How I climbed a 3,000-foot vertical cliff without ropes
Hello. I'd like to show you guys 30 seconds of the best day of my life.
So that was El Capitan in California's Yosemite National Park, and in case you couldn't tell, I was climbing by myself without a rope, a style of a climbing known as free soloing. That was the culmination of a nearly decade-long dream, and in the video I'm over 2,500 feet off the ground. Seems scary? Yeah, it is, which is why I spent so many years dreaming about soloing El Cap and not actually doing it. But on the day that that video was taken, it didn't feel scary at all. It felt as comfortable and natural as a walk in the park, which is what most folks were doing in Yosemite that day.
Today I'd like to talk about how I was able to feel so comfortable and how I overcame my fear. I'll start with a very brief version of how I became a climber, and then tell the story of my two most significant free solos. They were both successful, which is why I'm here.
But the first felt largely unsatisfying, whereas the second, El Cap, was by far the most fulfilling day of my life. Through these two climbs, you'll see my process for managing fear.
So I started climbing in a gym when I was around 10 years old, which means that my life has been centered on climbing for more than 20 years. After nearly a decade of climbing mostly indoors, I made the transition to the outdoors and gradually started free soloing. I built up my comfort over time and slowly took on bigger and more challenging walls. And there have been many free soloists before me, so I had plenty of inspiration to draw from. But by 2008, I'd repeated most of their previous solos in Yosemite and was starting to imagine breaking into new terrain. The obvious first choice was Half Dome, an iconic 2,000-foot wall that lords over the east end of the valley.
The problem, though also the allure, was that it was too big. I didn't really know how to prepare for a potential free solo. So I decided to skip the preparations and just go up there and have an adventure. I figured I would rise to the occasion, which, unsurprisingly, was not the best strategy.
I did at least climb the route roped up with a friend two days before just to make sure that I knew roughly where to go and that I could physically do it. But when I came back by myself two days later, I decided that I didn't want to go that way. I knew that there was a 300-foot variation that circled around one of the hardest parts of the climb. I suddenly decided to skip the hard part and take the variation, even though I'd never climbed it before, but I immediately began to doubt myself. Imagine being by yourself in the dead center of a 2,000-foot face, wondering if you're lost.
Thankfully, it was pretty much the right way and I circled back to the route. I was slightly rattled, I was pretty rattled, but I tried not to let it bother me too much because I knew that all the hardest climbing was up at the top. I needed to stay composed. It was a beautiful September morning, and as I climbed higher, I could hear the sounds of tourists chatting and laughing on the summit. They'd all hiked up the normal trail on the back, which I was planning on using for my descent. But between me and the summit lay a blank slab of granite. There were no cracks or edges to hold on to, just small ripples of texture up a slightly less than vertical wall. I had to trust my life to the friction between my climbing shoes and the smooth granite. I carefully balanced my way upward, shifting my weight back and forth between the small smears. But then I reached a foothold that I didn't quite trust. Two days ago, I'd have just stepped right up on it, but that would have been with a rope on. Now it felt too small and too slippery. I doubted that my foot would stay on if I weighted it. I considered a foot further to the side, which seemed worse. I switched my feet and tried a foot further out. It seemed even worse. I started to panic. I could hear people laughing on the summit just above me. I wanted to be anywhere but on that slab. My mind was racing in every direction. I knew what I had to do, but I was too afraid to do it. I just had to stand up on my right foot. And so after what felt like an eternity, I accepted what I had to do and I stood up on the right foot, and it didn't slip, and so I didn't die, and that move marked the end of the hardest climbing. And so I charged from there towards the summit. And so normally when you summit Half Dome, you have a rope and a bunch of climbing gear on you, and tourists gasp and they flock around you for photos. This time I popped over the edge shirtless, panting, jacked. I was amped, but nobody batted an eye.
I looked like a lost hiker that was too close to the edge. I was surrounded by people talking on cell phones and having picnics. I felt like I was in a mall.
I took off my tight climbing shoes and started hiking back down, and that's when people stopped me. "You're hiking barefoot? That's so hard-core."
I didn't bother to explain, but that night in my climbing journal, I duly noted my free solo of Half Dome, but I included a frowny face and a comment, "Do better?"
I'd succeeded in the solo and it was celebrated as a big first in climbing. Some friends later made a film about it. But I was unsatisfied. I was disappointed in my performance, because I knew that I had gotten away with something. I didn't want to be a lucky climber. I wanted to be a great climber. I actually took the next year or so off from free soloing, because I knew that I shouldn't make a habit of relying on luck. But even though I wasn't soloing very much, I'd already started to think about El Cap. It was always in the back of my mind as the obvious crown jewel of solos. It's the most striking wall in the world. Each year, for the next seven years, I'd think, "This is the year that I'm going to solo El Cap." And then I would drive into Yosemite, look up at the wall, and think, "No frickin' way."
It's too big and too scary. But eventually I came to accept that I wanted to test myself against El Cap. It represented true mastery, but I needed it to feel different. I didn't want to get away with anything or barely squeak by. This time I wanted to do it right.
The thing that makes El Cap so intimidating is the sheer scale of the wall. Most climbers take three to five days to ascend the 3,000 feet of vertical granite. The idea of setting out up a wall of that size with nothing but shoes and a chalk bag seemed impossible. 3,000 feet of climbing represents thousands of distinct hand and foot movements, which is a lot to remember. Many of the moves I knew through sheer repetition. I'd climbed El Cap maybe 50 times over the previous decade with a rope. But this photo shows my preferred method of rehearsing the moves. I'm on the summit, about to rappel down the face with over a thousand feet of rope to spend the day practicing. Once I found sequences that felt secure and repeatable, I had to memorize them. I had to make sure that they were so deeply ingrained within me that there was no possibility of error. I didn't want to be wondering if I was going the right way or using the best holds. I needed everything to feel automatic.
Climbing with a rope is a largely physical effort. You just have to be strong enough to hold on and make the movements upward. But free soloing plays out more in the mind. The physical effort is largely the same. Your body is still climbing the same wall. But staying calm and performing at your best when you know that any mistake could mean death requires a certain kind of mindset.
That's not supposed to be funny, but if it is, it is.
I worked to cultivate that mindset through visualization, which basically just means imagining the entire experience of soloing the wall. Partially, that was to help me remember all the holds, but mostly visualization was about feeling the texture of each hold in my hand and imagining the sensation of my leg reaching out and placing my foot just so. I'd imagine it all like a choreographed dance thousands of feet up.
The most difficult part of the whole route was called the Boulder Problem. It was about 2,000 feet off the ground and consisted of the hardest physical moves on the whole route: long pulls between poor handholds with very small, slippery feet. This is what I mean by a poor handhold: an edge smaller than the width of a pencil but facing downward that I had to press up into with my thumb. But that wasn't even the hardest part. The crux culminated in a karate kick with my left foot over to the inside of an adjacent corner, a maneuver that required a high degree of precision and flexibility, enough so that I'd been doing a nightly stretching routine for a full year ahead of time to make sure that I could comfortably make the reach with my leg.
As I practiced the moves, my visualization turned to the emotional component of a potential solo. Basically, what if I got up there and it was too scary? What if I was too tired? What if I couldn't quite make the kick? I had to consider every possibility while I was safely on the ground, so that when the time came and I was actually making the moves without a rope, there was no room for doubt to creep in. Doubt is the precursor to fear, and I knew that I couldn't experience my perfect moment if I was afraid. I had to visualize and rehearse enough to remove all doubt.
But beyond that, I also visualized how it would feel if it never seemed doable. What if, after so much work, I was afraid to try? What if I was wasting my time and I would never feel comfortable in such an exposed position? There were no easy answers, but El Cap meant enough to me that I would put in the work and find out.
Some of my preparations were more mundane. This is a photo of my friend Conrad Anker climbing up the bottom of El Cap with an empty backpack. We spent the day climbing together to a specific crack in the middle of the wall that was choked with loose rocks that made that section difficult and potentially dangerous, because any missed step might knock a rock to the ground and kill a passing climber or hiker. So we carefully removed the rocks, loaded them into the pack and rappelled back down. Take a second to imagine how ridiculous it feels to climb 1,500 feet up a wall just to fill a backpack full of rocks.
It's never that easy to carry a pack full of rocks around. It's even harder on the side of a cliff. It may have felt silly, but it still had to get done. I needed everything to feel perfect if I was ever going to climb the route without a rope. After two seasons of working specifically toward a potential free solo of El Cap, I finally finished all my preparations. I knew every handhold and foothold on the whole route, and I knew exactly what to do. Basically, I was ready. It was time to solo El Cap.
On June 3, 2017, I woke up early, ate my usual breakfast of muesli and fruit and made it to the base of the wall before sunrise. I felt confident as I looked up the wall. I felt even better as I started climbing. About 500 feet up, I reached a slab very similar to the one that had given me so much trouble on Half Dome, but this time was different. I'd scouted every option, including hundreds of feet of wall to either side. I knew exactly what to do and how to do it. I had no doubts. I just climbed right through. Even the difficult and strenuous sections passed by with ease. I was perfectly executing my routine. I rested for a moment below the Boulder Problem and then climbed it just as I had practiced so many times with the rope on. My foot shot across to the wall on the left without hesitation, and I knew that I had done it.
Climbing Half Dome had been a big goal and I did it, but I didn't get what I really wanted. I didn't achieve mastery. I was hesitant and afraid, and it wasn't the experience that I wanted. But El Cap was different. With 600 feet to go, I felt like the mountain was offering me a victory lap. I climbed with a smooth precision and enjoyed the sounds of the birds swooping around the cliff. It all felt like a celebration. And then I reached the summit after three hours and 56 minutes of glorious climbing. It was the climb that I wanted, and it felt like mastery.
Thank you.
The brain-changing benefits of exercise
What if I told you there was something that you can do right now that would have an immediate, positive benefit for your brain including your mood and your focus? And what if I told you that same thing could actually last a long time and protect your brain from different conditions like depression, Alzheimer's disease or dementia. Would you do it? Yes!
I am talking about the powerful effects of physical activity. Simply moving your body, has immediate, long-lasting and protective benefits for your brain. And that can last for the rest of your life. So what I want to do today is tell you a story about how I used my deep understanding of neuroscience, as a professor of neuroscience, to essentially do an experiment on myself in which I discovered the science underlying why exercise is the most transformative thing that you can do for your brain today. Now, as a neuroscientist, I know that our brains, that is the thing in our head right now, that is the most complex structure known to humankind. But it's one thing to talk about the brain, and it's another to see it.
So here is a real preserved human brain. And it's going to illustrate two key areas that we are going to talk about today. The first is the prefrontal cortex, right behind your forehead, critical for things like decision-making, focus, attention and your personality. The second key area is located in the temporal lobe, shown right here. You have two temporal lobes in your brain, the right and the left, and deep in the temporal lobe is a key structure critical for your ability to form and retain new long-term memories for facts and events. And that structure is called the hippocampus. So I've always been fascinated with the hippocampus. How could it be that an event that lasts just a moment, say, your first kiss, or the moment your first child was born, can form a memory that has changed your brain, that lasts an entire lifetime? That's what I want to understand. I wanted to start and record the activity of individual brain cells in the hippocampus as subjects were forming new memories. And essentially try and decode how those brief bursts of electrical activity, which is how neurons communicate with each other, how those brief bursts either allowed us to form a new memory, or did not.
But a few years ago, I did something very unusual in science. As a full professor of neural science, I decided to completely switch my research program. Because I encountered something that was so amazing, with the potential to change so many lives that I had to study it. I discovered and I experienced the brain-changing effects of exercise. And I did it in a completely inadvertent way. I was actually at the height of all the memory work that I was doing data was pouring in, I was becoming known in my field for all of this memory work. And it should have been going great. It was, scientifically. But when I stuck my head out of my lab door, I noticed something. I had no social life. I spent too much time listening to those brain cells in a dark room, by myself. I didn't move my body at all. I had gained 25 pounds. And actually, it took me many years to realize it, I was actually miserable. And I shouldn't be miserable. And I went on a river-rafting trip by myself, because I had no social life. And I came back
thinking, "Oh, my God, I was the weakest person on that trip." And I came back with a mission. I said, "I'm never going to feel like the weakest person on a river-rafting trip again." And that's what made me go to the gym. And I focused my type-A personality on going to all the exercise classes at the gym. I tried everything. I went to kickbox, dance, yoga, step class, and at first it was really hard. But what I noticed is that after every sweat-inducing workout that I tried, I had this great mood boost and this great energy boost. And that's what kept me going back to the gym. Well, I started feeling stronger. I started feeling better, I even lost that 25 pounds.
And now, fast-forward a year and a half into this regular exercise program and I noticed something that really made me sit up and take notice. I was sitting at my desk, writing a research grant, and a thought went through my mind that had never gone through my mind before. And that thought was, "Gee, grant-writing is going well today." And all the scientists
yeah, all the scientists always laugh when I say that, because grant-writing never goes well. It is so hard; you're always pulling your hair out, trying to come up with that million-dollar-winning idea. But I realized that the grant-writing was going well, because I was able to focus and maintain my attention for longer than I had before. And my long-term memory what I was studying in my own lab seemed to be better in me. And that's when I put it together.
Maybe all that exercise that I had included and added to my life was changing my brain. Maybe I did an experiment on myself without even knowing it. So as a curious neuroscientist, I went to the literature to see what I could find about what we knew about the effects of exercise on the brain. And what I found was an exciting and a growing literature that was essentially showing everything that I noticed in myself. Better mood, better energy, better memory, better attention. And the more I learned, the more I realized how powerful exercise was. Which eventually led me to the big decision to completely shift my research focus. And so now, after several years of really focusing on this question, I've come to the following conclusion: that exercise is the most transformative thing that you can do for your brain today for the following three reasons.
Number one: it has immediate effects on your brain. A single workout that you do will immediately increase levels of neurotransmitters like dopamine, serotonin and noradrenaline. That is going to increase your mood right after that workout, exactly what I was feeling. My lab showed that a single workout can improve your ability to shift and focus attention, and that focus improvement will last for at least two hours. And finally, studies have shown that a single workout will improve your reaction times which basically means that you are going to be faster at catching that cup of Starbucks that falls off the counter, which is very, very important.
But these immediate effects are transient, they help you right after. What you have to do is do what I did, that is change your exercise regime, increase your cardiorespiratory function, to get the long-lasting effects. And these effects are long-lasting because exercise actually changes the brain's anatomy, physiology and function. Let's start with my favorite brain area, the hippocampus. The hippocampus or exercise actually produces brand new brain cells, new brain cells in the hippocampus, that actually increase its volume, as well as improve your long-term memory, OK? And that including in you and me.
Number two: the most common finding in neuroscience studies, looking at effects of long-term exercise, is improved attention function dependent on your prefrontal cortex. You not only get better focus and attention, but the volume of the hippocampus increases as well. And finally, you not only get immediate effects of mood with exercise but those last for a long time. So you get long-lasting increases in those good mood neurotransmitters.
But really, the most transformative thing that exercise will do is its protective effects on your brain. Here you can think about the brain like a muscle. The more you're working out, the bigger and stronger your hippocampus and prefrontal cortex gets. Why is that important? Because the prefrontal cortex and the hippocampus are the two areas that are most susceptible to neurodegenerative diseases and normal cognitive decline in aging. So with increased exercise over your lifetime, you're not going to cure dementia or Alzheimer's disease, but what you're going to do is you're going to create the strongest, biggest hippocampus and prefrontal cortex so it takes longer for these diseases to actually have an effect. You can think of exercise, therefore, as a supercharged 401K for your brain, OK? And it's even better, because it's free.
So this is the point in the talk where everybody says, "That sounds so interesting, Wendy, but I really will only want to know one thing. And that is, just tell me the minimum amount of exercise I need to get all these changes."
And so I'm going to tell you the answer to that question. First, good news: you don't have to become a triathlete to get these effects. The rule of thumb is you want to get three to four times a week exercise minimum 30 minutes an exercise session, and you want to get aerobic exercise in. That is, get your heart rate up. And the good news is, you don't have to go to the gym to get a very expensive gym membership. Add an extra walk around the block in your power walk. You see stairs take stairs. And power-vacuuming can be as good as the aerobics class that you were going to take at the gym.
So I've gone from memory pioneer to exercise explorer. From going into the innermost workings of the brain, to trying to understand how exercise can improve our brain function, and my goal in my lab right now is to go beyond that rule of thumb that I just gave you three to four times a week, 30 minutes. I want to understand the optimum exercise prescription for you, at your age, at your fitness level, for your genetic background, to maximize the effects of exercise today and also to improve your brain and protect your brain the best for the rest of your life.
But it's one thing to talk about exercise, and it's another to do it. So I'm going to invoke my power as a certified exercise instructor, to ask you all to stand up.
We're going to do just one minute of exercise. It's call-and-response, just do what I do, say what I say, and make sure you don't punch your neighbor, OK? Music!
(Upbeat music)
Five, six, seven, eight, it's right, left, right, left. And I say, I am strong now. Let's hear you.
Audience: I am strong now.
Wendy Suzuki: Ladies, I am Wonder Woman-strong. Let's hear you!
Audience: I am Wonder Woman-strong.
WS: New move uppercut, right and left. I am inspired now. You say it!
Audience: I am inspired now.
WS: Last move pull it down, right and left, right and left. I say, I am on fire now! You say it.
Audience: I am on fire now.
WS: And done! OK, good job!
Thank you. I want to leave you with one last thought. And that is, bringing exercise in your life will not only give you a happier, more protective life today, but it will protect your brain from incurable diseases. And in this way it will change the trajectory of your life for the better.
Thank you very much.
How to let go of being a "good" person and become a better person
So a friend of mine was riding in a taxi to the airport the other day, and on the way, she was chatting with the taxi driver, and he said to her, with total sincerity, "I can tell you are a really good person." And when she told me this story later, she said she couldn't believe how good it made her feel, that it meant a lot to her. Now that may seem like a strong reaction from my friend to the words of a total stranger, but she's not alone.
I'm a social scientist. I study the psychology of good people, and research in my field says many of us care deeply about feeling like a good person and being seen as a good person. Now, your definition of "good person" and your definition of "good person" and maybe the taxi driver's definition of "good person" we may not all have the same definition, but within whatever our definition is, that moral identity is important to many of us.
Now, if somebody challenges it, like they question us for a joke we tell, or maybe we say our workforce is homogenous, or a slippery business expense, we go into red-zone defensiveness a lot of the time. I mean, sometimes we call out all the ways in which we help people from marginalized groups, or we donate to charity, or the hours we volunteer to nonprofits. We work to protect that good person identity. It's important to many of us.
But what if I told you this? What if I told you that our attachment to being good people is getting in the way of us being better people? What if I told you that our definition of "good person" is so narrow, it's scientifically impossible to meet? And what if I told you the path to being better people just begins with letting go of being a good person?
Now, let me tell you a little bit about the research about how the human mind works to explain. The brain relies on shortcuts to do a lot of its work. That means a lot of the time, your mental processes are taking place outside of your awareness, like in low-battery, low-power mode in the back of your mind. That's, in fact, the premise of bounded rationality. Bounded rationality is the Nobel Prize-winning idea that the human mind has limited storage resources, limited processing power, and as a result, it relies on shortcuts to do a lot of its work. So for example, some scientists estimate that in any given moment ... Better, better click, right? There we go.
At any given moment, 11 million pieces of information are coming into your mind. Eleven million. And only 40 of them are being processed consciously. So 11 million, 40.
I mean, has this ever happened to you? Have you ever had a really busy day at work, and you drive home, and when you get in the door, you realize you don't even remember the drive home, like whether you had green lights or red lights. You don't even remember. You were on autopilot. Or have you ever opened the fridge, looked for the butter, swore there is no butter, and then realized the butter was right in front of you the whole time? These are the kinds of "whoops" moments that make us giggle, and this is what happens in a brain that can handle 11 million pieces of information coming in with only 40 being processed consciously. That's the bounded part of bounded rationality.
This work on bounded rationality is what's inspired work I've done with my collaborators Max Bazerman and Mahzarin Banaji, on what we call bounded ethicality. So it's the same premise as bounded rationality, that we have a human mind that is bounded in some sort of way and relying on shortcuts, and that those shortcuts can sometimes lead us astray. With bounded rationality, perhaps it affects the cereal we buy in the grocery store, or the product we launch in the boardroom. With bounded ethicality, the human mind, the same human mind, is making decisions, and here, it's about who to hire next, or what joke to tell or that slippery business decision.
So let me give you an example of bounded ethicality at work. Unconscious bias is one place where we see the effects of bounded ethicality. So unconscious bias refers to associations we have in our mind, the shortcuts your brain is using to organize information, very likely outside of your awareness, not necessarily lining up with your conscious beliefs. Researchers Nosek, Banaji and Greenwald have looked at data from millions of people, and what they've found is, for example, most white Americans can more quickly and easily associate white people and good things than black people and good things, and most men and women can more quickly and easily associate men and science than women and science. And these associations don't necessarily line up with what people consciously think. They may have very egalitarian views, in fact. So sometimes, that 11 million and that 40 just don't line up.
And here's another example: conflicts of interest. So we tend to underestimate how much a small gift imagine a ballpoint pen or dinner how much that small gift can affect our decision making. We don't realize that our mind is unconsciously lining up evidence to support the point of view of the gift-giver, no matter how hard we're consciously trying to be objective and professional. We also see bounded ethicality despite our attachment to being good people, we still make mistakes, and we make mistakes that sometimes hurt other people, that sometimes promote injustice, despite our best attempts, and we explain away our mistakes rather than learning from them. Like, for example, when I got an email from a female student in my class saying that a reading I had assigned, a reading I had been assigning for years, was sexist. Or when I confused two students in my class of the same race look nothing alike when I confused them for each other more than once, in front of everybody.
These kinds of mistakes send us, send me, into red-zone defensiveness. They leave us fighting for that good person identity. But the latest work that I've been doing on bounded ethicality with Mary Kern says that we're not only prone to mistakes that tendency towards mistakes depends on how close we are to that red zone. So most of the time, nobody's challenging our good person identity, and so we're not thinking too much about the ethical implications of our decisions, and our model shows that we're then spiraling towards less and less ethical behavior most of the time.
On the other hand, somebody might challenge our identity, or, upon reflection, we may be challenging it ourselves. So the ethical implications of our decisions become really salient, and in those cases, we spiral towards more and more good person behavior, or, to be more precise, towards more and more behavior that makes us feel like a good person, which isn't always the same, of course. The idea with bounded ethicality is that we are perhaps overestimating the importance our inner compass is playing in our ethical decisions. We perhaps are overestimating how much our self-interest is driving our decisions, and perhaps we don't realize how much our self-view as a good person is affecting our behavior, that in fact, we're working so hard to protect that good person identity, to keep out of that red zone, that we're not actually giving ourselves space to learn from our mistakes and actually be better people.
It's perhaps because we expect it to be easy. We have this definition of good person that's either-or. Either you are a good person or you're not. Either you have integrity or you don't. Either you are a racist or a sexist or a homophobe or you're not. And in this either-or definition, there's no room to grow. And by the way, this is not what we do in most parts of our lives. Life, if you needed to learn accounting, you would take an accounting class, or if you become a parent, we pick up a book and we read about it. We talk to experts, we learn from our mistakes, we update our knowledge, we just keep getting better. But when it comes to being a good person, we think it's something we're just supposed to know, we're just supposed to do, without the benefit of effort or growth.
So what I've been thinking about is what if we were to just forget about being good people, just let it go, and instead, set a higher standard, a higher standard of being a good-ish person? A good-ish person absolutely still makes mistakes. As a good-ish person, I'm making them all the time. But as a good-ish person, I'm trying to learn from them, own them. I expect them and I go after them. I understand there are costs to these mistakes. When it comes to issues like ethics and bias and diversity and inclusion, there are real costs to real people, and I accept that. As a good-ish person, in fact, I become better at noticing my own mistakes. I don't wait for people to point them out. I practice finding them, and as a result ... Sure, sometimes it can be embarrassing, it can be uncomfortable. We put ourselves in a vulnerable place, sometimes. But through all that vulnerability, just like in everything else we've tried to ever get better at, we see progress. We see growth. We allow ourselves to get better.
Why wouldn't we give ourselves that? In every other part of our lives, we give ourselves room to grow except in this one, where it matters most.
Thank you.
Four billion years of evolution in six minutes
If we evolved from monkeys, why are there still monkeys?Well, because we're not monkeys, we're fish.Now, knowing you're a fish and not a monkey is actually really important to understanding where we came from. I teach one of the largest evolutionary biology classes in the US, and when my students finally understand why I call them fish all the time, then I know I'm getting my job done. But I always have to start my classes by dispelling some hardwired myths, because without really knowing it, many of us were taught evolution wrong.
For instance, we're taught to say "the theory of evolution." There are actually many theories, and just like the process itself, the ones that best fit the data are the ones that survive to this day. The one we know best is Darwinian natural selection. That's the process by which organisms that best fit an environment survive and get to reproduce, while those that are less fit slowly die off. And that's it. Evolution is as simple as that, and it's a fact.
Evolution is a fact as much as the "theory of gravity." You can prove it just as easily. You just need to look at your bellybutton that you share with other placental mammals, or your backbone that you share with other vertebrates, or your DNA that you share with all other life on earth. Those traits didn't pop up in humans. They were passed down from different ancestors to all their descendants, not just us.
But that's not really how we learn biology early on, is it? We learn plants and bacteria are primitive things, and fish give rise to amphibians followed by reptiles and mammals, and then you get you, this perfectly evolved creature at the end of the line. But life doesn't evolve in a line, and it doesn't end with us. But we're always shown evolution portrayed something like this, a monkey and a chimpanzee, some extinct humans, all on a forward and steady march to becoming us. But they don't become us any more than we would become them. We're also not the goal of evolution.
But why does it matter? Why do we need to understand evolution the right way? Well, misunderstanding evolution has led to many problems, but you can't ask that age-old question, "Where are we from?" without understanding evolution the right way. Misunderstanding it has led to many convoluted and corrupted views of how we should treat other life on earth, and how we should treat each other in terms of race and gender.
So let's go back four billion years. This is the single-celled organism we all came from. At first, it gave rise to other single-celled life, but these are still evolving to this day, and some would say the Archaea and Bacteria that make up most of this group is the most successful on the planet. They are certainly going to be here well after us.
About three billion years ago, multicellularity evolved. This includes your fungi and your plants and your animals. The first animals to develop a backbone were fishes. So technically, all vertebrates are fishes, so technically, you and I are fish. So don't say I didn't warn you.
One fish lineage came onto land and gave rise to, among other things, the mammals and reptiles. Some reptiles become birds, some mammals become primates, some primates become monkeys with tails, and others become the great apes, including a variety of human species. So you see, we didn't evolve from monkeys, but we do share a common ancestor with them.
All the while, life around us kept evolving: more bacteria, more fungi, lots of fish, fish, fish. If you couldn't tell yes, they're my favorite group.
As life evolves, it also goes extinct. Most species just last for a few million years. So you see, most life on earth that we see around us today are about the same age as our species. So it's hubris, it's self-centered to think, "Oh, plants and bacteria are primitive, and we've been here for an evolutionary minute, so we're somehow special."
Think of life as being this book, an unfinished book for sure. We're just seeing the last few pages of each chapter. If you look out on the eight million species that we share this planet with, think of them all being four billion years of evolution. They're all the product of that. Think of us all as young leaves on this ancient and gigantic tree of life, all of us connected by invisible branches not just to each other, but to our extinct relatives and our evolutionary ancestors. As a biologist, I'm still trying to learn, with others, how everyone's related to each other, who is related to whom.
Perhaps it's better still to think of us as a little fish out of water. Yes, one that learned to walk and talk, but one that still has a lot of learning to do about who we are and where we came from.
Thank you.
How language shapes the way we think
So, I'll be speaking to you using language ... because I can. This is one these magical abilities that we humans have. We can transmit really complicated thoughts to one another. So what I'm doing right now is, I'm making sounds with my mouth as I'm exhaling. I'm making tones and hisses and puffs, and those are creating air vibrations in the air. Those air vibrations are traveling to you, they're hitting your eardrums, and then your brain takes those vibrations from your eardrums and transforms them into thoughts. I hope.
I hope that's happening. So because of this ability, we humans are able to transmit our ideas across vast reaches of space and time. We're able to transmit knowledge across minds. I can put a bizarre new idea in your mind right now. I could say, "Imagine a jellyfish waltzing in a library while thinking about quantum mechanics."
Now, if everything has gone relatively well in your life so far, you probably haven't had that thought before.
But now I've just made you think it, through language.
Now of course, there isn't just one language in the world, there are about 7,000 languages spoken around the world. And all the languages differ from one another in all kinds of ways. Some languages have different sounds, they have different vocabularies, and they also have different structures very importantly, different structures. That begs the question: Does the language we speak shape the way we think? Now, this is an ancient question. People have been speculating about this question forever. Charlemagne, Holy Roman emperor, said, "To have a second language is to have a second soul" strong statement that language crafts reality. But on the other hand, Shakespeare has Juliet say, "What's in a name? A rose by any other name would smell as sweet." Well, that suggests that maybe language doesn't craft reality.
These arguments have gone back and forth for thousands of years. But until recently, there hasn't been any data to help us decide either way. Recently, in my lab and other labs around the world, we've started doing research, and now we have actual scientific data to weigh in on this question.
So let me tell you about some of my favorite examples. I'll start with an example from an Aboriginal community in Australia that I had the chance to work with. These are the Kuuk Thaayorre people. They live in Pormpuraaw at the very west edge of Cape York. What's cool about Kuuk Thaayorre is, in Kuuk Thaayorre, they don't use words like "left" and "right," and instead, everything is in cardinal directions: north, south, east and west. And when I say everything, I really mean everything. You would say something like, "Oh, there's an ant on your southwest leg." Or, "Move your cup to the north-northeast a little bit." In fact, the way that you say "hello" in Kuuk Thaayorre is you say, "Which way are you going?" And the answer should be, "North-northeast in the far distance. How about you?"
So imagine as you're walking around your day, every person you greet, you have to report your heading direction.
But that would actually get you oriented pretty fast, right? Because you literally couldn't get past "hello," if you didn't know which way you were going. In fact, people who speak languages like this stay oriented really well. They stay oriented better than we used to think humans could. We used to think that humans were worse than other creatures because of some biological excuse: "Oh, we don't have magnets in our beaks or in our scales." No; if your language and your culture trains you to do it, actually, you can do it. There are humans around the world who stay oriented really well.
And just to get us in agreement about how different this is from the way we do it, I want you all to close your eyes for a second and point southeast.
Keep your eyes closed. Point. OK, so you can open your eyes. I see you guys pointing there, there, there, there, there ... I don't know which way it is myself
You have not been a lot of help.
So let's just say the accuracy in this room was not very high. This is a big difference in cognitive ability across languages, right? Where one group very distinguished group like you guys doesn't know which way is which, but in another group, I could ask a five-year-old and they would know.
There are also really big differences in how people think about time. So here I have pictures of my grandfather at different ages. And if I ask an English speaker to organize time, they might lay it out this way, from left to right. This has to do with writing direction. If you were a speaker of Hebrew or Arabic, you might do it going in the opposite direction, from right to left.
But how would the Kuuk Thaayorre, this Aboriginal group I just told you about, do it? They don't use words like "left" and "right." Let me give you hint. When we sat people facing south, they organized time from left to right. When we sat them facing north, they organized time from right to left. When we sat them facing east, time came towards the body. What's the pattern? East to west, right? So for them, time doesn't actually get locked on the body at all, it gets locked on the landscape. So for me, if I'm facing this way, then time goes this way, and if I'm facing this way, then time goes this way. I'm facing this way, time goes this way very egocentric of me to have the direction of time chase me around every time I turn my body. For the Kuuk Thaayorre, time is locked on the landscape. It's a dramatically different way of thinking about time.
Here's another really smart human trick. Suppose I ask you how many penguins are there. Well, I bet I know how you'd solve that problem if you solved it. You went, "One, two, three, four, five, six, seven, eight." You counted them. You named each one with a number, and the last number you said was the number of penguins. This is a little trick that you're taught to use as kids. You learn the number list and you learn how to apply it. A little linguistic trick. Well, some languages don't do this, because some languages don't have exact number words. They're languages that don't have a word like "seven" or a word like "eight." In fact, people who speak these languages don't count, and they have trouble keeping track of exact quantities. So, for example, if I ask you to match this number of penguins to the same number of ducks, you would be able to do that by counting. But folks who don't have that linguistic trick can't do that.
Languages also differ in how they divide up the color spectrum the visual world. Some languages have lots of words for colors, some have only a couple words, "light" and "dark." And languages differ in where they put boundaries between colors. So, for example, in English, there's a word for blue that covers all of the colors that you can see on the screen, but in Russian, there isn't a single word. Instead, Russian speakers have to differentiate between light blue, "goluboy," and dark blue, "siniy." So Russians have this lifetime of experience of, in language, distinguishing these two colors. When we test people's ability to perceptually discriminate these colors, what we find is that Russian speakers are faster across this linguistic boundary. They're faster to be able to tell the difference between a light and dark blue. And when you look at people's brains as they're looking at colors say you have colors shifting slowly from light to dark blue the brains of people who use different words for light and dark blue will give a surprised reaction as the colors shift from light to dark, as if, "Ooh, something has categorically changed," whereas the brains of English speakers, for example, that don't make this categorical distinction, don't give that surprise, because nothing is categorically changing.
Languages have all kinds of structural quirks. This is one of my favorites. Lots of languages have grammatical gender; every noun gets assigned a gender, often masculine or feminine. And these genders differ across languages. So, for example, the sun is feminine in German but masculine in Spanish, and the moon, the reverse. Could this actually have any consequence for how people think? Do German speakers think of the sun as somehow more female-like, and the moon somehow more male-like? Actually, it turns out that's the case. So if you ask German and Spanish speakers to, say, describe a bridge, like the one here "bridge" happens to be grammatically feminine in German, grammatically masculine in Spanish German speakers are more likely to say bridges are "beautiful," "elegant" and stereotypically feminine words. Whereas Spanish speakers will be more likely to say they're "strong" or "long," these masculine words.
Languages also differ in how they describe events, right? You take an event like this, an accident. In English, it's fine to say, "He broke the vase." In a language like Spanish, you might be more likely to say, "The vase broke," or, "The vase broke itself." If it's an accident, you wouldn't say that someone did it. In English, quite weirdly, we can even say things like, "I broke my arm." Now, in lots of languages, you couldn't use that construction unless you are a lunatic and you went out looking to break your arm and you succeeded. If it was an accident, you would use a different construction.
Now, this has consequences. So, people who speak different languages will pay attention to different things, depending on what their language usually requires them to do. So we show the same accident to English speakers and Spanish speakers, English speakers will remember who did it, because English requires you to say, "He did it; he broke the vase." Whereas Spanish speakers might be less likely to remember who did it if it's an accident, but they're more likely to remember that it was an accident. They're more likely to remember the intention. So, two people watch the same event, witness the same crime, but end up remembering different things about that event. This has implications, of course, for eyewitness testimony. It also has implications for blame and punishment. So if you take English speakers and I just show you someone breaking a vase, and I say, "He broke the vase," as opposed to "The vase broke," even though you can witness it yourself, you can watch the video, you can watch the crime against the vase, you will punish someone more, you will blame someone more if I just said, "He broke it," as opposed to, "It broke." The language guides our reasoning about events.
Now, I've given you a few examples of how language can profoundly shape the way we think, and it does so in a variety of ways. So language can have big effects, like we saw with space and time, where people can lay out space and time in completely different coordinate frames from each other. Language can also have really deep effects that's what we saw with the case of number. Having count words in your language, having number words, opens up the whole world of mathematics. Of course, if you don't count, you can't do algebra, you can't do any of the things that would be required to build a room like this or make this broadcast, right? This little trick of number words gives you a stepping stone into a whole cognitive realm.
Language can also have really early effects, what we saw in the case of color. These are really simple, basic, perceptual decisions. We make thousands of them all the time, and yet, language is getting in there and fussing even with these tiny little perceptual decisions that we make. Language can have really broad effects. So the case of grammatical gender may be a little silly, but at the same time, grammatical gender applies to all nouns. That means language can shape how you're thinking about anything that can be named by a noun. That's a lot of stuff.
And finally, I gave you an example of how language can shape things that have personal weight to us ideas like blame and punishment or eyewitness memory. These are important things in our daily lives.
Now, the beauty of linguistic diversity is that it reveals to us just how ingenious and how flexible the human mind is. Human minds have invented not one cognitive universe, but 7,000 there are 7,000 languages spoken around the world. And we can create many more languages, of course, are living things, things that we can hone and change to suit our needs. The tragic thing is that we're losing so much of this linguistic diversity all the time. We're losing about one language a week, and by some estimates, half of the world's languages will be gone in the next hundred years. And the even worse news is that right now, almost everything we know about the human mind and human brain is based on studies of usually American English-speaking undergraduates at universities. That excludes almost all humans. Right? So what we know about the human mind is actually incredibly narrow and biased, and our science has to do better.
I want to leave you with this final thought. I've told you about how speakers of different languages think differently, but of course, that's not about how people elsewhere think. It's about how you think. It's how the language that you speak shapes the way that you think. And that gives you the opportunity to ask, "Why do I think the way that I do?" "How could I think differently?" And also, "What thoughts do I wish to create?"
Thank you very much.
3 ways to make better decisions by thinking like a computer
If there's one city in the world where it's hard to find a place to buy or rent, it's Sydney. And if you've tried to find a home here recently, you're familiar with the problem. Every time you walk into an open house, you get some information about what's out there and what's on the market, but every time you walk out, you're running the risk of the very best place passing you by. So how do you know when to switch from looking to being ready to make an offer?
This is such a cruel and familiar problem that it might come as a surprise that it has a simple solution. 37 percent.
If you want to maximize the probability that you find the very best place, you should look at 37 percent of what's on the market, and then make an offer on the next place you see, which is better than anything that you've seen so far. Or if you're looking for a month, take 37 percent of that time 11 days, to set a standard and then you're ready to act.
We know this because trying to find a place to live is an example of an optimal stopping problem. A class of problems that has been studied extensively by mathematicians and computer scientists.
I'm a computational cognitive scientist. I spend my time trying to understand how it is that human minds work, from our amazing successes to our dismal failures. To do that, I think about the computational structure of the problems that arise in everyday life, and compare the ideal solutions to those problems to the way that we actually behave. As a side effect, I get to see how applying a little bit of computer science can make human decision-making easier. I have a personal motivation for this. Growing up in Perth as an overly cerebral kid ...
I would always try and act in the way that I thought was rational, reasoning through every decision, trying to figure out the very best action to take. But this is an approach that doesn't scale up when you start to run into the sorts of problems that arise in adult life. At one point, I even tried to break up with my girlfriend because trying to take into account her preferences as well as my own and then find perfect solutions was just leaving me exhausted. She pointed out that I was taking the wrong approach to solving this problem and she later became my wife.
Whether it's as basic as trying to decide what restaurant to go to or as important as trying to decide who to spend the rest of your life with, human lives are filled with computational problems that are just too hard to solve by applying sheer effort. For those problems, it's worth consulting the experts: computer scientists.
When you're looking for life advice, computer scientists probably aren't the first people you think to talk to. Living life like a computer stereotypically deterministic, exhaustive and exact doesn't sound like a lot of fun. But thinking about the computer science of human decisions reveals that in fact, we've got this backwards. When applied to the sorts of difficult problems that arise in human lives, the way that computers actually solve those problems looks a lot more like the way that people really act.
Take the example of trying to decide what restaurant to go to. This is a problem that has a particular computational structure. You've got a set of options, you're going to choose one of those options, and you're going to face exactly the same decision tomorrow. In that situation, you run up against what computer scientists call the "explore-exploit trade-off." You have to make a decision about whether you're going to try something new exploring, gathering some information that you might be able to use in the future or whether you're going to go to a place that you already know is pretty good exploiting the information that you've already gathered so far. The explore/exploit trade-off shows up any time you have to choose between trying something new and going with something that you already know is pretty good, whether it's listening to music or trying to decide who you're going to spend time with. It's also the problem that technology companies face when they're trying to do something like decide what ad to show on a web page. Should they show a new ad and learn something about it, or should they show you an ad that they already know there's a good chance you're going to click on?
Over the last 60 years, computer scientists have made a lot of progress understanding the explore/exploit trade-off, and their results offer some surprising insights. When you're trying to decide what restaurant to go to, the first question you should ask yourself is how much longer you're going to be in town. If you're just going to be there for a short time, then you should exploit. There's no point gathering information. Just go to a place you already know is good. But if you're going to be there for a longer time, explore. Try something new, because the information you get is something that can improve your choices in the future. The value of information increases the more opportunities you're going to have to use it.
This principle can give us insight into the structure of a human life as well. Babies don't have a reputation for being particularly rational. They're always trying new things, and you know, trying to stick them in their mouths. But in fact, this is exactly what they should be doing. They're in the explore phase of their lives, and some of those things could turn out to be delicious. At the other end of the spectrum, the old guy who always goes to the same restaurant and always eats the same thing isn't boring he's optimal.
He's exploiting the knowledge that he's earned through a lifetime's experience. More generally, knowing about the explore/exploit trade-off can make it a little easier for you to sort of relax and go easier on yourself when you're trying to make a decision. You don't have to go to the best restaurant every night. Take a chance, try something new, explore. You might learn something. And the information that you gain is going to be worth more than one pretty good dinner.
Computer science can also help to make it easier on us in other places at home and in the office. If you've ever had to tidy up your wardrobe, you've run into a particularly agonizing decision: you have to decide what things you're going to keep and what things you're going to give away. Martha Stewart turns out to have thought very hard about this
and she has some good advice. She says, "Ask yourself four questions: How long have I had it? Does it still function? Is it a duplicate of something that I already own? And when was the last time I wore it or used it?" But there's another group of experts who perhaps thought even harder about this problem, and they would say one of these questions is more important than the others. Those experts? The people who design the memory systems of computers. Most computers have two kinds of memory systems: a fast memory system, like a set of memory chips that has limited capacity, because those chips are expensive, and a slow memory system, which is much larger. In order for the computer to operate as efficiently as possible, you want to make sure that the pieces of information you want to access are in the fast memory system, so that you can get to them quickly. Each time you access a piece of information, it's loaded into the fast memory and the computer has to decide which item it has to remove from that memory, because it has limited capacity.
Over the years, computer scientists have tried a few different strategies for deciding what to remove from the fast memory. They've tried things like choosing something at random or applying what's called the "first-in, first-out principle," which means removing the item which has been in the memory for the longest. But the strategy that's most effective focuses on the items which have been least recently used. This says if you're going to decide to remove something from memory, you should take out the thing which was last accessed the furthest in the past. And there's a certain kind of logic to this. If it's been a long time since you last accessed that piece of information, it's probably going to be a long time before you're going to need to access it again. Your wardrobe is just like the computer's memory. You have limited capacity, and you need to try and get in there the things that you're most likely to need so that you can get to them as quickly as possible. Recognizing that, maybe it's worth applying the least recently used principle to organizing your wardrobe as well. So if we go back to Martha's four questions, the computer scientists would say that of these, the last one is the most important.
This idea of organizing things so that the things you are most likely to need are most accessible can also be applied in your office. The Japanese economist Yukio Noguchi actually invented a filing system that has exactly this property. He started with a cardboard box, and he put his documents into the box from the left-hand side. Each time he'd add a document, he'd move what was in there along and he'd add that document to the left-hand side of the box. And each time he accessed a document, he'd take it out, consult it and put it back in on the left-hand side. As a result, the documents would be ordered from left to right by how recently they had been used. And he found he could quickly find what he was looking for by starting at the left-hand side of the box and working his way to the right.
Before you dash home and implement this filing system it's worth recognizing that you probably already have. That pile of papers on your desk ... typically maligned as messy and disorganized, a pile of papers is, in fact, perfectly organized as long as you, when you take a paper out, put it back on the top of the pile, then those papers are going to be ordered from top to bottom by how recently they were used, and you can probably quickly find what you're looking for by starting at the top of the pile.
Organizing your wardrobe or your desk are probably not the most pressing problems in your life. Sometimes the problems we have to solve are simply very, very hard. But even in those cases, computer science can offer some strategies and perhaps some solace. The best algorithms are about doing what makes the most sense in the least amount of time. When computers face hard problems, they deal with them by making them into simpler problems by making use of randomness, by removing constraints or by allowing approximations. Solving those simpler problems can give you insight into the harder problems, and sometimes produces pretty good solutions in their own right.
Knowing all of this has helped me to relax when I have to make decisions. You could take the 37 percent rule for finding a home as an example. There's no way that you can consider all of the options, so you have to take a chance. And even if you follow the optimal strategy, you're not guaranteed a perfect outcome. If you follow the 37 percent rule, the probability that you find the very best place is funnily enough ... 37 percent. You fail most of the time. But that's the best that you can do.
Ultimately, computer science can help to make us more forgiving of our own limitations. You can't control outcomes, just processes. And as long as you've used the best process, you've done the best that you can. Sometimes those best processes involve taking a chance not considering all of your options, or being willing to settle for a pretty good solution. These aren't the concessions that we make when we can't be rational they're what being rational means.
Thank you.