all scientific research, there is this curiosity of you wanting to know why things happen. He also said, everything is interesting if you go into it deeply enough.
IRA FLATOW: Yeah. Is curiosity something that we are born with? Do you think some people are just more curious about stuff than others?
MARIO LIVIO: We definitely are born with it. I mean, there are many studies that have shown that there is a strong genetic component to curiosity. And it is also the case that some people are more curious than others, in the same way that some people have talent for music and others don’t, some people are smarter than others, things of that nature.
So yes, some people are curious than others. But all people are curious, with possible exception of people who are very, very deeply depressed or have certain kinds of brain damage.
MARIO LIVIO: So you can actually see curiosity at work in the brain.
MARIO LIVIO: Yes, you can. We couldn’t always. I mean, some time ago, we couldn’t do that. But today, you actually can take people and put them through functional MRI, which images the brain, and the images the brain while you make the people curious about something. So, while it doesn’t tell you everything– in fact, it tells you very little– it still does tell you which areas of the brain are activated when we are curious.
IRA FLATOW: Now, are there different kinds of curiosity that you can tell from the brain?
MARIO LIVIO: That’s right. So, there is a curiosity that has been dubbed perceptual curiosity, which is what we feel when we see something that surprises us, or puzzles us, or doesn’t quite agree with what we knew, things like that. And that is felt as sort of an uneasiness, an unpleasant situation, a bit like a scratch– an itch, sorry, you need to scratch.
On the other hand, there is what has been dubbed epistemic curiosity. That’s our love of knowledge, wanting to learn new things, where our brain and our mind assigns value to this knowledge. So, that is usually experienced as a pleasurable thing and with an anticipation of reward in the form of what we learn.
MARIO LIVIO: When you study curiosity in the brain, and you’re scanning people’s brains, what do you use to induce their curiosity?
MARIO LIVIO: So, people have used different methods. So, one– in order to induce perceptual curiosity, for example, that thing that you feel when you see something ambiguous, they have shown people blurred images of ordinary things, like blurred images of a bus, let’s say, and tried to make them guess what that is before showing them a clear image.
When you try to induce epistemic curiosity, this wanting to know things, they did that mostly by asking trivia questions, like, OK, which musical instrument was invented to sound a bit like a human voice, let’s say, which happens to be the violin, by the way. So, these different techniques to induce different types of curiosity.
MARIO LIVIO: I know you– Richard Feynman is one of my favorite historical figures in science. I’ve read a lot of his stuff, and one of the things he talks about is about being curious, and he has a debate with some of his artist friends. And I know in the book, you talk about his artist friends.
And he said there’s a difference between science and art, in that, as an artist, you may appreciate the color and texture of a flower, but as a scientist, not only can I appreciate the flower for its obvious looks, but I also can appreciate it for how it works, because I’ve studied that part of how it works. I’m curious about that side also. You wonder why– if you’re an artist, are you curious about that also?
MARIO LIVIO: So, well, Feynman brought this especially as a complaint, in some sense, against artists and writers who somehow, he felt, don’t appreciate enough the beauty in science and in the fact that you know something about this. He basically said, the fact that I know some things about how the flower works, and what the atoms do– that does not diminish my appreciation of the beauty of the colors. It only enhances it.
MARIO LIVIO: Let’s go to the phones, because lots of people want to talk about curiosity. Let’s take our first call from Bill in Winchester, Virginia. Hi, Bill.
BILL: Hey, thanks for taking my call. Way back in 1966, when I was a freshman majoring in chemistry, I had a brilliant chemistry professor. In his very first lecture, he talked about the word “why,” and how the word “why” has no place in science. “Why” was for philosophy and religion. Science was not about why, it was about how, H-O-W. What does your guest think?
MARIO LIVIO: I think that he’s right in a certain sense. The thing is that we almost, at this point, have sort of confused the two words when we discuss science. I mean, you say, OK, why is the universe expanding, or you can say, how is it expanding. And there is room for the two questions.
It is true that, much of the time, science deals with how.
IRA FLATOW: You know, if you’re a very curious person– and I know a lot of friends who are very curious– you have to put up with ridicule, sometimes. For example, I have a friend who’s obsessed with construction cranes, will stop at a construction site, and she’ll just look at the cranes working. And people who are with her will say, what are you looking at? And she says, I just like the cranes. I like to watch them work. You know, they– you’re nuts.
Don’t you agree that you– people are very curious about stuff. I know I like to stop on the side of the road and look at the rocks. You know, they’re just rocks. They’re not moving anywhere.
MARIO LIVIO: Yes, that’s true. But it is true that different people are curious about different things. There is no doubt about that, and there is nothing wrong with that. In fact, I would argue that you can always use the stuff that people are already curious about to actually drive them to other things that maybe you think are important for them to be curious about.
An example I like to give is that most children are curious about dinosaurs. They want to hear everything you can tell them about dinosaurs. But then you can tell them, aha, but dinosaurs also became extinct because of an asteroid that hit Earth. And then from that, you can get into the force of gravity, why did the asteroid hit Earth, things that maybe originally they were that curious about, but you made them curious about through the curiosity they already had.
IRA FLATOW: Well, that brings the age old question– and first, let me remind everybody, I’m talking with Mario Livio, author of Why? What Makes Us Curious– and that is, what happens to kids? As you say, they’re born sort of scientists. They’re curious and want to explore everything. What happens when they grow up?
MARIO LIVIO: So, what happens is the following. Small children are– they really want to understand cause and effect very early on. I mean, they somehow grasp that every effect is related to some cause, and they want to understand those relations, because that helps them really to cope with their environment and to make fewer errors in their everyday lives.
What happens is when we grow up– it’s not that we are not curious anymore, but our curiosity somewhat changes from the type that I called perceptual, or diversive, which is being interested in many things and willingness to take risks, even, for novelty, more towards the epistemic curiosity, the love of knowledge.
So, the love of knowledge stays with us, actually, throughout every time. I mean, all ages. I mean, even when you are very old, people still are what somebody called infovores– want to devour information. It is just that that willingness to take risks for novelty is definitely declining.
IRA FLATOW: Let’s go to Carmen in Clear Lake City, Texas. Hi, Carmen.
CARMEN: Hello. My question is, is there an evolutionary purpose to curiosity?
MARIO LIVIO: Yeah, absolutely. Of course there is. I mean, people had to be curious about what happens around them or they just wouldn’t know to survive. People also had to know what happens when you walk off a cliff, because if you do that too often, I mean, it’s not going to have a good ending.
IRA FLATOW: That’s self-selecting, that evolution.
MARIO LIVIO: Right. So, curiosity, for sure, evolved because of evolutionary pressure. The interesting thing, and one of the things that we still don’t even have– I mean, all the researchers still don’t have an answer to, is that we as humans seem to be much more curious than what is just necessary for survival.
Understanding quantum mechanics is very important for advances in physics, and one day surely becomes very, very applicable, but when it starts, it starts as a basic curiosity, and not one that has immediate applications. I mean, all science, at the end– I mean, I like this phrase, which says, there is applied research and not-yet-applied research. All research eventually becomes applied.
IRA FLATOW: Talking with Mario Livio, author of Why? What Makes Us Curious, on Science Friday from PRI, Public Radio International. Our number– 844-724-8255. Let’s go back to the phones, because people are curious. Hi. Let’s go to Megan in Alexandria, Virginia. Hi, welcome.
MEGAN: Hi. Thank you for taking my call. I just have two quick comments. One, I have insatiable curiosity, and I blame it on the fact that when I was born, lightning struck and my mom went into labor, and I came out asking what in the Sam Hill was that, you know. So, I have always been curious.
But really, when I was in college, I was studying to become a physicist, and I had to give that up because I was– I kept asking why and how is the math the way it is. So, curiosity became a detriment, in a way. But I understand the mechanics of physics, but the math just really got me.
IRA FLATOW: Mario, give her some advice.
MARIO LIVIO: Yes. I mean, unfortunately, not everybody is talented at mathematics in the same way that not everybody is talented in composing music like Mozart. I think that, to some extent, this is associated also with the type of education or teaching that you had at the lower levels of school, because very often, things we are really interested in or try to be curious about are affected by the quality of our teachers. So, maybe in your case, you just weren’t fortunate enough to have a very good math teacher in high school or even elementary school.
IRA FLATOW: Well, in my case, sometimes I’m just not smart enough, you know? But it doesn’t make me less curious, and it doesn’t stop me from trying to find out.
MARIO LIVIO: Exactly.
IRA FLATOW: I mean, there may be an inability to understand certain concepts, but curiosity can be so strong, right, that you just keep– you keep plugging away at it.
MARIO LIVIO: Well, look. Let me go back to Leonardo. Leonardo was very weak in mathematics, and that didn’t stop him from being the genius that he was. Feynman, on the other hand, in spite of the fact that he studied art and studied drawing, in particular– he became a decent drawer or drafts person, but he was never a Leonardo when it came to art. So, we have different talents.
IRA FLATOW: Does it help you cope with the world at all, being a curious person?
MARIO LIVIO: Oh, absolutely, in many, many ways. I mean, one thing which I in particular advertise in the book, and which I coined even a phrase for this– although I discovered later that I’m not the first to have thought of that– which is, curiosity is the best remedy for fear. And I strongly believe in that. You see, very often we are afraid of things that we don’t know much about or we don’t understand. And if we become curious about them and learn more about them, then we are much less afraid.
IRA FLATOW: Interesting. We’re going to take a break, come back and finish up talking with Mario Livio. Why? What Makes Us Curious, his new book– you will be curious to read it, so stay with us. We’ll be right back after this break.
This is Science Friday. I’m Ira Flatow. We’re talking about curiosity, why we possess it, and maybe how to foster it, with astrophysicist and author Mario Livio. His new book is Why? What Makes Us Curious. It was out this summer. And before the break, we were talking about curiosity and fear, and let me pick up on that theme, because there are a few phone calls and tweets about that. Let me take a phone call from Joshua in Alexandria, Virginia. Hi, welcome to Science Friday.
JOSHUA: Hi. Thank you for taking my call. To follow up on his last point, I was curious if you think the purpose of curiosity is actually to control our feelings of anxiety, and kind of, ultimately, our fear of death. You had said that it seems like we have an almost outsized curiosity that goes beyond our needs for safety, but I’m wondering if you think that that reflects our bottomless well anxiety over life in general, maybe.
MARIO LIVIO: I think that surely there is a component of that, but it surely can not relieve all of our anxiety, because, for example, that perceptual curiosity, that thing that feels like an itch we need to scratch, it in itself generates a certain amount of anxiety. It’s a different type of anxiety, but still some anxiety in the sense that– think about this.
When you are trying to remember, who was the author who wrote The Old Man and the Sea? And sometimes, that can really bother you for a few hours. Of course, today we can address that very quickly using Google, but it’s– so, it generates its own some type of anxiety. But I agree with you that it can definitely relieve the type of anxiety that we feel because of things that are unknown or misunderstood.
IRA FLATOW: But there is also the dark side to curiosity. For example, many people have tweeted– Sidney’s tweeted, did it really kill the cat? I mean, you’re associating it with something not to do. Don’t do it, right?
MARIO LIVIO: Yes. I am very much against that particular phrase. And it also, by the way, has a rejoinder which is, but satisfaction brought it back. So–
IRA FLATOW: Schrodinger’s cat.
MARIO LIVIO: So, the thing is– you see, if you look throughout history, there have been entire periods where either oppressive regimes or various types of ideologies tried to build walls around certain types of knowledge, and say, OK, you shouldn’t be curious about that, because this is not good for you.
I very much object to that. I think that we should be curious. Of course, there are things that– there is a sort of bad side of curiosity, which is, you shouldn’t eavesdrop on what your neighbors are talking, or things of that, or the NSA shouldn’t listen on our phone calls. But this is– I’m talking about the good type of curiosity, the one that teaches you, the love of knowledge, all that type of stuff. And for that, we should object to the attempts, even, to try to suppress our curiosity.
IRA FLATOW: Let’s see if we can take a call or two in here. Let’s go to Julia in Orlando. Hi, Julia.
IRA FLATOW: Hi there.
JULIA: Hi. I’m calling to ask whether greater access to information has somehow affected curiosity. Where in the olden days, we’d have to go find the answer to something in the Encyclopedia Britannica or a pub library or something, and now we can answer our questions in a moment by using Google or another search.
IRA FLATOW: That’s a great question. Great question. Very–
MARIO LIVIO: Yeah. It’s an important one, too, because it’s really a cultural change. So, there is one type of curiosity that I haven’t mentioned yet, which is specific curiosity. That is when you need a very specific piece of information, like who said, we’re all in the gutter, but some of us are looking at the stars, which happens to be Oscar Wilde.
So, to answer those questions, the internet is of course fantastic, and it relieves us of that specific type of curiosity very, very quickly. However, please note that what we do when we do scientific research or big artistic projects– we’re trying to look for answers for questions to which we don’t know the answers yet.
And that means that we cannot find those answers on the internet. So, what I think happened is that technology has allowed us to get rid of those immediate specific curiosity types of things, but it still allows us to continue to be epistemically very, very curious.
IRA FLATOW: Do you feel sorry for people who are not really very curious like you are?
MARIO LIVIO: I don’t know if I feel sorry for them, because, I mean, different people have different types of qualities. Maybe they have–
IRA FLATOW: But there’s an enjoyment– I mean, I can hear in your voice, and I know in my own life, there’s an enjoyment about being curious that people may not share.
MARIO LIVIO: I agree. I mean, I agree. I agree. But as I said, most people are curious about something. I mean, their level of curiosity may be somewhat different, but– you know, you gave that story about your friend of yours, that she is very interested in cranes and things. So, you know, she may be extremely curious about cranes. So, you don’t find that particularly interesting, but obviously she does.
IRA FLATOW: Yeah. Well somebody else might be extremely curious about Nietzsche or some– or a philosopher or something like that, and I don’t find that interesting. But I find it’s interesting that you may be curious– that it’s good to be curious about something.
MARIO LIVIO: I agree. I agree.
IRA FLATOW: Because I’m very curious about stuff, I can understand other people being geeky about other things that I’m not geeky about. But I understand where they’re coming from.
MARIO LIVIO: Look, the only reason I ended up doing all this research on curiosity and writing this book is because I became extremely curious about curiosity and how it works.
IRA FLATOW: Yeah. And it’s a great book. Like all your books, Mario, I want to recommend it to everybody. It’s called Why? What Makes Us Curious by a great astrophysicist and a great popularizer of science, Mario Livio. And you can read an excerpt from his book on our website at sciencefriday.com/why.
Thank you Mario. Thanks for taking the time–
MARIO LIVIO: Thank you.
IRA FLATOW: It was always fun, as always. Well, we’ll have you back.
MARIO LIVIO: My pleasure.
IRA FLATOW: You’re welcome.