#MathScienceMusic Ep. 1 - Vijay Iyer - Biological Foundations of Music

My name is Vijay Iyer. I'm a pianist, composer, bandleader, improviser, electronic musician. I make music with a lot of people from all over the world. I collaborate with people in a lot of different areas of music and other artistic disciplines. I'm also a professor of music at Harvard University. I'm here today to talk to you about the biological foundations of music. What is music? Why do we do it? What does it do for us as a species? What I'd like to convey to you today is the idea that music is the sound of bodies in motion.

There's a research field known as music cognition. There are scientists from psychology, neuroscience, computer science trying to understand the basic foundations of how music works, how we hear it, how we perceive it, how we make sense of it, and how we make it. I was a musician for a long time, I still am. I grew up playing music and I am a professional pianist and composer. I traveled all over the world playing concerts. I make my own music. When I started learning about this research field, I started to think that maybe they were missing something. Particularly what they were missing was the experience of doing it and knowing what it feels like to do it. So when I was in my 20s, I started studying this subject very seriously. Basically, I wanted to study music on my own terms. I did this by working on music in the way that I did, creating my own music, touring, encountering lots of musicians from all over the world and collaborating with them, and getting a sense of what's in common when you look across cultures. What is it that we all do when we do music? What do we even mean when we say music? What I came to believe is that if there's one thing we all have in common, it's our bodies. We all have the same kind of structure in the same way of moving in the world. Each person is unique and has his or her own way of doing that, but at the foundation, the foundational structure of how our bodies work informs everything that we all do. So my basic assertion is that what music is is exactly the sound of ourselves. It's what we sound like when we are in time together.

I mean to ask a question like: What is music? What is it made of? How do we perceive it? How do we distinguish it from non-musical sound? Or even larger questions like: Why do we have music? Why does it exist in every human culture along with dance? That is a simple fact of the human species: every culture on earth has both music and dance coexisting. So you start to ask: Why does music do something special for us that nothing else does? Does it have some special benefit? For example, in the way that speech does. The fact that we all have language means we can communicate, we can develop ideas, we can plan, we can talk about something that happened yesterday or a year ago. We can tell the difference between those things. Language helps us do that. Does music do something similar? Does it help us? Does it have some kind of force that nothing else can do for us? We ask ourselves these questions, but they might be trick questions in a way because we might be assuming something about what music is before we even ask it. So I'd like to look at those basic assumptions.

One of my colleagues here at Harvard is a famous evolutionary biologist named Steven Pinker, and he said something almost 20 years ago which I violently disagree with. So I wanted to share that point of view with you in order to critique it and maybe offer some alternative perspectives. He's a very influential and brilliant scientist, but this particular perspective on music I feel is missing something. It was at a conference in 1997 that I attended as a young graduate student, and he was giving a keynote on his speculations about the same topic: the biological foundations of music, where music comes from, why we have it. His perspective was that music is auditory cheesecake. What does that mean? Why cheesecake? Sounds like a joke, right? Well, let's think about cheesecake. If you know about it, I realize it's a very American thing, so you might not have ever heard of anything called cheesecake. Why would you want cake made of cheese? But this is a very rich dessert. By rich, I mean it's very sweet, full of fat and calories, very filling, and it's not good for you. But why do we like cheesecake? Or why do some people like cheesecake? I'm not sure I like it. But people like cheesecake because it has some sort of concentrated dose of things that we've evolved to need: sugar and fat, which we need in small doses. If you think about how humans evolved, it was in the context of scarcity. We didn't have food around; we had to forage for it. So certain things our bodies evolved to crave because when we had them, it would feel like a reward. That's because our body needed it. So you could say that the reason we like cheesecake is because in small doses its ingredients are good for us, but cheesecake itself is a mega dose of stuff that you don't need that much of. It just happens to be delicious to some people, but it's not really serving any evolutionary benefit. So that was his perspective, Steven Pinker's perspective on music: that basically music does the same thing. It gives you a concentrated dose of things that you need or that you are good at finding or perceiving, but he believed that music itself has no particular nutritional benefit.

So what are those things that he thinks that we need that music has in small doses or in large doses? Partly it was that our systems of hearing have evolved so that we're really good at hearing the harmonic tone of a human voice. By harmonic, I mean that when you hear a voice, it sounds like a voice. It sounds like it has a pitch. I can sing a note like this, a pitch, and you can figure out what that pitch is. You could sing it back to me. So we're good at hearing each other. You could say that the ear and the structure of the voice evolved together so that we can hear each other very well. The range of human hearing is, as you know, the range of a human voice is right in the center of the range of human hearing. Then we grow up hearing our mother's voice and maybe a father's voice. We hear, maybe when you're a baby, you hear your mother singing lullabies to you. That's important because it helps us recognize each other, it helps us find each other in the context of scarcity and danger, and it's soothing and protective. So he believes that music is just made of those kinds of things that happen to be good for you in small doses, but what we did is we kind of made cheesecake out of it. In other words, music is nothing except merely delicious. So I'd like to offer maybe some other perspectives.

I remember at that talk in '97, I asked him a question: Do you have any thoughts on the role of group psychology and the evolution of groups, not just of individuals, because we listen together? He said that his perspective on listening, the ideal listening subject for him, is somebody sitting alone with headphones. That's how he understands music. Of course, the possibility to listen to music in that way is only a hundred years old, but the human species is a hundred thousand years old. It's older than anything we can imagine. It's older than anything that you know about people. We've been around for a long time, and we've been making music the entire time. We only started listening to records or to MP3s or to YouTube or to SoundCloud or any of that stuff very recently. So before a hundred years ago, when we heard music, what it meant was that we were hearing each other. Humans always made music with and for and among each other. The mediation by technology is very recent and has no evolutionary significance when you think about it. So then we have to think a little bit differently about what music might be doing for us. It's not about the solitary experience. It seems like it has to be about something more contextual, more cultural, more social.

Another perspective is from a scientist and evolutionary biologist named Mark Changizi. He has written a couple of books: one is called The Vision Revolution and the other is called Harnessed. Both of them talk about how the hallmarks of what we call civilization are composed of units that we evolved to recognize. He argues that music takes advantage of the skills that we already have of recognizing and decoding audible traces of human action, which of course includes the voice but also includes footsteps and other actions of the body. So instead of emphasizing things like pitch and harmony and the other sorts of areas of music that scientists in music perception have tended to focus on in the past, Mark Changizi focuses on the way our perceptual systems are attuned to the sounds of human motion, how we're good at hearing each other. I'm talking about just everyday human moving around sounds: the sound and rhythmic profile of footsteps as a marker of locomotive behavior, hearing a body move around. There's also this thing called the Doppler shift, which you may know if you live in a city. When you hear a siren going by like an ambulance, as it's coming towards you its pitch seems to go up, and as it's going away from you its pitch seems to go down. As it's in motion, you hear its pitch constantly changing. The fact is that even when we're moving around in relation to each other, or when you hear someone running towards you, you hear very subtle Doppler shifts. They're not as extreme as when you hear an ambulance going by, but you can tell just from that what direction they're coming from and going to. You're actually better at it than you might think you are. We can tell something about the space around us because it helps us hear each other better. There's also a correspondence between loudness and distance. You can tell how far someone is from you just by how loud they are. Even if they're shouting at you, they might be shouting from far away, and the difference between shouting from far away and whispering next to you is pretty clear. These are things that we're good at doing. We're also better than we realize we are at hearing the space around us.

There's a story that a friend of mine told about the great Stevie Wonder, who everyone in the world knows is one of the greatest musicians alive and one of the greatest performing artists of today or of the 20th century. Also, many people know that he is blind, and that's never made it impossible for him to play music. In fact, it may have made it easier for him to focus on it and become one of the best in the world at it. I won't venture a guess about that, but there's a story about him. This was in the 1970s. Someone I know rode in an elevator with him up to the top floor of a skyscraper in New York to visit an office on the top floor that was the office for a record company. When he came out of the elevator, they walked into an atrium that was shaped like a pyramid. As soon as they came out of the elevator, Stevie Wonder moved his head around and said, 'Something's up with this room. It's like the walls are triangular.' So he knew just by listening. That's because he's refined that skill, but it's a skill that we actually all have: to hear the space around us and how sound reflects off of it. This is how we are able to hear each other in a very refined and detailed way. We can tell from footsteps whether it's a man or woman walking. There are lots of little details like that because of the ratio. Women tend to have a lower center of gravity in their bodies, which means that the ratio of the time between the landing of the heel and the toe ends up being different than it is for men. So we're generally able to tell, even without thinking about it, whether it's a man or woman walking nearby. This is something that we've evolved to do as a species, and we're good at it.

So Mark Changizi argues that rather than suggesting that we evolved to hear music, the point is that music comes from us harnessing an existing perceptual apparatus which had evolved already for the perception of human motion. It evolved so that we could develop music. So rather than suggest that humans evolved to hear music, Mark Changizi argues that humans harnessed an existing perceptual apparatus which had evolved already for the purpose of hearing each other, perceiving human motion, and that was then used to develop this thing that we call music, which he claims mimics human action. But I would even go farther than that. It's not that music mimics human action; it's that it is human action. Where else does it come from? Again, in the last century, we've gotten used to music circulating without people. We listen to records, we listen to files, CDs, or cassettes that are some sort of document of some action that happened before, or they might be electronic music made by machines. But that's all very recent. What we did before was we listened to each other making music. So it was always the sound, not just of an imitation of human action, but it was the sound of human action. That's an important distinction to make, so that we never forget that music is us.

Changizi made an analogy to written language. Written language takes advantage of our visual ability to notice contours, edges, and joints. These are the building blocks of human vision. It's how the eye works, it's how the brain behind the eye processes the information coming into the eye, how it decodes it from this constant wash of light entering the eye, breaks it down into edges, contours, joints. So we see where things begin and end. If you look at lettering, just how what languages are made with, written language is made of things like that: edges, contours, and joints. This is true across all the human languages that are written. So that's another example of how harnessing works. It basically is about taking something that the perceptual system is good at doing and finding and using, and doing something with it, building something out of it that then enhances and extends what humanity can do.

So music is more than a mere sonic imitation of human action. Until recently, it was never anything but human action. It was the sound of us making sounds. Music was always made by our bodily engagement with whatever technology was available. So the sound of music was always the sound of bodies in motion. These sounds could be made through pure bodily acts like stomping, clapping, any kind of slapping of skin together, singing, of course, shouting, grunting, beatboxing, all the things you can do with your body. If you've ever heard an a cappella singing group, you've heard a lot of different range of sounds that we can make just by ourselves without any instruments. The earliest instruments were objects adapted from the natural world: gourds, logs, animal skins stretched over a hole in a piece of wood, maybe the bones of a chicken or something else like that. Eventually, these objects became more refined and turned into things like the piano or the drum set or a cowbell or a saxophone. Later, you're going to meet a dear friend and colleague of mine named Yosvany Terry. He's a musician and composer, bandleader, and one of my colleagues here at Harvard University. He's a senior lecturer in music and the director of jazz bands, and he is a fantastic saxophonist. But also, he comes from a family of musicians, and his father is the greatest chekere player in the world. Chekere is an instrument made from a gourd. You'll learn more about it.