When we talk about English, we often think of it as a single language but what do the dialects spoken in dozens of countries around the world have in common with each other, or with the writings of Chaucer?
And how are any of them related to the strange words in Beowulf?
The answer is that like most languages, English has evolved through generations of speakers, undergoing major changes over time.
By undoing these changes, we can trace the language from the present day back to its ancient roots.
While modern English shares many similar words with Latin-derived romance languages, like French and Spanish, most of those words were not originally part of it.
Instead, they started coming into the language with the Norman invasion of England in 1066.
When the French-speaking Normans conquered England and became its ruling class, they brought their speech with them, adding a massive amount of French and Latin vocabulary to the English language previously spoken there.
Today, we call that language Old English.
This is the language of Beowulf.
It probably doesn't look very familiar, but it might be more recognizable if you know some German.
That's because Old English belongs to the Germanic language family, first brought to the British Isles in the 5th and 6th centuries by the Angles, Saxons, and Jutes.
The Germanic dialects they spoke would become known as Anglo-Saxon.
Viking invaders in the 8th to 11th centuries added more borrowings from Old Norse into the mix.
It may be hard to see the roots of modern English underneath all the words borrowed from French, Latin, Old Norse and other languages.
But comparative linguistics can help us by focusing on grammatical structure, patterns of sound changes, and certain core vocabulary.
For example, after the 6th century, German words starting with "p," systematically shifted to a "pf" sound while their Old English counterparts kept the "p" unchanged.
In another split, words that have "sk" sounds in Swedish developed an "sh" sound in English.
There are still some English words with "sk," like "skirt," and "skull," but they're direct borrowings from Old Norse that came after the "sk" to "sh" shift.
These examples show us that just as the various Romance languages descended from Latin, English, Swedish, German, and many other languages descended from their own common ancestor known as Proto-Germanic spoken around 500 B.C.E.
Because this historical language was never written down, we can only reconstruct it by comparing its descendants, which is possible thanks to the consistency of the changes.
We can even use the same process to go back one step further, and trace the origins of Proto-Germanic to a language called Proto-Indo-European, spoken about 6000 years ago on the Pontic steppe in modern day Ukraine and Russia.
This is the reconstructed ancestor of the Indo-European family that includes nearly all languages historically spoken in Europe, as well as large parts of Southern and Western Asia.
And though it requires a bit more work, we can find the same systematic similarities, or correspondences, between related words in different Indo-European branches.
Comparing English with Latin, we see that English has "t" where Latin has "d", and "f" where latin has "p" at the start of words.
Some of English's more distant relatives include Hindi, Persian and the Celtic languages it displaced in what is now Britain.
Proto-Indo-European itself descended from an even more ancient language, but unfortunately, this is as far back as historical and archeological evidence will allow us to go.
Many mysteries remain just out of reach, such as whether there might be a link between Indo-European and other major language families, and the nature of the languages spoken in Europe prior to its arrival.
But the amazing fact remains that nearly 3 billion people around the world, many of whom cannot understand each other, are nevertheless speaking the same words shaped by 6000 years of history.
This is a map of New York State that was made in 1937 by the General Drafting Company.
It's an extremely famous map among cartography nerds, because down here at the bottom of the Catskill Mountains, there is a little town called Roscoe -- actually, this will go easier if I just put it up here -- There's Roscoe, and then right above Roscoe is Rockland, New York, and then right above that is the tiny town of Agloe, New York.
Agloe, New York, is very famous to cartographers, because it's a paper town.
It's also known as a copyright trap.
Mapmakers -- because my map of New York and your map of New York are going to look very similar, on account of the shape of New York -- often, mapmakers will insert fake places onto their maps, in order to protect their copyright.
Because then, if my fake place shows up on your map, I can be well and truly sure that you have robbed me.
Agloe is a scrabblization of the initials of the two guys who made this map, Ernest Alpers and Otto [G.]
Lindberg, and they released this map in 1937.
Decades later, Rand McNally releases a map with Agloe, New York, on it, at the same exact intersection of two dirt roads in the middle of nowhere.
Well, you can imagine the delight over at General Drafting.
They immediately call Rand McNally, and they say, "We've caught you!
We made Agloe, New York, up.
It is a fake place.
It's a paper town.
We're going to sue your pants off!"
And Rand McNally says, "No, no, no, no, Agloe is real."
Because people kept going to that intersection of two dirt roads -- (Laughter) in the middle of nowhere, expecting there to be a place called Agloe -- someone built a place called Agloe, New York.
(Laughter) It had a gas station, a general store, two houses at its peak.
(Laughter) And this is of course a completely irresistible metaphor to a novelist, because we would all like to believe that the stuff that we write down on paper can change the actual world in which we're actually living, which is why my third book is called "Paper Towns".
But what interests me ultimately more than the medium in which this happened, is the phenomenon itself.
It's easy enough to say that the world shapes our maps of the world, right?
Like the overall shape of the world is obviously going to affect our maps.
But what I find a lot more interesting is the way that the manner in which we map the world changes the world.
Because the world would truly be a different place if North were down.
And the world would be a truly different place if Alaska and Russia weren't on opposite sides of the map.
And the world would be a different place if we projected Europe to show it in its actual size.
The world is changed by our maps of the world.
The way that we choose -- sort of, our personal cartographic enterprise, also shapes the map of our lives, and that in turn shapes our lives.
I believe that what we map changes the life we lead.
And I don't mean that in some, like, secret-y Oprah's Angels network, like, you-can-think-your-way- out-of-cancer sense.
But I do believe that while maps don't show you where you will go in your life, they show you where you might go.
You very rarely go to a place that isn't on your personal map.
So I was a really terrible student when I was a kid.
My GPA was consistently in the low 2s.
And I think the reason that I was such a terrible student is that I felt like education was just a series of hurdles that had been erected before me, and I had to jump over in order to achieve adulthood.
And I didn't really want to jump over these hurdles, because they seemed completely arbitrary, so I often wouldn't, and then people would threaten me, you know, they'd threaten me with this "going on [my] permanent record," or "You'll never get a good job."
I didn't want a good job!
As far as I could tell at eleven or twelve years old, like, people with good jobs woke up very early in the morning, (Laughter) and the men who had good jobs, one of the first things they did was tie a strangulation item of clothing around their necks.
They literally put nooses on themselves, and then they went off to their jobs, whatever they were.
That's not a recipe for a happy life.
These people -- in my, symbol-obsessed, twelve year-old imagination -- these people who are strangling themselves as one of the first things they do each morning, they can't possibly be happy.
Why would I want to jump over all of these hurdles and have that be the end?
That's a terrible end!
And then, when I was in tenth grade, I went to this school, Indian Springs School, a small boarding school, outside of Birmingham, Alabama.
And all at once I became a learner.
And I became a learner, because I found myself in a community of learners.
I found myself surrounded by people who celebrated intellectualism and engagement, and who thought that my ironic oh-so-cool disengagement wasn't clever, or funny, but, like, it was a simple and unspectacular response to very complicated and compelling problems.
And so I started to learn, because learning was cool.
I learned that some infinite sets are bigger than other infinite sets, and I learned that iambic pentameter is and why it sounds so good to human ears.
I learned that the Civil War was a nationalizing conflict, I learned some physics, I learned that correlation shouldn't be confused with causation -- all of these things, by the way, enriched my life on a literally daily basis.
And it's true that I don't use most of them for my "job," but that's not what it's about for me.
It's about cartography.
What is the process of cartography?
It's, you know, sailing upon some land, and thinking, "I think I'll draw that bit of land," and then wondering, "Maybe there's some more land to draw."
And that's when learning really began for me.
It's true that I had teachers that didn't give up on me, and I was very fortunate to have those teachers, because I often gave them cause to think there was no reason to invest in me.
But a lot of the learning that I did in high school wasn't about what happened inside the classroom, it was about what happened outside of the classroom.
For instance, I can tell you that "There's a certain Slant of light, Winter Afternoons -- That oppresses, like the Heft Of Cathedral Tunes --" not because I memorized Emily Dickinson in school when I was in high school, but because there was a girl when I was in high school, and her name was Amanda, and I had a crush on her, and she liked Emily Dickinson poetry.
The reason I can tell you what opportunity cost is, is because one day when I was playing Super Mario Kart on my couch, my friend Emmet walked in, and he said, "How long have you been playing Super Mario Kart?"
And I said, "I don't know, like, six hours?" and he said, "Do you realize that if you'd worked at Baskin-Robbins those six hours, you could have made 30 dollars, so in some ways, you just paid thirty dollars to play Super Mario Kart."
And I was, like, "I'll take that deal."
(Laughter) But I learned what opportunity cost is.
And along the way, the map of my life got better.
It got bigger; it contained more places.
There were more things that might happen, more futures I might have.
It wasn't a formal, organized learning process, and I'm happy to admit that.
It was spotty, it was inconsistent, there was a lot I didn't know.
I might know, you know, Cantor's idea that some infinite sets are larger than other infinite sets, but I didn't really understand the calculus behind that idea.
I might know the idea of opportunity cost, but I didn't know the law of diminishing returns.
But the great thing about imagining learning as cartography, instead of imagining it as arbitrary hurdles that you have to jump over, is that you see a bit of coastline, and that makes you want to see more.
And so now I do know at least some of the calculus that underlies all of that stuff.
So, I had one learning community in high school, then I went to another for college, and then I went to another, when I started working at a magazine called "Booklist," where I was an assistant, surrounded by astonishingly well-read people.
And then I wrote a book.
And like all authors dream of doing, I promptly quit my job.
(Laughter) And for the first time since high school, I found myself without a learning community, and it was miserable.
I hated it.
I read many, many books during this two-year period.
I read books about Stalin, and books about how the Uzbek people came to identify as Muslims, and I read books about how to make atomic bombs, but it just felt like I was creating my own hurdles, and then jumping over them myself, instead of feeling the excitement of being part of a community of learners, a community of people who are engaged together in the cartographic enterprise of trying to better understand and map the world around us.
And then, in 2006, I met that guy.
His name is Ze Frank.
I didn't actually meet him, just on the Internet.
Ze Frank was running, at the time, a show called "The Show with Ze Frank," and I discovered the show, and that was my way back into being a community learner again.
Here's Ze talking about Las Vegas: (Video) Ze Frank: Las Vegas was built in the middle of a huge, hot desert.
Almost everything here was brought from somewhere else -- the sort of rocks, the trees, the waterfalls.
These fish are almost as out of place as my pig that flew.
Contrasted to the scorching desert that surrounds this place, so are these people.
Things from all over the world have been rebuilt here, away from their histories, and away from the people that experience them differently.
Sometimes improvements were made -- even the Sphinx got a nose job.
Here, there's no reason to feel like you're missing anything.
This New York means the same to me as it does to everyone else.
Everything is out of context, and that means context allows for everything: Self Parking, Events Center, Shark Reef.
This fabrication of place could be one of the world's greatest achievements, because no one belongs here; everyone does.
As I walked around this morning, I noticed most of the buildings were huge mirrors reflecting the sun back into the desert.
But unlike most mirrors, which present you with an outside view of yourself embedded in a place, these mirrors come back empty.
John Green: Makes me nostalgic for the days when you could see the pixels in online video.
(Laughter) Ze isn't just a great public intellectual, he's also a brilliant community builder, and the community of people that built up around these videos was in many ways a community of learners.
So we played Ze Frank at chess collaboratively, and we beat him.
We organized ourselves to take a young man on a road trip across the United States.
We turned the Earth into a sandwich, by having one person hold a piece of bread at one point on the Earth, and on the exact opposite point of the Earth, have another person holding a piece of bread.
I realize that these are silly ideas, but they are also "learny" ideas, and that was what was so exciting to me, and if you go online, you can find communities like this all over the place.
Follow the calculus tag on Tumblr, and yes, you will see people complaining about calculus, but you'll also see people re-blogging those complaints, making the argument that calculus is interesting and beautiful, and here's a way in to thinking about the problem that you find unsolvable.
You can go to places like Reddit, and find sub-Reddits, like "Ask a Historian" or "Ask Science," where you can ask people who are in these fields a wide range of questions, from very serious ones to very silly ones.
But to me, the most interesting communities of learners that are growing up on the Internet right now are on YouTube, and admittedly, I am biased.
But I think in a lot of ways, the YouTube page resembles a classroom.
Look for instance at "Minute Physics," a guy who's teaching the world about physics: (Video) Let's cut to the chase.
As of July 4, 2012, the Higgs boson is the last fundamental piece of the standard model of particle physics to be discovered experimentally.
But, you might ask, why was the Higgs boson included in the standard model, alongside well-known particles like electrons and photons and quarks, if it hadn't been discovered back then in the 1970s?
Good question.
There are two main reasons.
First, just like the electron is an excitation in the electron field, the Higgs boson is simply a particle which is an excitation of the everywhere-permeating Higgs field.
The Higgs field in turn plays an integral role in our model for the weak nuclear force.
In particular, the Higgs field helps explain why it's so weak.
We'll talk more about this in a later video, but even though weak nuclear theory was confirmed in the 1980s, in the equations, the Higgs field is so inextricably jumbled with the weak force, that until now we've been unable to confirm its actual and independent existence.
JG: Or here's a video that I made as part of my show "Crash Course," talking about World War I: (Video) The immediate cause was of course the assassination in Sarajevo of the Austrian Archduke Franz Ferdinand, on June 28, 1914, by a Bosnian-Serb nationalist named Gavrilo Princip.
Quick aside: It's worth noting that the first big war of the twentieth century began with an act of terrorism.
So Franz Ferdinand wasn't particularly well-liked by his uncle, the emperor Franz Joseph -- now that is a mustache!
But even so, the assassination led Austria to issue an ultimatum to Serbia, whereupon Serbia accepted some, but not all, of Austria's demands, leading Austria to declare war against Serbia.
And then Russia, due to its alliance with the Serbs, mobilized its army.
Germany, because it had an alliance with Austria, told Russia to stop mobilizing, which Russia failed to do, so then Germany mobilized its own army, declared war on Russia, cemented an alliance with the Ottomans, and then declared war on France, because, you know, France.
(Laughter) And it's not just physics and world history that people are choosing to learn through YouTube.
Here's a video about abstract mathematics.
(Video) So you're me, and you're in math class yet again, because they make you go every single day.
And you're learning about, I don't know, the sums of infinite series.
That's a high school topic, right?
Which is odd, because it's a cool topic, but they somehow manage to ruin it anyway.
So I guess that's why they allow infinite series in the curriculum.
So, in a quite understandable need for distraction, you're doodling and thinking more about what the plural of "series" should be than about the topic at hand: "serieses," "seriese," "seriesen," and "serii?"
Or is it that the singular should be changed: one "serie," or "serum," just like the singular of "sheep" should be "shoop."
But the whole concept of things like 1/2 + 1/4 + 1/8 + 1/16 and so on approaches one, is useful if, say, you want to draw a line of elephants, each holding the tail of the next one: normal elephant, young elephant, baby elephant, dog-sized elephant, puppy-sized elephant, all the way down to Mr. Tusks and beyond.
Which is at least a tiny bit awesome, because you can get an infinite number of elephants in a line, and still have it fit across a single notebook page.
JG: And lastly, here's Destin, from "Smarter Every Day," talking about the conservation of angular momentum, and, since it's YouTube, cats: (Video) Hey, it's me, Destin.
Welcome back to "Smarter Every Day."
So you've probably observed that cats almost always land on their feet.
Today's question is: why?
Like most simple questions, there's a very complex answer.
For instance, let me reword this question: How does a cat go from feet-up to feet-down in a falling reference frame, without violating the conservation of angular momentum?
(Laughter) JG: So, here's something all four of these videos have in common: They all have more than half a million views on YouTube.
And those are people watching not in classrooms, but because they are part of the communities of learning that are being set up by these channels.
And I said earlier that YouTube is like a classroom to me, and in many ways it is, because here is the instructor -- it's like the old-fashioned classroom: here's the instructor, and then beneath the instructor are the students, and they're all having a conversation.
And I know that YouTube comments have a very bad reputation in the world of the Internet, but in fact, if you go on comments for these channels, what you'll find is people engaging the subject matter, asking difficult, complicated questions that are about the subject matter, and then other people answering those questions.
And because the YouTube page is set up so that the page in which I'm talking to you is on the exact -- the place where I'm talking to you is on the exact same page as your comments, you are participating in a live and real and active way in the conversation.
And because I'm in comments usually, I get to participate with you.
And you find this whether it's world history, or mathematics, or science, or whatever it is.
You also see young people using the tools and the sort of genres of the Internet in order to create places for intellectual engagement, instead of the ironic detachment that maybe most of us associate with memes and other Internet conventions -- you know, "Got bored.
Invented calculus."
Or, here's Honey Boo Boo criticizing industrial capitalism: ["Liberal capitalism is not at all the Good of humanity.
Quite the contrary; it is the vehicle of savage, destructive nihilism."]
In case you can't see what she says ... yeah.
I really believe that these spaces, these communities, have become for a new generation of learners, the kind of communities, the kind of cartographic communities that I had when I was in high school, and then again when I was in college.
And as an adult, re-finding these communities has re-introduced me to a community of learners, and has encouraged me to continue to be a learner even in my adulthood, so that I no longer feel like learning is something reserved for the young.
Vi Hart and "Minute Physics" introduced me to all kinds of things that I didn't know before.
And I know that we all hearken back to the days of the Parisian salon in the Enlightenment, or to the Algonquin Round Table, and wish, "Oh, I wish I could have been a part of that, I wish I could have laughed at Dorothy Parker's jokes."
But I'm here to tell you that these places exist, they still exist.
They exist in corners of the Internet, where old men fear to tread.
(Laughter) And I truly, truly believe that when we invented Agloe, New York, in the 1960s, when we made Agloe real, we were just getting started.
Thank you.
(Applause)