Ted Transcripts

The four stories we tell ourselves about death by Stephen Cave I have a question: Who here remembers when they first realized they were going to die? I do. I was a young boy, and my grandfather had just died, and I remember a few days later lying in bed at night trying to make sense of what had happened. What did it mean that he was dead? Where had he gone? It was like a hole in reality had opened up and swallowed him. But then the really shocking question occurred to me: If he could die, could it happen to me too? Could that hole in reality open up and swallow me? Would it open up beneath my bed and swallow me as I slept? Well, at some point, all children become aware of death. It can happen in different ways, of course, and usually comes in stages. Our idea of death develops as we grow older. And if you reach back into the dark corners of your memory, you might remember something like what I felt when my grandfather died and when I realized it could happen to me too, that sense that behind all of this the void is waiting. And this development in childhood reflects the development of our species. Just as there was a point in your development as a child when your sense of self and of time became sophisticated enough for you to realize you were mortal, so at some point in the evolution of our species, some early human's sense of self and of time became sophisticated enough for them to become the first human to realize, "I'm going to die." This is, if you like, our curse. It's the price we pay for being so damn clever. We have to live in the knowledge that the worst thing that can possibly happen one day surely will, the end of all our projects, our hopes, our dreams, of our individual world. We each live in the shadow of a personal apocalypse.

And that's frightening. It's terrifying. And so we look for a way out. And in my case, as I was about five years old, this meant asking my mum. Now when I first started asking what happens when we die, the grownups around me at the time answered with a typical English mix of awkwardness and half-hearted Christianity, and the phrase I heard most often was that granddad was now "up there looking down on us," and if I should die too, which wouldn't happen of course, then I too would go up there, which made death sound a lot like an existential elevator. Now this didn't sound very plausible. I used to watch a children's news program at the time, and this was the era of space exploration. There were always rockets going up into the sky, up into space, going up there. But none of the astronauts when they came back ever mentioned having met my granddad or any other dead people. But I was scared, and the idea of taking the existential elevator to see my granddad sounded a lot better than being swallowed by the void while I slept. And so I believed it anyway, even though it didn't make much sense. And this thought process that I went through as a child, and have been through many times since, including as a grown-up, is a product of what psychologists call a bias. Now a bias is a way in which we systematically get things wrong, ways in which we miscalculate, misjudge, distort reality, or see what we want to see, and the bias I'm talking about works like this: Confront someone with the fact that they are going to die and they will believe just about any story that tells them it isn't true and they can, instead, live forever, even if it means taking the existential elevator. Now we can see this as the biggest bias of all. It has been demonstrated in over 400 empirical studies. Now these studies are ingenious, but they're simple. They work like this. You take two groups of people who are similar in all relevant respects, and you remind one group that they're going to die but not the other, then you compare their behavior. So you're observing how it biases behavior when people become aware of their mortality. And every time, you get the same result: People who are made aware of their mortality are more willing to believe stories that

tell them they can escape death and live forever. So here's an example: One recent study took two groups of agnostics, that is people who are undecided in their religious beliefs. Now, one group was asked to think about being dead. The other group was asked to think about being lonely. They were then asked again about their religious beliefs. Those who had been asked to think about being dead were afterwards twice as likely to express faith in God and Jesus. Twice as likely. Even though the before they were all equally agnostic. But put the fear of death in them, and they run to Jesus. Now, this shows that reminding people of death biases them to believe, regardless of the evidence, and it works not just for religion, but for any kind of belief system that promises immortality in some form, whether it's becoming famous or having children or even nationalism, which promises you can live on as part of a greater whole. This is a bias that has shaped the course of human history. Now, the theory behind this bias in the over 400 studies is called terror management theory, and the idea is simple. It's just this. We develop our worldviews, that is, the stories we tell ourselves about the world and our place in it, in order to help us manage the terror of death. And these immortality stories have thousands of different manifestations, but I believe that behind the apparent diversity there are actually just four basic forms that these immortality stories can take. And we can see them repeating themselves throughout history, just with slight variations to reflect the vocabulary of the day. Now I'm going to briefly introduce these four basic forms of immortality story, and I want to try to give you some sense of the way in which they're retold by each culture or generation using the vocabulary of their day. Now, the first story is the simplest. We want to avoid death, and the dream of doing that in this body in this world forever is the first and simplest kind of immortality story, and it might at first sound implausible, but actually, almost every culture in human history has had

some myth or legend of an elixir of life or a fountain of youth or something that promises to keep us going forever. Ancient Egypt had such myths, ancient Babylon, ancient India. Throughout European history, we find them in the work of the alchemists, and of course we still believe this today, only we tell this story using the vocabulary of science. So 100 years ago, hormones had just been discovered, and people hoped that hormone treatments were going to cure aging and disease, and now instead we set our hopes on stem cells, genetic engineering, and nanotechnology. But the idea that science can cure death is just one more chapter in the story of the magical elixir, a story that is as old as civilization. But betting everything on the idea of finding the elixir and staying alive forever is a risky strategy. When we look back through history at all those who have sought an elixir in the past, the one thing they now have in common is that they're all dead. So we need a backup plan, and exactly this kind of plan B is what the second kind of immortality story offers, and that's resurrection. And it stays with the idea that I am this body, I am this physical organism. It accepts that I'm going to have to die but says, despite that, I can rise up and I can live again. In other words, I can do what Jesus did. Jesus died, he was three days in the [tomb], and then he rose up and lived again. And the idea that we can all be resurrected to live again is orthodox believe, not just for Christians but also Jews and Muslims. But our desire to believe this story is so deeply embedded that we are reinventing it again for the scientific age, for example, with the idea of cryonics. That's the idea that when you die, you can have yourself frozen, and then, at some point when technology has advanced enough, you can be thawed out and repaired and revived and so resurrected. And so some people believe an omnipotent god will resurrect them to live again, and other people believe an omnipotent scientist will do it. But for others, the whole idea of resurrection, of climbing out of the grave, it's just too much like a bad zombie movie. They find the body too messy, too unreliable to guarantee eternal life, and so they set their

hopes on the third, more spiritual immortality story, the idea that we can leave our body behind and live on as a soul. Now, the majority of people on Earth believe they have a soul, and the idea is central to many religions. But even though, in its current form, in its traditional form, the idea of the soul is still hugely popular, nonetheless we are again reinventing it for the digital age, for example with the idea that you can leave your body behind by uploading your mind, your essence, the real you, onto a computer, and so live on as an avatar in the ether. But of course there are skeptics who say if we look at the evidence of science, particularly neuroscience, it suggests that your mind, your essence, the real you, is very much dependent on a particular part of your body, that is, your brain. And such skeptics can find comfort in the fourth kind of immortality story, and that is legacy, the idea that you can live on through the echo you leave in the world, like the great Greek warrior Achilles, who sacrificed his life fighting at Troy so that he might win immortal fame. And the pursuit of fame is as widespread and popular now as it ever was, and in our digital age, it's even easier to achieve. You don't need to be a great warrior like Achilles or a great king or hero. All you need is an Internet connection and a funny cat. (Laughter) But some people prefer to leave a more tangible, biological legacy -- children, for example. Or they like, they hope, to live on as part of some greater whole, a nation or a family or a tribe, their gene pool. But again, there are skeptics who doubt whether legacy really is immortality. Woody Allen, for example, who said, "I don't want to live on in the hearts of my countrymen. I want to live on in my apartment." So those are the four basic kinds of immortality stories, and I've tried to give just some sense of how they're retold by each generation with just slight variations to fit the fashions of the day. And the fact that they recur in this way, in such a similar form but in such different belief systems, suggests, I think, that we should be skeptical of the truth of any particular version of these stories. The fact that some people believe an omnipotent god will resurrect them to live again and others believe an

omnipotent scientist will do it suggests that neither are really believing this on the strength of the evidence. Rather, we believe these stories because we are biased to believe them, and we are biased to believe them because we are so afraid of death. So the question is, are we doomed to lead the one life we have in a way that is shaped by fear and denial, or can we overcome this bias? Well the Greek philosopher Epicurus thought we could. He argued that the fear of death is natural, but it is not rational. "Death," he said, "is nothing to us, because when we are here, death is not, and when death is here, we are gone." Now this is often quoted, but it's difficult to really grasp, to really internalize, because exactly this idea of being gone is so difficult to imagine. So 2,000 years later, another philosopher, Ludwig Wittgenstein, put it like this: "Death is not an event in life: We do not live to experience death. And so," he added, "in this sense, life has no end." So it was natural for me as a child to fear being swallowed by the void, but it wasn't rational, because being swallowed by the void is not something that any of us will ever live to experience. Now, overcoming this bias is not easy because the fear of death is so deeply embedded in us, yet when we see that the fear itself is not rational, and when we bring out into the open the ways in which it can unconsciously bias us, then we can at least start to try to minimize the influence it has on our lives. Now, I find it helps to see life as being like a book: Just as a book is bounded by its covers, by beginning and end, so our lives are bounded by birth and death, and even though a book is limited by beginning and end, it can encompass distant landscapes, exotic figures, fantastic adventures. And even though a book is limited by beginning and end, the characters within it know no horizons. They only know the moments that make up their story, even when the book is closed. And so the characters of a book are not afraid of reaching the last page. Long

John Silver is not afraid of you finishing your copy of "Treasure Island." And so it should be with us. Imagine the book of your life, its covers, its beginning and end, and your birth and your death. You can only know the moments in between, the moments that make up your life. It makes no sense for you to fear what is outside of those covers, whether before your birth or after your death. And you needn't worry how long the book is, or whether it's a comic strip or an epic. The only thing that matters is that you make it a good story.

What is so special about the human brain by Suzana Herculano-Houzel What is so special about the human brain? Why is it that we study other animals instead of them studying us? What does a human brain have or do that no other brain does? When I became interested in these questions about 10 years ago, scientists thought they knew what different brains were made of. Though it was based on very little evidence, many scientists thought that all mammalian brains, including the human brain, were made in the same way, with a number of neurons that was always proportional to the size of the brain. This means that two brains of the same size, like these two, with a respectable 400 grams, should have similar numbers of neurons. Now, if neurons are the functional information processing units of the brain, then the owners of these two brains should have similar cognitive abilities. And yet, one is a chimp, and the other is a cow. Now maybe cows have a really rich internal mental life and are so smart that they choose not to let us realize it, but we eat them. I think most people will agree that chimps are capable of much more complex, elaborate and flexible behaviors than cows are. So this is a first indication that the "all brains are made the same way" scenario is not quite right. But let's play along. If all brains were made the same way and you were to compare animals with brains of different sizes, larger brains should always have more neurons than smaller brains, and the larger the brain,

the more cognitively able its owner should be. So the largest brain around should also be the most cognitively able. And here comes the bad news: Our brain, not the largest one around. It seems quite vexing. Our brain weighs between 1.2 and 1.5 kilos, but elephant brains weigh between four and five kilos, and whale brains can weigh up to nine kilos, which is why scientists used to resort to saying that our brain must be special to explain our cognitive abilities. It must be really extraordinary, an exception to the rule. Theirs may be bigger, but ours is better, and it could be better, for example, in that it seems larger than it should be, with a much larger cerebral cortex than we should have for the size of our bodies. So that would give us extra cortex to do more interesting things than just operating the body. That's because the size of the brain usually follows the size of the body. So the main reason for saying that our brain is larger than it should be actually comes from comparing ourselves to great apes. Gorillas can be two to three times larger than we are, so their brains should also be larger than ours, but instead it's the other way around. Our brain is three times larger than a gorilla brain. The human brain also seems special in the amount of energy that it uses. Although it weighs only two percent of the body, it alone uses 25 percent of all the energy that your body requires to run per day. That's 500 calories out of a total of 2,000 calories, just to keep your brain working. So the human brain is larger than it should be, it uses much more energy than it should, so it's special. And this is where the story started to bother me. In biology, we look for rules that apply to all animals and to life in general, so why should the rules of evolution apply to everybody else but not to us? Maybe the problem was with the basic assumption that all brains are made in the same way. Maybe two brains of a similar size can actually be made of very different numbers of neurons. Maybe a very large brain does not necessarily have more neurons than a more modest-sized brain. Maybe the human brain actually has the most neurons of any brain, regardless of its size, especially in the cerebral cortex. So this to me became the important question to answer: how many neurons does the human brain have, and how does that compare to other animals?

Now, you may have heard or read somewhere that we have 100 billion neurons, so 10 years ago, I asked my colleagues if they knew where this number came from. But nobody did. I've been digging through the literature for the original reference for that number, and I could never find it. It seems that nobody had actually ever counted the number of neurons in the human brain, or in any other brain for that matter. So I came up with my own way to count cells in the brain, and it essentially consists of dissolving that brain into soup. It works like this: You take a brain, or parts of that brain, and you dissolve it in detergent, which destroys the cell membranes but keeps the cell nuclei intact, so you end up with a suspension of free nuclei that looks like this, like a clear soup. This soup contains all the nuclei that once were a mouse brain. Now, the beauty of a soup is that because it is soup, you can agitate it and make those nuclei be distributed homogeneously in the liquid, so that now by looking under the microscope at just four or five samples of this homogeneous solution, you can count nuclei, and therefore tell how many cells that brain had. It's simple, it's straightforward, and it's really fast. So we've used that method to count neurons in dozens of different species so far, and it turns out that all brains are not made the same way. Take rodents and primates, for instance: In larger rodent brains, the average size of the neuron increases, so the brain inflates very rapidly and gains size much faster than it gains neurons. But primate brains gain neurons without the average neuron becoming any larger, which is a very economical way to add neurons to your brain. The result is that a primate brain will always have more neurons than a rodent brain of the same size, and the larger the brain, the larger this difference will be. Well, what about our brain then? We found that we have, on average, 86 billion neurons, 16 billion of which are in the cerebral cortex, and if you consider that the cerebral cortex is the seat of functions like awareness and logical and abstract reasoning, and that 16 billion is the most neurons that any cortex has, I think this is the simplest explanation for our remarkable cognitive abilities. But just as important is what the 86 billion neurons mean. Because we found that the relationship between the size of the brain and its number of neurons could be described mathematically, we could calculate what a human brain would look like if it was made like a rodent brain. So, a rodent brain with 86 billion neurons would weigh 36

kilos. That's not possible. A brain that huge would be crushed by its own weight, and this impossible brain would go in the body of 89 tons. I don't think it looks like us. So this brings us to a very important conclusion already, which is that we are not rodents. The human brain is not a large rat brain. Compared to a rat, we might seem special, yes, but that's not a fair comparison to make, given that we know that we are not rodents. We are primates, so the correct comparison is to other primates. And there, if you do the math, you find that a generic primate with 86 billion neurons would have a brain of about 1.2 kilos, which seems just right, in a body of some 66 kilos, which in my case is exactly right, which brings us to a very unsurprising but still incredibly important conclusion: I am a primate. And all of you are primates. And so was Darwin. I love to think that Darwin would have really appreciated this. His brain, like ours, was made in the image of other primate brains. So the human brain may be remarkable, yes, but it is not special in its number of neurons. It is just a large primate brain. I think that's a very humbling and sobering thought that should remind us of our place in nature. Why does it cost so much energy, then? Well, other people have figured out how much energy the human brain and that of other species costs, and now that we knew how many neurons each brain was made of, we could do the math. And it turns out that both human and other brains cost about the same, an average of six calories per billion neurons per day. So the total energetic cost of a brain is a simple, linear function of its number of neurons, and it turns out that the human brain costs just as much energy as you would expect. So the reason why the human brain costs so much energy is simply because it has a huge number of neurons, and because we are primates with many more neurons for a given body size than any other animal, the relative cost of our brain is large, but just because we're primates, not because we're special.

Last question, then: how did we come by this remarkable number of neurons, and in particular, if great apes are larger than we are, why don't they have a larger brain than we do, with more neurons? When we realized how much expensive it is to have a lot of neurons in the brain, I figured, maybe there's a simple reason. They just can't afford the energy for both a large body and a large number of neurons. So we did the math. We calculated on the one hand how much energy a primate gets per day from eating raw foods, and on the other hand, how much energy a body of a certain size costs and how much energy a brain of a certain number of neurons costs, and we looked for the combinations of body size and number of brain neurons that a primate could afford if it ate a certain number of hours per day. And what we found is that because neurons are so expensive, there is a tradeoff between body size and number of neurons. So a primate that eats eight hours per day can afford at most 53 billion neurons, but then its body cannot be any bigger than 25 kilos. To weigh any more than that, it has to give up neurons. So it's either a large body or a large number of neurons. When you eat like a primate, you can't afford both. One way out of this metabolic limitation would be to spend even more hours per day eating, but that gets dangerous, and past a certain point, it's just not possible. Gorillas and orangutans, for instance, afford about 30 billion neurons by spending eight and a half hours per day eating, and that seems to be about as much as they can do. Nine hours of feeding per day seems to be the practical limit for a primate. What about us? With our 86 billion neurons and 60 to 70 kilos of body mass, we should have to spend over nine hours per day every single day feeding, which is just not feasible. If we ate like a primate, we should not be here. How did we get here, then? Well, if our brain costs just as much energy as it should, and if we can't spend every waking hour of the day feeding, then the only alternative, really, is to somehow get more energy out of the same foods. And remarkably, that matches exactly what our ancestors are believed to have invented one and a half million years ago, when they invented cooking. To cook is to use fire to pre-digest foods

outside of your body. Cooked foods are softer, so they're easier to chew and to turn completely into mush in your mouth, so that allows them to be completely digested and absorbed in your gut, which makes them yield much more energy in much less time. So cooking frees time for us to do much more interesting things with our day and with our neurons than just thinking about food, looking for food, and gobbling down food all day long. So because of cooking, what once was a major liability, this large, dangerously expensive brain with a lot of neurons, could now become a major asset, now that we could both afford the energy for a lot of neurons and the time to do interesting things with them. So I think this explains why the human brain grew to become so large so fast in evolution, all of the while remaining just a primate brain. With this large brain now affordable by cooking, we went rapidly from raw foods to culture, agriculture, civilization, grocery stores, electricity, refrigerators, all of those things that nowadays allow us to get all the energy we need for the whole day in a single sitting at your favorite fast food joint. So what once was a solution now became the problem, and ironically, we look for the solution in raw food. So what is the human advantage? What is it that we have that no other animal has? My answer is that we have the largest number of neurons in the cerebral cortex, and I think that's the simplest explanation for our remarkable cognitive abilities. And what is it that we do that no other animal does, and which I believe was fundamental to allow us to reach that large, largest number of neurons in the cortex? In two words, we cook. No other animal cooks its food. Only humans do. And I think that's how we got to become human. Studying the human brain changed the way I think about food. I now look at my kitchen, and I bow to it, and I thank my ancestors for coming up with the invention that probably made us humans. Thank you very much. (Applause)

Ingenuity and elegance in ancient African alphabets By Saki Mafundikwa I moved back home 15 years ago after a 20-year stay in the United States, and Africa called me back. And I founded my country's first graphic design and new media college. And I called it the Zimbabwe Institute of Vigital Arts. The idea, the dream, was really for a sort of Bauhaus sort of school where new ideas were interrogated and investigated, the creation of a new visual language based on the African creative heritage. We offer a two-year diploma to talented students who have successfully completed their high school education. And typography's a very important part of the curriculum and we encourage our students to look inward for influence. Here's a poster designed by one of the students under the theme "Education is a right." Some logos designed by my students. Africa has had a long tradition of writing, but this is not such a wellknown fact, and I wrote the book "Afrikan Alphabets" to address that. The different types of writing in Africa, first was proto-writing, as illustrated by Nsibidi, which is the writing system of a secret society of the Ejagham people in southern Nigeria. So it's a special-interest writing system. The Akan of people of Ghana and [Cote d'Ivoire] developed Adinkra symbols some 400 years ago, and these are proverbs, historical sayings, objects, animals, plants, and my favorite Adinkra system is the first one at the top on the left. It's called Sankofa. It means, "Return and get it." Learn from the past. This pictograph by the Jokwe people of Angola tells the story of the creation of the world. At the top is God, at the bottom is man, mankind, and on the left is the sun, on the right is the moon. All the paths lead to and from God. These secret societies of the Yoruba, Kongo and Palo religions in Nigeria, Congo and Angola respectively, developed this intricate writing system which is alive and well today in the New World in Cuba, Brazil and Trinidad and Haiti. In the rainforests of the Democratic Republic of Congo, in the Ituri society, the men pound out a cloth out of a special tree, and the women, who are also the praise singers, paint interweaving patterns that are the same in structure as the polyphonic structures that they use in their

singing -- a sort of a musical score, if you may. In South Africa, Ndebele women use these symbols and other geometric patterns to paint their homes in bright colors, and the Zulu women use the symbols in the beads that they weave into bracelets and necklaces. Ethiopia has had the longest tradition of writing, with the Ethiopic script that was developed in the fourth century A.D. and is used to write Amharic, which is spoken by over 24 million people. King Ibrahim Njoya of the Bamum Kingdom of Cameroon developed Shü-mom at the age of 25. Shü-mom is a writing system. It's a syllabary. It's not exactly an alphabet. And here we see three stages of development that it went through in 30 years. The Vai people of Liberia had a long tradition of literacy before their first contact with Europeans in the 1800s. It's a syllabary and reads from left to right. Next door, in Sierra Leone, the Mende also developed a syllabary, but theirs reads from right to left. Africa has had a long tradition of design, a well-defined design sensibility, but the problem in Africa has been that, especially today, designers in Africa struggle with all forms of design because they are more apt to look outward for influence and inspiration. The creative spirit in Africa, the creative tradition, is as potent as it has always been, if only designers could look within. This Ethiopic cross illustrates what Dr. Ron Eglash has established: that Africa has a lot to contribute to computing and mathematics through their intuitive grasp of fractals. Africans of antiquity created civilization, and their monuments, which still stand today, are a true testimony of their greatness. Most probably, one of humanity's greatest achievements is the invention of the alphabet, and that has been attributed to Mesopotamia with their invention of cuneiform in 1600 BC, followed by hieroglyphics in Egypt, and that story has been cast in stone as historical fact. That is, until 1998, when one Yale professor John Coleman Darnell discovered these inscriptions in the Thebes desert on the limestone cliffs in western Egypt, and these have been dated at between 1800 and 1900 B.C., centuries before Mesopotamia. Called Wadi el-Hol because of the place that they were discovered, these inscriptions -- research is still going on, a few of them have been deciphered, but there is consensus among scholars that this is really humanity's first alphabet. Over here, you see a

paleographic chart that shows what has been deciphered so far, starting with the letter A, "ālep," at the top, and "bêt," in the middle, and so forth. It is time that students of design in Africa read the works of titans like Cheikh Anta Diop, Senegal's Cheikh Anta Diop, whose seminal work on Egypt is vindicated by this discovery. The last word goes to the great Jamaican leader Marcus Mosiah Garvey and the Akan people of Ghana with their Adinkra symbol Sankofa, which encourages us to go to the past so as to inform our present and build on a future for us and our children. It is also time that designers in Africa stop looking outside. They've been looking outward for a long time, yet what they were looking for has been right there within grasp, right within them. Thank you very much. (Applause) Fix your bad English Hi. James, from EngVid. Today's video is on, well, "The Book of Bad English". There are mistakes that native speakers make that ESL people pick up -- and "ESL" is "English as a Second Language". People learning English, they pick up because native speakers don't even know they're making this mistake. So I want to teach you six common ones that come regularly or happen regularly in conversation. And I want you to learn them and make your English perfect. Let's go to the board. Now, let's start with No. 1, one of my favorite ones: "amount" and "number". "Amount" is, sort of, like, "how much". A "number" is, you know, "thing". When we look at "amount", you can think of you can't count it, all right? A lot of times, when we say "amount" -- like, "I have a large amount of water in my house" -- you can't count water. But you can count a number, so: "The number of people who come to the city is in the thousands", so you can count them. Here's an example. Tell me if this is right or wrong. "The amount of students who are late is growing every day" or "the number of students who are late is growing every day." You should say "number" because you can count students. You can't count amount. That rhymes. Maybe that'll help, right? You can't count amount. You can't count amount. So when we want to talk about

a number of something or a body of something, "amount" is for things you cannot count, and "number" is for things you can count. English people make this mistake a lot. Next: "among" and "between". When I used to teach "among" and "between", I would say, "'Among' is 'with'. So there're five chairs, and you're 'with' another. And 'between' is you're in the middle." That's it. Because I was so smart. And then I found out it's just this: two. More than two. That's it. Nothing special. When you talk about "between", except -- and this is a major exception -- when you're talking about differences. Differences you have to use "between". But generally speaking, "among" is more than two. "I was sitting among my friends at the bar." You can know there're probably four or five, not two. But "let's keep this between you and me"? A lot of times, Canadians say, "Let's keep this among us." And it's like, "Among who?" "The rest of those guys, you know. The Americans. They don't need to know this." Okay. So "between us" -- usually two, right? It could be two groups. "There was a fight between this country and that country." Right? Because it's two groups. But "among" is for more than two, cool? All right. So "among" -more than two; "between" -- two. What about "bring" and "take"? This is something that a lot of students make a mistake on. So you say, "Bring this to me" or "take this to him." It's very easy. "Bring" is "to the speaker", okay? And "take" is "away from the speaker". Now, if you're born in England, that's easy because they always talk about "I want takeaway." Takeaway. Because they take the food away from the restaurant, right? So one of my favorite sayings that we say in England -- not England -- that we say here is, like -- watch every space movie: "Take me to your leader." You'll never see a space movie, unless it's made by me -- and it would say, "Bring me to your leader." We don't do that. You say, "Take them to the leader" because you're taking them away from this spot where the speaker is to a new location or spot. So "take" and "bring" are easy because it's "bring -come towards". Here's a mistake -- not Canadians -- English speakers make that you should be aware of. They'll say something like, "Don't forget to bring your bag with you" instead of, "Don't forget to take your bag." Do you know what the difference is? Well, you're leaving, right? So you need to take it away. Remember I said "away from"? Take the bag away from you. When you say, "Bring the bag with you", the speaker's speaking, you're still moving away from the speaker, right? So you've got

to use this. But Canadians and Americans and Brits say it a lot. They'll say, "Bring it with you." No. "Take" it with you. You know the difference now because you're smart. And you're studying from The Book of Bad English. Good for you. There's a worm in that book. Watch it. Okay. "Fewer" or "less". I'm going to make a statement, and think which one is correct. "'Fewer' than a million people have watched the videos on EngVid. 'Less' than a million people have watched the videos on EngVid." Which one would be correct? Yeah. If you said "less than", no. "Less" is similar to "amount". You say "fewer" for things you can count. The birds and the bees are just the beginning By Carin Bondar Anyone in the room thought about sex today? (Laughter) Yeah, you did. Thank you for putting your hand up over there. Well, I'm here to provide you with some biological validation for your sordid daydreams. I'm here to tell you a few things that you might not have known about wild sex. Now, when humans think about sex, male and female forms are generally what come to mind, but for many millions of years, such specific categories didn't even exist. Sex was a mere fusion of bodies or a trickle of DNA shared between two or more beings. It wasn't until about 500 million years ago that we start to see structures akin to a penis or a thing that gives DNA out, and a vagina, something that receives it. Now invariably, you're probably thinking about what belongs to our own species, these very familiar structures, but the diversity that we see in sexual structures in the animal kingdom that has evolved in response to the multitude of factors surrounding reproduction is pretty mindblowing. Penile diversity is especially profuse. So this is a paper nautilus. It's a close relative of squid and octopus, and males have a hectocotylus. Just what is a hectocotylus? A detachable, swimming penis. It leaves the [body of the male], finds the female through pheromonal cues in the water, attaches itself to her body and deposits the sperm. For many decades, biologists actually felt that the hectocotylus was a separate

organism altogether. Now, the tapir is a mammal from South America. And the tapir has a prehensile penis. It actually has a level of dexterity in its penis much akin to what we have with our hands. And it uses this dexterity to bypass the vagina altogether and deposit sperm directly into the female's uterus, not to mention it's a pretty good size. The biggest penis in the animal kingdom, however, is not that of the tapir. The biggest penis-to-body-size ratio in the animal kingdom actually belongs to the meager beach barnacle, and this video is actually showing you what the human penis would look like if it were the same size as that of a barnacle. (Laughter) Mm-hm. (Laughter) So with all of this diversity in structure, one might think, then, that penises are fitting neatly into vaginas all over the place for the purposes of successful reproduction. Simply insert part A into slot B, and we should all be good to go. But of course, that doesn't exactly happen, and that's because we can't just take form into account. We have to think about function as well, and when it comes to sex, function relates to the contributions made by the gametes, or the sperm and the eggs. And these contributions are far from equal. Eggs are very expensive to make, so it makes sense for females to be very choosy about who she shares them with. Sperm, on the other hand, is abundant and cheap, so it makes more sense for males to have a more-sex-is-better strategy when it comes to siring members of future generations. So how do animals cope with these very incongruent needs between the sexes? I mean, if a female doesn't choose a particular male, or if she has the ability to store sperm and she simply has enough, then it makes more sense for her to spend her time doing other biologically relevant things: avoiding predators, taking care of offspring, gathering and ingesting food. This is, of course, bad news for any male who has yet to make a deposit in her sperm bank, and this sets the scene for some pretty drastic strategies for successful fertilization. This is bedbug sex, and it's aptly termed traumatic insemination. Males have a spiked, barbed penis that they literally stab into the female, and they don't stab it anywhere near her vagina. They stab it anywhere in her body, and the sperm simply migrates through her hemolymph to her ovaries. If a female gets too many stab wounds, or if a stab wound happens to become infected, she can actually die from it.

Now if you've ever been out for a nice, peaceful walk by the lake and happened to see some ducks having sex, you've undoubtedly been alarmed, because it looks like gang rape. And quite frankly, that's exactly what it is. A group of males will grab a female, hold her down, and ballistically ejaculate their spiral-shaped penis into her corkscrewshaped vagina over and over and over again. From flaccid to ejaculation in less than a second. Now the female actually gets the last laugh, though, because she can actually manipulate her posture so as to allow the sperm of certain suitors better access to her ovaries. Now, I like to share stories like this with my audiences because, yeah, we humans, we tend to think sex, sex is fun, sex is good, there's romance, and there's orgasm. But orgasm didn't actually evolve until about 65 million years ago with the advent of mammals. But some animals had it going on quite a bit before that. There are some more primitive ways of pleasing one's partner. Earwig males have either really large penile appendages or really small ones. It's a very simple genetically inherited trait and the males are not otherwise any different. Those that have long penile appendages are not bigger or stronger or otherwise any different at all. So going back to our biological minds, then, we might think that females should choose to have sex with the guys that have the shorter appendages, because she can use her time for other things: avoiding predators, taking care of young, finding and ingesting food. But biologists have repeatedly observed that females choose to have sex with the males that have the long appendages. Why do they do this? Well, according to the biological literature, "During copulation, the genitalia of certain males may elicit more favorable female responses through superior mechanical or stimulatory interaction with the female reproductive tract." Mm-hm. These are Mexican guppies, and what you see on their upper maxilla is an outgrowth of epidermal filaments, and these filaments basically form a fish mustache, if you will. Now males have been observed to prod the female's genital opening prior to copulating with her, and in what I have lovingly termed the Magnum, P.I. hypothesis, females are

overwhelmingly more likely to be found with males that have these fish mustaches. A little guppy porn for you right there. So we've seen very different strategies that males are using when it comes to winning a female partner. We've seen a coercion strategy in which sexual structures are used in a forceful way to basically make a female have sex. We've also seen a titillation strategy where males are actually pleasing their female partners into choosing them as a sex partner. Now unfortunately, in the animal kingdom, it's the coercion strategy that we see time and time again. It's very common in many phyla, from invertebrates to avian species, mammals, and, of course, even in primates. Now interestingly, there are a few mammalian species in which females have evolved specialized genitalia that doesn't allow for sexual coercion to take place. Female elephants and female hyenas have a penile clitoris, or an enlarged clitoral tissue that hangs externally, much like a penis, and in fact it's very difficult to sex these animals by merely looking at their external morphology. So before a male can insert his penis into a female's vagina, she has to take this penile clitoris and basically insideout it in her own body. I mean, imagine putting a penis into another penis. It's simply not going to happen unless the female is on board with the action. Now, even more interesting is the fact that elephant and hyena societies are entirely matriarchal: they're run by females, groups of females, sisters, aunts and offspring, and when young males attain sexual maturity, they're turfed out of the group. In hyena societies, adult males are actually the lowest on the social scale. They can take part in a kill only after everybody else, including the offspring. So it seems that when you take the penis power away from a male, you take away all the social power he has. So what are my take-home messages from my talk today? Well, sex is just so much more than insert part A into slot B and hope that the offspring run around everywhere. The sexual strategies and reproductive structures that we see in the animal kingdom basically dictate how males and females will react to each other, which then dictates how populations and societies form and evolve.

So it may not be surprising to any of you that animals, including ourselves, spend a good amount of time thinking about sex, but what might surprise you is the extent to which so many other aspects of their lives and our lives are influenced by it. So thank you, and happy daydreaming. (Applause)

Why I must come out By Geena Rocero The world makes you something that you're not, but you know inside what you are, and that question burns in your heart: How will you become that? I may be somewhat unique in this, but I am not alone, not alone at all. So when I became a fashion model, I felt that I'd finally achieved the dream that I'd always wanted since I was a young child. My outside self finally matched my inner truth, my inner self. For complicated reasons which I'll get to later, when I look at this picture, at that time I felt like, Geena, you've done it, you've made it, you have arrived. But this past October, I realized that I'm only just beginning. All of us are put in boxes by our family, by our religion, by our society, our moment in history, even our own bodies. Some people have the courage to break free, not to accept the limitations imposed by the color of their skin or by the beliefs of those that surround them. Those people are always the threat to the status quo, to what is considered acceptable. In my case, for the last nine years, some of my neighbors, some of my friends, colleagues, even my agent, did not know about my history. I think, in mystery, this is called the reveal. Here is mine. I was assigned boy at birth based on the appearance of my genitalia. I remember when I was five years old in the Philippines walking around our house, I would always wear this t-shirt on my head. And my mom asked me, "How come you always wear that t-shirt on your head?" I said, "Mom, this is my hair. I'm a girl." I knew then how to self-identify.

Gender has always been considered a fact, immutable, but we now know it's actually more fluid, complex and mysterious. Because of my success, I never had the courage to share my story, not because I thought what I am is wrong, but because of how the world treats those of us who wish to break free. Every day, I am so grateful because I am a woman. I have a mom and dad and family who accepted me for who I am. Many are not so fortunate. There's a long tradition in Asian culture that celebrates the fluid mystery of gender. There is a Buddhist goddess of compassion. There is a Hindu goddess, hijra goddess. So when I was eight years old, I was at a fiesta in the Philippines celebrating these mysteries. I was in front of the stage, and I remember, out comes this beautiful woman right in front of me, and I remember that moment something hit me: That is the kind of woman I would like to be. So when I was 15 years old, still dressing as a boy, I met this woman named T.L. She is a transgender beauty pageant manager. That night she asked me, "How come you are not joining the beauty pageant?" She convinced me that if I joined that she would take care of the registration fee and the garments, and that night, I won best in swimsuit and best in long gown and placed second runner up among 40-plus candidates. That moment changed my life. All of a sudden, I was introduced to the world of beauty pageants. Not a lot of people could say that your first job is a pageant queen for transgender women, but I'll take it. So from 15 to 17 years old, I joined the most prestigious pageant to the pageant where it's at the back of the truck, literally, or sometimes it would be a pavement next to a rice field, and when it rains -- it rains a lot in the Philippines -- the organizers would have to move it inside someone's house. I also experienced the goodness of strangers, especially when we would travel in remote provinces in the Philippines. But most importantly, I met some of my best friends in that community. In 2001, my mom, who had moved to San Francisco, called me and told me that my green card petition came through, that I could now move to the United States. I resisted it. I told my mom, "Mom, I'm having fun. I'm here with my friends, I love traveling, being a beauty pageant

queen." But then two weeks later she called me, she said, "Did you know that if you move to the United States you could change your name and gender marker?" That was all I needed to hear. My mom also told me to put two E's in the spelling of my name. She also came with me when I had my surgery in Thailand at 19 years old. It's interesting, in some of the most rural cities in Thailand, they perform some of the most prestigious, safe and sophisticated surgery. At that time in the United States, you needed to have surgery before you could change your name and gender marker. So in 2001, I moved to San Francisco, and I remember looking at my California driver's license with the name Geena and gender marker F. That was a powerful moment. For some people, their I.D. is their license to drive or even to get a drink, but for me, that was my license to live, to feel dignified. All of a sudden, my fears were minimized. I felt that I could conquer my dream and move to New York and be a model. Many are not so fortunate. I think of this woman named Ayla Nettles. She's from New York, she's a young woman who was courageously living her truth, but hatred ended her life. For most of my community, this is the reality in which we live. Our suicide rate is nine times higher than that of the general population. Every November 20, we have a global vigil for Transgender Day of Remembrance. I'm here at this stage because it's a long history of people who fought and stood up for injustice. This is Marsha P. Johnson and Sylvia Rivera. Today, this very moment, is my real coming out. I could no longer live my truth for and by myself. I want to do my best to help others live their truth without shame and terror. I am here, exposed, so that one day there will never be a need for a November 20 vigil. My deepest truth allowed me to accept who I am. Will you? Thank you very much. (Applause) Thank you. Thank you. Thank you. (Applause) Kathryn Schulz: Geena, one quick question for you. I'm wondering what you would say, especially to parents, but in a more broad way, to friends, to family, to anyone who finds themselves encountering a child or a

person who is struggling with and uncomfortable with a gender that's being assigned them, what might you say to the family members of that person to help them become good and caring and kind family members to them? Geena Rocero: Sure. Well, first, really, I'm so blessed. The support system, with my mom especially, and my family, that in itself is just so powerful. I remember every time I would coach young trans women, I would mentor them, and sometimes when they would call me and tell me that their parents can't accept it, I would pick up that phone call and tell my mom, "Mom, can you call this woman?" And sometimes it works, sometimes it doesn't, so — But it's just, gender identity is in the core of our being, right? I mean, we're all assigned gender at birth, so what I'm trying to do is to have this conversation that sometimes that gender assignment doesn't match, and there should be a space that would allow people to self-identify, and that's a conversation that we should have with parents, with colleagues. The transgender movement, it's at the very beginning, to compare to how the gay movement started. There's still a lot of work that needs to be done. There should be an understanding. There should be a space of curiosity and asking questions, and I hope all of you guys will be my allies. KS: Thank you. That was so lovely. GR: Thank you. (Applause) A word game to communicate in any language By Ajit Narayanan I work with children with autism. Specifically, I make technologies to help them communicate. Now, many of the problems that children with autism face, they have a common source, and that source is that they find it difficult to understand abstraction, symbolism. And because of this, they have a lot of difficulty with language.

Let me tell you a little bit about why this is. You see that this is a picture of a bowl of soup. All of us can see it. All of us understand this. These are two other pictures of soup, but you can see that these are more abstract These are not quite as concrete. And when you get to language, you see that it becomes a word whose look, the way it looks and the way it sounds, has absolutely nothing to do with what it started with, or what it represents, which is the bowl of soup. So it's essentially a completely abstract, a completely arbitrary representation of something which is in the real world, and this is something that children with autism have an incredible amount of difficulty with. Now that's why most of the people that work with children with autism -- speech therapists, educators -what they do is, they try to help children with autism communicate not with words, but with pictures. So if a child with autism wanted to say, "I want soup," that child would pick three different pictures, "I," "want," and "soup," and they would put these together, and then the therapist or the parent would understand that this is what the kid wants to say. And this has been incredibly effective; for the last 30, 40 years people have been doing this. In fact, a few years back, I developed an app for the iPad which does exactly this. It's called Avaz, and the way it works is that kids select different pictures. These pictures are sequenced together to form sentences, and these sentences are spoken out. So Avaz is essentially converting pictures, it's a translator, it converts pictures into speech. Now, this was very effective. There are thousands of children using this, you know, all over the world, and I started thinking about what it does and what it doesn't do. And I realized something interesting: Avaz helps children with autism learn words. What it doesn't help them do is to learn word patterns. Let me explain this in a little more detail. Take this sentence: "I want soup tonight." Now it's not just the words here that convey the meaning. It's also the way in which these words are arranged, the way these words are modified and arranged. And that's why a sentence like "I want soup tonight" is different from a sentence like "Soup want I tonight," which is completely meaningless. So there is another hidden abstraction here which children with autism find a lot of difficulty coping with, and that's the fact that you can modify words and you can arrange them to have different meanings, to convey different ideas. Now, this is what we call grammar. And grammar is incredibly powerful, because grammar is this one component of language which

takes this finite vocabulary that all of us have and allows us to convey an infinite amount of information, an infinite amount of ideas. It's the way in which you can put things together in order to convey anything you want to. And so after I developed Avaz, I worried for a very long time about how I could give grammar to children with autism. The solution came to me from a very interesting perspective. I happened to chance upon a child with autism conversing with her mom, and this is what happened. Completely out of the blue, very spontaneously, the child got up and said, "Eat." Now what was interesting was the way in which the mom was trying to tease out the meaning of what the child wanted to say by talking to her in questions. So she asked, "Eat what? Do you want to eat ice cream? You want to eat? Somebody else wants to eat? You want to eat cream now? You want to eat ice cream in the evening?" And then it struck me that what the mother had done was something incredible. She had been able to get that child to communicate an idea to her without grammar. And it struck me that maybe this is what I was looking for. Instead of arranging words in an order, in sequence, as a sentence, you arrange them in this map, where they're all linked together not by placing them one after the other but in questions, in question-answer pairs. And so if you do this, then what you're conveying is not a sentence in English, but what you're conveying is really a meaning, the meaning of a sentence in English. Now, meaning is really the underbelly, in some sense, of language. It's what comes after thought but before language. And the idea was that this particular representation might convey meaning in its raw form. So I was very excited by this, you know, hopping around all over the place, trying to figure out if I can convert all possible sentences that I hear into this. And I found that this is not enough. Why is this not enough? This is not enough because if you wanted to convey something like negation, you want to say, "I don't want soup," then you can't do that by asking a question. You do that by changing the word "want." Again, if you wanted to say, "I wanted soup yesterday," you do that by converting the word "want" into "wanted." It's a past tense. So this is a flourish which I added to make the system complete. This is a map of words joined together as questions and answers, and with these filters

applied on top of them in order to modify them to represent certain nuances. Let me show you this with a different example. Let's take this sentence: "I told the carpenter I could not pay him." It's a fairly complicated sentence. The way that this particular system works, you can start with any part of this sentence. I'm going to start with the word "tell." So this is the word "tell." Now this happened in the past, so I'm going to make that "told." Now, what I'm going to do is, I'm going to ask questions. So, who told? I told. I told whom? I told the carpenter. Now we start with a different part of the sentence. We start with the word "pay," and we add the ability filter to it to make it "can pay." Then we make it "can't pay," and we can make it "couldn't pay" by making it the past tense. So who couldn't pay? I couldn't pay. Couldn't pay whom? I couldn't pay the carpenter. And then you join these two together by asking this question: What did I tell the carpenter? I told the carpenter I could not pay him. Now think about this. This is —(Applause)— this is a representation of this sentence without language. And there are two or three interesting things about this. First of all, I could have started anywhere. I didn't have to start with the word "tell." I could have started anywhere in the sentence, and I could have made this entire thing. The second thing is, if I wasn't an English speaker, if I was speaking in some other language, this map would actually hold true in any language. So long as the questions are standardized, the map is actually independent of language. So I call this FreeSpeech, and I was playing with this for many, many months. I was trying out so many different combinations of this. And then I noticed something very interesting about FreeSpeech. I was trying to convert language, convert sentences in English into sentences in FreeSpeech, and vice versa, and back and forth. And I realized that this particular configuration, this particular way of representing language, it allowed me to actually create very concise rules that go between FreeSpeech on one side and English on the other. So I could actually write this set of rules that translates from this particular representation into English. And so I developed this thing. I developed this thing called the FreeSpeech Engine which takes any FreeSpeech sentence as the input and gives out perfectly grammatical English text.

And by putting these two pieces together, the representation and the engine, I was able to create an app, a technology for children with autism, that not only gives them words but also gives them grammar. So I tried this out with kids with autism, and I found that there was an incredible amount of identification. They were able to create sentences in FreeSpeech which were much more complicated but much more effective than equivalent sentences in English, and I started thinking about why that might be the case. And I had an idea, and I want to talk to you about this idea next. In about 1997, about 15 years back, there were a group of scientists that were trying to understand how the brain processes language, and they found something very interesting. They found that when you learn a language as a child, as a two-year-old, you learn it with a certain part of your brain, and when you learn a language as an adult -- for example, if I wanted to learn Japanese right now — a completely different part of my brain is used. Now I don't know why that's the case, but my guess is that that's because when you learn a language as an adult, you almost invariably learn it through your native language, or through your first language. So what's interesting about FreeSpeech is that when you create a sentence or when you create language, a child with autism creates language with FreeSpeech, they're not using this support language, they're not using this bridge language. They're directly constructing the sentence. And so this gave me this idea. Is it possible to use FreeSpeech not for children with autism but to teach language to people without disabilities? And so I tried a number of experiments. The first thing I did was I built a jigsaw puzzle in which these questions and answers are coded in the form of shapes, in the form of colors, and you have people putting these together and trying to understand how this works. And I built an app out of it, a game out of it, in which children can play with words and with a reinforcement, a sound reinforcement of visual structures, they're able to learn language. And this, this has a lot of potential, a lot of promise, and the government of India recently licensed this technology from us, and they're going to try it out with millions of different children trying to teach them English. And the dream, the hope, the vision, really, is that when they learn English this way, they learn it with the same proficiency as their mother tongue.

All right, let's talk about something else. Let's talk about speech. This is speech. So speech is the primary mode of communication delivered between all of us. Now what's interesting about speech is that speech is one-dimensional. Why is it one-dimensional? It's one-dimensional because it's sound. It's also one-dimensional because our mouths are built that way. Our mouths are built to create one-dimensional sound. But if you think about the brain, the thoughts that we have in our heads are not one-dimensional. I mean, we have these rich, complicated, multi-dimensional ideas. Now, it seems to me that language is really the brain's invention to convert this rich, multi-dimensional thought on one hand into speech on the other hand. Now what's interesting is that we do a lot of work in information nowadays, and almost all of that is done in the language domain. Take Google, for example. Google trawls all these countless billions of websites, all of which are in English, and when you want to use Google, you go into Google search, and you type in English, and it matches the English with the English. What if we could do this in FreeSpeech instead? I have a suspicion that if we did this, we'd find that algorithms like searching, like retrieval, all of these things, are much simpler and also more effective, because they don't process the data structure of speech. Instead they're processing the data structure of thought. The data structure of thought. That's a provocative idea. But let's look at this in a little more detail. So this is the FreeSpeech ecosystem. We have the Free Speech representation on one side, and we have the FreeSpeech Engine, which generates English. Now if you think about it, FreeSpeech, I told you, is completely language-independent. It doesn't have any specific information in it which is about English. So everything that this system knows about English is actually encoded into the engine. That's a pretty interesting concept in itself. You've encoded an entire human language into a software program. But if you look at what's inside the engine, it's actually not very complicated. It's not very complicated code. And what's more interesting is the fact that the vast majority of the code in that engine is not really English-specific. And that gives this interesting idea. It might be very easy for us to actually create these engines in many, many different languages, in Hindi, in French, in German, in Swahili. And that gives another interesting idea.

For example, supposing I was a writer, say, for a newspaper or for a magazine. I could create content in one language, FreeSpeech, and the person who's consuming that content, the person who's reading that particular information could choose any engine, and they could read it in their own mother tongue, in their native language. I mean, this is an incredibly attractive idea, especially for India. We have so many different languages. There's a song about India, and there's a description of the country as, it says, (in Sanskrit). That means "ever-smiling speaker of beautiful languages." Language is beautiful. I think it's the most beautiful of human creations. I think it's the loveliest thing that our brains have invented. It entertains, it educates, it enlightens, but what I like the most about language is that it empowers. I want to leave you with this. This is a photograph of my collaborators, my earliest collaborators when I started working on language and autism and various other things. The girl's name is Pavna, and that's her mother, Kalpana. And Pavna's an entrepreneur, but her story is much more remarkable than mine, because Pavna is about 23. She has quadriplegic cerebral palsy, so ever since she was born, she could neither move nor talk. And everything that she's accomplished so far, finishing school, going to college, starting a company, collaborating with me to develop Avaz, all of these things she's done with nothing more than moving her eyes. Daniel Webster said this: He said, "If all of my possessions were taken from me with one exception, I would choose to keep the power of communication, for with it, I would regain all the rest." And that's why, of all of these incredible applications of FreeSpeech, the one that's closest to my heart still remains the ability for this to empower children with disabilities to be able to communicate, the power of communication, to get back all the rest. Thank you. (Applause) Thank you. (Applause) Thank you. Thank you. Thank you. (Applause) Thank you. Thank you. Thank you. (Applause)

Suicidal crickets, zombie roaches and other parasite tales By Ed Yong A herd of wildebeests, a shoal of fish, a flock of birds. Many animals gather in large groups that are among the most wonderful spectacles in the natural world. But why do these groups form? The common answers include things like seeking safety in numbers or hunting in packs or gathering to mate or breed, and all of these explanations, while often true, make a huge assumption about animal behavior, that the animals are in control of their own actions, that they are in charge of their bodies. And that is often not the case. This is Artemia, a brine shrimp. You probably know it better as a sea monkey. It's small, and it typically lives alone, but it can gather in these large red swarms that span for meters, and these form because of a parasite. These shrimp are infected with a tapeworm. A tapeworm is effectively a long, living gut with genitals at one end and a hooked mouth at the other. As a freelance journalist, I sympathize. (Laughter) The tapeworm drains nutrients from Artemia's body, but it also does other things. It castrates them, it changes their color from transparent to bright red, it makes them live longer, and as biologist Nicolas Rode has found, it makes them swim in groups. Why? Because the tapeworm, like many other parasites, has a complicated life cycle involving many different hosts. The shrimp are just one step on its journey. Its ultimate destination is this, the greater flamingo. Only in a flamingo can the tapeworm reproduce, so to get there, it manipulates its shrimp hosts into forming these conspicuous colored swarms that are easier for a flamingo to spot and to devour, and that is the secret of the Artemia swarm. They aren't sociable through their own volition, but because they are being controlled. It's not safety in numbers. It's actually the exact opposite. The tapeworm hijacks their brains and their bodies, turning them into vehicles for getting itself into a flamingo. And here is another example of a parasitic manipulation. This is a suicidal cricket. This cricket swallowed the larvae of a Gordian worm, or horsehair worm. The worm grew to adult size within it, but it needs to get into water in order to mate, and it does that by releasing proteins

that addle the cricket's brain, causing it to behave erratically. When the cricket nears a body of water, such as this swimming pool, it jumps in and drowns, and the worm wriggles out of its suicidal corpse. Crickets are really roomy. Who knew? The tapeworm and the Gordian worm are not alone. They are part of an entire cavalcade of mind-controlling parasites, of fungi, viruses, and worms and insects and more that all specialize in subverting and overriding the wills of their hosts. Now, I first learned about this way of life through David Attenborough's "Trials of Life" about 20 years ago, and then later through a wonderful book called "Parasite Rex" by my friend Carl Zimmer. And I've been writing about these creatures ever since. Few topics in biology enthrall me more. It's like the parasites have subverted my own brain. Because after all, they are always compelling and they are delightfully macabre. When you write about parasites, your lexicon swells with phrases like "devoured alive" and "bursts out of its body." (Laughter) But there's more to it than that. I'm a writer, and fellow writers in the audience will know that we love stories. Parasites invite us to resist the allure of obvious stories. Their world is one of plot twists and unexpected explanations. Why, for example, does this caterpillar start violently thrashing about when another insect gets close to it and those white cocoons that it seems to be standing guard over? Is it maybe protecting its siblings? No. This caterpillar was attacked by a parasitic wasp which laid eggs inside it. The eggs hatched and the young wasps devoured the caterpillar alive before bursting out of its body. See what I mean? Now, the caterpillar didn't die. Some of the wasps seemed to stay behind and controlled it into defending their siblings which are metamorphosing into adults within those cocoons. This caterpillar is a head-banging zombie bodyguard defending the offspring of the creature that killed it. (Applause) We have a lot to get through. I only have 13 minutes. (Laughter)

Now, some of you are probably just desperately clawing for some solace in the idea that these things are oddities of the natural world, that they are outliers, and that point of view is understandable, because by their nature, parasites are quite small and they spend a lot of their time inside the bodies of other things. They're easy to overlook, but that doesn't mean that they aren't important. A few years back, a man called Kevin Lafferty took a group of scientists into three Californian estuaries and they pretty much weighed and dissected and recorded everything they could find, and what they found were parasites in extreme abundance. Especially common were trematodes, tiny worms that specialize in castrating their hosts like this unfortunate snail. Now, a single trematode is tiny, microscopic, but collectively they weighed as much as all the fish in the estuaries and three to nine times more than all the birds. And remember the Gordian worm that I showed you, the cricket thing? One Japanese scientist called Takuya Sato found that in one stream, these things drive so many crickets and grasshoppers into the water that the drowned insects make up some 60 percent of the diet of local trout. Manipulation is not an oddity. It is a critical and common part of the world around us, and scientists have now found hundreds of examples of such manipulators, and more excitingly, they're starting to understand exactly how these creatures control their hosts. And this is one of my favorite examples. This is Ampulex compressa, the emerald cockroach wasp, and it is a truth universally acknowledged that an emerald cockroach wasp in possession of some fertilized eggs must be in want of a cockroach. When she finds one, she stabs it with a stinger that is also a sense organ. This discovery came out three weeks ago. She stabs it with a stinger that is a sense organ equipped with small sensory bumps that allow her to feel the distinctive texture of a roach's brain. So like a person blindly rooting about in a bag, she finds the brain, and she injects it with venom into two very specific clusters of neurons. Israeli scientists Frederic Libersat and Ram Gal found that the venom is a very specific chemical weapon. It doesn't kill the roach, nor does it sedate it. The roach could walk away or fly or run if it chose to, but it doesn't choose to, because the venom nixes its motivation to walk, and only that. The wasp basically un-checks the escape-from-danger box in the roach's operating system, allowing her to lead her helpless victim back to her lair by its antennae like a person walking a dog. And once

there, she lays an egg on it, egg hatches, devoured alive, bursts out of body, yadda yadda yadda, you know the drill. (Laughter) (Applause) Now I would argue that, once stung, the cockroach isn't a roach anymore. It's more of an extension of the wasp, just like the cricket was an extension of the Gordian worm. These hosts won't get to survive or reproduce. They have as much control over their own fates as my car. Once the parasites get in, the hosts don't get a say. Now humans, of course, are no stranger to manipulation. We take drugs to shift the chemistries of our brains and to change our moods, and what are arguments or advertising or big ideas if not an attempt to influence someone else's mind? But our attempts at doing this are crude and blundering compared to the fine-grained specificity of the parasites. Don Draper only wishes he was as elegant and precise as the emerald cockroach wasp. Now, I think this is part of what makes parasites so sinister and so compelling. We place such a premium on our free will and our independence that the prospect of losing those qualities to forces unseen informs many of our deepest societal fears. Orwellian dystopias and shadowy cabals and mind-controlling supervillains -these are tropes that fill our darkest fiction, but in nature, they happen all the time. Which leads me to an obvious and disquieting question: Are there dark, sinister parasites that are influencing our behavior without us knowing about it, besides the NSA? If there are any — (Laughter) (Applause) I've got a red dot on my forehead now, don't I? (Laughter) If there are any, this is a good candidate for them. This is Toxoplasma gondii, or Toxo, for short, because the terrifying creature always deserves a cute nickname. Toxo infects mammals, a wide variety of mammals, but it can only sexually reproduce in a cat. And scientists like Joanne Webster have shown that if Toxo gets into a rat or a mouse, it turns the rodent into a cat-seeking missile. If the infected rat smells the delightful odor of cat piss, it runs towards the source of the smell rather than the more sensible direction of away. The cat eats the rat. Toxo gets to have sex. It's a classic tale of Eat, Prey, Love. (Laughter) (Applause)

You're very charitable, generous people. Hi, Elizabeth, I loved your talk. How does the parasite control its host in this way? We don't really know. We know that Toxo releases an enzyme that makes dopamine, a substance involved in reward and motivation. We know it targets certain parts of a rodent's brain, including those involved in sexual arousal. But how those puzzle pieces fit together is not immediately clear. What is clear is that this thing is a single cell. This has no nervous system. It has no consciousness. It doesn't even have a body. But it's manipulating a mammal? We are mammals. We are more intelligent than a mere rat, to be sure, but our brains have the same basic structure, the same types of cells, the same chemicals running through them, and the same parasites. Estimates vary a lot, but some figures suggest that one in three people around the world have Toxo in their brains. Now typically, this doesn't lead to any overt illness. The parasite holds up in a dormant state for a long period of time. But there's some evidence that those people who are carriers score slightly differently on personality questionnaires than other people, that they have a slightly higher risk of car accidents, and there's some evidence that people with schizophrenia are more likely to be infected. Now, I think this evidence is still inconclusive, and even among Toxo researchers, opinion is divided as to whether the parasite is truly influencing our behavior. But given the widespread nature of such manipulations, it would be completely implausible for humans to be the only species that weren't similarly affected. And I think that this capacity to constantly subvert our way of thinking about the world makes parasites amazing. They're constantly inviting us to look at the natural world sideways, and to ask if the behaviors we're seeing, whether they're simple and obvious or baffling and puzzling, are not the results of individuals acting through their own accord but because they are being bent to the control of something else. And while that idea may be disquieting, and while parasites' habits may be very grisly, I think that ability to surprise us makes them as wonderful and as charismatic as any panda or butterfly or dolphin. At the end of "On the Origin of Species," Charles Darwin writes about the grandeur of life, and of endless forms most beautiful and most wonderful, and I like to think he could easily have been talking about a

tapeworm that makes shrimp sociable or a wasp that takes cockroaches for walks. But perhaps, that's just a parasite talking. Thank you. (Applause) Teach teachers how to create magic By Cristopher Emdin Right now there is an aspiring teacher who is working on a 60-page paper based on some age-old education theory developed by some dead education professor wondering to herself what this task that she's engaging in has to do with what she wants to do with her life, which is be an educator, change lives, and spark magic. Right now there is an aspiring teacher in a graduate school of education who is watching a professor babble on and on about engagement in the most disengaging way possible. Right now there's a first-year teacher at home who is pouring through lesson plans trying to make sense of standards, who is trying to make sense of how to grade students appropriately, while at the same time saying to herself over and over again, "Don't smile till November," because that's what she was taught in her teacher education program. Right now there's a student who is coming up with a way to convince his mom or dad that he's very, very sick and can't make it to school tomorrow. On the other hand, right now there are amazing educators that are sharing information, information that is shared in such a beautiful way that the students are sitting at the edge of their seats just waiting for a bead of sweat to drop off the face of this person so they can soak up all that knowledge. Right now there is also a person who has an entire audience rapt with attention, a person that is weaving a powerful narrative about a world that the people who are listening have never imagined or seen before, but if they close their eyes tightly enough, they can envision that world because the storytelling is so compelling. Right now there's a person who can tell an audience to put

their hands up in the air and they will stay there till he says, "Put them down." Right now. So people will then say, "Well, Chris, you describe the guy who is going through some awful training but you're also describing these powerful educators. If you're thinking about the world of education or urban education in particular, these guys will probably cancel each other out, and then we'll be okay." The reality is, the folks I described as the master teachers, the master narrative builders, the master storytellers are far removed from classrooms. The folks who know the skills about how to teach and engage an audience don't even know what teacher certification means. They may not even have the degrees to be able to have anything to call an education. And that to me is sad. It's sad because the people who I described, they were very disinterested in the learning process, want to be effective teachers, but they have no models. I'm going to paraphrase Mark Twain. Mark Twain says that proper preparation, or teaching, is so powerful that it can turn bad morals to good, it can turn awful practices into powerful ones, it can change men and transform them into angels. The folks who I described earlier got proper preparation in teaching, not in any college or university, but by virtue of just being in the same spaces of those who engage. Guess where those places are? Barber shops, rap concerts, and most importantly, in the black church. And I've been framing this idea called Pentecostal pedagogy. Who here has been to a black church? We got a couple of hands. You go to a black church, their preacher starts off and he realizes that he has to engage the audience, so he starts off with this sort of wordplay in the beginning oftentimes, and then he takes a pause, and he says, "Oh my gosh, they're not quite paying attention." So he says, "Can I get an amen?" Audience: Amen. Chris Emdin: So I can I get an amen? Audience: Amen. CE: And all of a sudden, everybody's reawoken. That preacher bangs on the pulpit for attention. He drops his voice at a very, very low volume

when he wants people to key into him, and those things are the skills that we need for the most engaging teachers. So why does teacher education only give you theory and theory and tell you about standards and tell you about all of these things that have nothing to do with the basic skills, that magic that you need to engage an audience, to engage a student? So I make the argument that we reframe teacher education, that we could focus on content, and that's fine, and we could focus on theories, and that's fine, but content and theories with the absence of the magic of teaching and learning means nothing. Now people oftentimes say, "Well, magic is just magic." There are teachers who, despite all their challenges, who have those skills, get into those schools and are able to engage an audience, and the administrator walks by and says, "Wow, he's so good, I wish all my teachers could be that good." And when they try to describe what that is, they just say, "He has that magic." But I'm here to tell you that magic can be taught. Magic can be taught. Magic can be taught. Now, how do you teach it? You teach it by allowing people to go into those spaces where the magic is happening. If you want to be an aspiring teacher in urban education, you've got to leave the confines of that university and go into the hood. You've got to go in there and hang out at the barbershop, you've got to attend that black church, and you've got to view those folks that have the power to engage and just take notes on what they do. At our teacher education classes at my university, I've started a project where every single student that comes in there sits and watches rap concerts. They watch the way that the rappers move and talk with their hands. They study the way that he walks proudly across that stage. They listen to his metaphors and analogies, and they start learning these little things that if they practice enough becomes the key to magic. They learn that if you just stare at a student and raise your eyebrow about a quarter of an inch, you don't have to say a word because they know that that means that you want more. And if we could transform teacher education to focus on teaching teachers how to create that magic then poof! we could make dead classes come alive, we could reignite imaginations, and we can change education.

Thank you. (Applause) My daughter Malala By Ziauddin Yousafzai In many patriarchal societies and tribal societies, fathers are usually known by their sons, but I'm one of the few fathers who is known by his daughter, and I am proud of it. (Applause) Malala started her campaign for education and stood for her rights in 2007, and when her efforts were honored in 2011, and she was given the national youth peace prize, and she became a very famous, very popular young girl of her country. Before that, she was my daughter, but now I am her father. Ladies and gentlemen, if we glance to human history, the story of women is the story of injustice, inequality, violence and exploitation. You see, in patriarchal societies, right from the very beginning, when a girl is born, her birth is not celebrated. She is not welcomed, neither by father nor by mother. The neighborhood comes and commiserates with the mother, and nobody congratulates the father. And a mother is very uncomfortable for having a girl child. When she gives birth to the first girl child, first daughter, she is sad. When she gives birth to the second daughter, she is shocked, and in the expectation of a son, when she gives birth to a third daughter, she feels guilty like a criminal. Not only the mother suffers, but the daughter, the newly born daughter, when she grows old, she suffers too. At the age of five, while she should be going to school, she stays at home and her brothers are admitted in a school. Until the age of 12, somehow, she has a good life. She can have fun. She can play with her friends in the streets, and she can move around in the streets like a butterfly. But when she enters her teens, when she becomes 13 years old, she is forbidden to go out of her home without a male escort. She is confined under the four walls of her home.

She is no more a free individual. She becomes the so-called honor of her father and of her brothers and of her family, and if she transgresses the code of that so-called honor, she could even be killed. And it is also interesting that this so-called code of honor, it does not only affect the life of a girl, it also affects the life of the male members of the family. I know a family of seven sisters and one brother, and that one brother, he has migrated to the Gulf countries, to earn a living for his seven sisters and parents, because he thinks that it will be humiliating if his seven sisters learn a skill and they go out of the home and earn some livelihood. So this brother, he sacrifices the joys of his life and the happiness of his sisters at the altar of so-called honor. And there is one more norm of the patriarchal societies that is called obedience. A good girl is supposed to be very quiet, very humble and very submissive. It is the criteria. The role model good girl should be very quiet. She is supposed to be silent and she is supposed to accept the decisions of her father and mother and the decisions of elders, even if she does not like them. If she is married to a man she doesn't like or if she is married to an old man, she has to accept, because she does not want to be dubbed as disobedient. If she is married very early, she has to accept. Otherwise, she will be called disobedient. And what happens at the end? In the words of a poetess, she is wedded, bedded, and then she gives birth to more sons and daughters. And it is the irony of the situation that this mother, she teaches the same lesson of obedience to her daughter and the same lesson of honor to her sons. And this vicious cycle goes on, goes on. Ladies and gentlemen, this plight of millions of women could be changed if we think differently, if women and men think differently, if men and women in the tribal and patriarchal societies in the developing countries, if they can break a few norms of family and society, if they can abolish the discriminatory laws of the systems in their states, which go against the basic human rights of the women. Dear brothers and sisters, when Malala was born, and for the first time, believe me, I don't like newborn children, to be honest, but when I went and I looked into her eyes, believe me, I got extremely honored. And

long before she was born, I thought about her name, and I was fascinated with a heroic legendary freedom fighter in Afghanistan. Her name was Malalai of Maiwand, and I named my daughter after her. A few days after Malala was born, my daughter was born, my cousin came -- and it was a coincidence -- he came to my home and he brought a family tree, a family tree of the Yousafzai family, and when I looked at the family tree, it traced back to 300 years of our ancestors. But when I looked, all were men, and I picked my pen, drew a line from my name, and wrote, "Malala." And when she grow old, when she was four and a half years old, I admitted her in my school. You will be asking, then, why should I mention about the admission of a girl in a school? Yes, I must mention it. It may be taken for granted in Canada, in America, in many developed countries, but in poor countries, in patriarchal societies, in tribal societies, it's a big event for the life of girl. Enrollment in a school means recognition of her identity and her name. Admission in a school means that she has entered the world of dreams and aspirations where she can explore her potentials for her future life. I have five sisters, and none of them could go to school, and you will be astonished, two weeks before, when I was filling out the Canadian visa form, and I was filling out the family part of the form, I could not recall the surnames of some of my sisters. And the reason was that I have never, never seen the names of my sisters written on any document. That was the reason that I valued my daughter. What my father could not give to my sisters and to his daughters, I thought I must change it. I used to appreciate the intelligence and the brilliance of my daughter. I encouraged her to sit with me when my friends used to come. I encouraged her to go with me to different meetings. And all these good values, I tried to inculcate in her personality. And this was not only she, only Malala. I imparted all these good values to my school, girl students and boy students as well. I used education for emancipation. I taught my girls, I taught my girl students, to unlearn the lesson of obedience. I taught my boy students to unlearn the lesson of so-called pseudo-honor. Dear brothers and sisters, we were striving for more rights for women, and we were struggling to have more, more and more space for the

women in society. But we came across a new phenomenon. It was lethal to human rights and particularly to women's rights. It was called Talibanization. It means a complete negation of women's participation in all political, economical and social activities. Hundreds of schools were lost. Girls were prohibited from going to school. Women were forced to wear veils and they were stopped from going to the markets. Musicians were silenced, girls were flogged and singers were killed. Millions were suffering, but few spoke, and it was the most scary thing when you have all around such people who kill and who flog, and you speak for your rights. It's really the most scary thing. At the age of 10, Malala stood, and she stood for the right of education. She wrote a diary for the BBC blog, she volunteered herself for the New York Times documentaries, and she spoke from every platform she could. And her voice was the most powerful voice. It spread like a crescendo all around the world. And that was the reason the Taliban could not tolerate her campaign, and on October 9 2012, she was shot in the head at point blank range. It was a doomsday for my family and for me. The world turned into a big black hole. While my daughter was on the verge of life and death, I whispered into the ears of my wife, "Should I be blamed for what happened to my daughter and your daughter?" And she abruptly told me, "Please don't blame yourself. You stood for the right cause. You put your life at stake for the cause of truth, for the cause of peace, and for the cause of education, and your daughter in inspired from you and she joined you. You both were on the right path and God will protect her." These few words meant a lot to me, and I didn't ask this question again. When Malala was in the hospital, and she was going through the severe pains and she had had severe headaches because her facial nerve was cut down, I used to see a dark shadow spreading on the face of my wife. But my daughter never complained. She used to tell us, "I'm fine with my crooked smile and with my numbness in my face. I'll be okay. Please don't worry." She was a solace for us, and she consoled us.

Dear brothers and sisters, we learned from her how to be resilient in the most difficult times, and I'm glad to share with you that despite being an icon for the rights of children and women, she is like any 16-year old girl. She cries when her homework is incomplete. She quarrels with her brothers, and I am very happy for that. People ask me, what special is in my mentorship which has made Malala so bold and so courageous and so vocal and poised? I tell them, don't ask me what I did. Ask me what I did not do. I did not clip her wings, and that's all. Thank you very much. (Applause) Thank you. Thank you very much. Thank you. (Applause) A 50-cent microscope that folds like origami. By Manu Prakash The year is 1800. A curious little invention is being talked about. It's called a microscope. What it allows you to do is see tiny little lifeforms that are invisible to the naked eye. Soon comes the medical discovery that many of these lifeforms are actually causes of terrible human diseases. Imagine what happened to the society when they realized that an English mom in her teacup actually was drinking a monster soup, not very far from here. This is from London. Fast forward 200 years. We still have this monster soup around, and it's taken hold in the developing countries around the tropical belt. Just for malaria itself, there are a million deaths a year, and more than a billion people that need to be tested because they are at risk for different species of malarial infections. Now it's actually very simple to put a face to many of these monsters. You take a stain, like acridine orange or a fluorescent stain or Giemsa, and a microscope, and you look at them. They all have faces. Why is that so, that Alex in Kenya, Fatima in Bangladesh, Navjoot in Mumbai, and

Julie and Mary in Uganda still wait months to be able to diagnose why they are sick? And that's primarily because scalability of the diagnostics is completely out of reach. And remember that number: one billion. The problem lies with the microscope itself. Even though the pinnacle of modern science, research microscopes are not designed for field testing. Neither were they first designed for diagnostics at all. They are heavy, bulky, really hard to maintain, and cost a lot of money. This picture is Mahatma Gandhi in the '40s using the exact same setup that we actually use today for diagnosing T.B. in his ashram in Sevagram in India. Two of my students, Jim and James, traveled around India and Thailand, starting to think about this problem a lot. We saw all kinds of donated equipment. We saw fungus growing on microscope lenses. And we saw people who had a functional microscope but just didn't know how to even turn it on. What grew out of that work and that trip was actually the idea of what we call Foldscopes. So what is a Foldscope? A Foldscope is a completely functional microscope, a platform for fluorescence, bright-field, polarization, projection, all kinds of advanced microscopy built purely by folding paper. So, now you think, how is that possible? I'm going to show you some examples here, and we will run through some of them. It starts with a single sheet of paper. What you see here is all the possible components to build a functional bright-field and fluorescence microscope. So, there are three stages: There is the optical stage, the illumination stage and the mask-holding stage. And there are micro optics at the bottom that's actually embedded in the paper itself. What you do is, you take it on, and just like you are playing like a toy, which it is, I tab it off, and I break it off. This paper has no instructions and no languages. There is a code, a color code embedded, that tells you exactly how to fold that specific microscope. When it's done, it looks something like this, has all the functionalities of a standard microscope, just like an XY stage, a place where a sample slide could go, for example right here. We didn't want to change this, because this is the standard that's been optimized for over the years, and many health workers are actually used to this. So this is

what changes, but the standard stains all remain the same for many different diseases. You pop this in. There is an XY stage, and then there is a focusing stage, which is a flexure mechanism that's built in paper itself that allows us to move and focus the lenses by micron steps. So what's really interesting about this object, and my students hate when I do this, but I'm going to do this anyway, is these are rugged devices. I can turn it on and throw it on the floor and really try to stomp on it. And they last, even though they're designed from a very flexible material, like paper. Another fun fact is, this is what we actually send out there as a standard diagnostic tool, but here in this envelope I have 30 different foldscopes of different configurations all in a single folder. And I'm going to pick one randomly. This one, it turns out, is actually designed specifically for malaria, because it has the fluorescent filters built specifically for diagnosing malaria. So the idea of very specific diagnostic microscopes comes out of this. So up till now, you didn't actually see what I would see from one of these setups. So what I would like to do is, if we could dim the lights, please, it turns out foldscopes are also projection microscopes. I have these two microscopes that I'm going to turn -- go to the back of the wall -- and just project, and this way you will see exactly what I would see. What you're looking at -- (Applause) — This is a cross-section of a compound eye, and when I'm going to zoom in closer, right there, I am going through the z-axis. You actually see how the lenses are cut together in the cross-section pattern. Another example, one of my favorite insects, I love to hate this one, is a mosquito, and you're seeing the antenna of a culex pipiens. Right there. All from the simple setup that I actually described. So my wife has been field testing some of our microscopes by washing my clothes whenever I forget them in the dryer. So it turns out they're waterproof, and -- (Laughter) — right here is just fluorescent water, and I don't know if you can actually see this. This also shows you how the projection scope works. You get to see the beam the way it's projected and bent.

Can we get the lights back on again? So I'm quickly going to show you, since I'm running out of time, in terms of how much it costs for us to manufacture, the biggest idea was roll-toroll manufacturing, so we built this out of 50 cents of parts and costs. (Applause) And what this allows us to do is to think about a new paradigm in microscopy, which we call use-and-throw microscopy. I'm going to give you a quick snapshot of some of the parts that go in. Here is a sheet of paper. This is when we were thinking about the idea. This is an A4 sheet of paper. These are the three stages that you actually see. And the optical components, if you look at the inset up on the right, we had to figure out a way to manufacture lenses in paper itself at really high throughputs, so it uses a process of self-assembly and surface tension to build achromatic lenses in the paper itself. So that's where the lenses go. There are some light sources. And essentially, in the end, all the parts line up because of origami, because of the fact that origami allows us micron-scale precision of optical alignment. So even though this looks like a simple toy, the aspects of engineering that go in something like this are fairly sophisticated. So here is another obvious thing that we would do, typically, if I was going to show that these microscopes are robust, is go to the third floor and drop it from the floor itself. There it is, and it survives. So for us, the next step actually is really finishing our field trials. We are starting at the end of the summer. We are at a stage where we'll be making thousands of microscopes. That would be the first time where we would be doing field trials with the highest density of microscopes ever at a given place. We've started collecting data for malaria, Chagas disease and giardia from patients themselves. And I want to leave you with this picture. I had not anticipated this before, but a really interesting link between hands-on science education and global health. What are the tools that we're actually providing the kids who are going to fight this monster soup for tomorrow? I would love for them to be able to just print out a Foldscope and carry them around in their pockets.

Thank you. (Applause)

‫חוו''ר אז'' מ''יק‬ Xavier Ozdiken Moyek