Subtitles section Play video Print subtitles Here's an idea-- "Adventure Time" is popular because of nostalgia. (THEME MUSIC) "Adventure Time"-- come on and grab your friends-- is a kids' television show on the Cartoon Network. It stars Jake the Dog and Finn the Human and was created by bearded human Pendleton Ward, pictured here wearing some awesome glasses. It's set in the magical land of Ooo and its many kingdoms which are home to Candy People, animals, and a whole cast of generally weird but also adorable characters. My personal favorite is the Shnow Golem. As one might suspect, the general thrust of "Adventure Time" is adventures. Finn and Jake are best buds who go on all manner of moral, ethical, and totally and totally mathematical escapades. Finn, you're terrible at math. Aww. They rescue princesses, fight giant monsters, protect the innocent, and have a strong dislike of evil dudes. And they are very popular, amongst not only kids, but also a huge contingent of honest-to-Glob growed-up adults. Now if you're a kid, "Adventure Time" probably looks a lot like the inside of your head-- exciting sights, magical objects, and impossibly terrifying things. But if you're an adult, "Adventure Time" is like remembering your childhood. Fighting to be taken seriously, constant encounters with new and unfamiliar challenges, grappling with a deer that has hands. Creepy. For many adults, the core appeal of "Adventure Time" is its nostalgia. Not like Instagram filters or cassette tapes post-irony nostalgia, but more like classical nostalgia, a pain of an ache for a time past that you can't recreate. While we usually think of its roots as in culture or the arts, nostalgia was actually born in 1688 as a medical diagnosis for Swiss soldiers wishing to return home. It's this wily emotion that's a mix of good and bad. At the same time that you're fondly remembering something, you're also confronted with the fact that it's gone, or unattainable. From its origins, nostalgia weaseled its way into everything from art to politics to industrial design. You name it, someone thinks that the thing that came before it was better. Along the way, it transformed from medical nostalgia into poetic or romantic nostalgia, from a disease that could be cured with leeches to a feeling that could be evoked-- by a young kid in an animal hat. In "Nostalgia of the Future," Svetlana Boym writes, "The object of romantic nostalgia must be beyond the present space of our experience, somewhere in the twilight of the past or on an island of Utopia, where time has happily stopped, as on an antique clock." I can definitely remember a twilight of the past with imaginary friends, treehouses, magical weapons, and if given the chance, I'd happily stop there. "Adventure Time" is perfectly, romantically nostalgic for childhood. But so are a lot of other shows, like "Foster's Home for Imaginary Friends," "The Amazing Adventures of Gumball," and even "Rugrats," sort of. What is it about "Adventure Time" that makes it so well-liked, especially by not-kids? Here's where it gets a little complicated. It's because at the same time we the audience are experiencing nostalgia, so too are the characters in "Adventure Time." It's nostalgia within nostalgia. It's a "nostalgia-ception." Take a look at some of the clues. There was a mysterious devastating mushroom war. A lot of the characters, especially Marceline and the Ice King, have this unexplained evolving "wish it were still the good old days" past. The landscape is littered with human remains and technology. And in certain episodes, you can even see a partially destroyed planet Earth in the sky. I mean, Finn is the last human, for Glob's sake. That is, unless Susan Strong isn't a fish, and you count the Ice King as-- uh, uh, never mind. "Adventure Time" is a fun, adventurous kids' show with a history, a potentially very dark history. Pen Ward has even said his favorite emotion is feeling simultaneously happy and sad. So that's a reaction he tries to elicit in "Adventure Time." This is called ambivalence, and it's what's at the root of nostalgia. It means you're holding onto two usually conflicting emotions at the same time. And "Adventure Time" does it on two levels. So that's four total emotions, for the folks keeping track at home. You see it in the settings and the relationships, but also in the cute but disturbing creatures, the comedic but dire situations, the childlike but nonetheless high-stakes situations. It's in the show, but it's also experienced by the audience. All these things contribute to capital-D Drama. Not like lowercase-D drama, which is what LSP gets herself involved in. Yo, guess what? Slime Princess is in the park, and she's, like, talking to a new Nice King. Uh, and he's like, totally single. Which by itself definitely doesn't make a good show, but combined with the creator's amazing imagination and character design, makes maybe the best animated show ever. I'm biased. I really like "Adventure Time." But seriously, I know more adults than kids who watch "Adventure Time," including my mom. So that has to mean something. Yes, adults watch cartoons, but that's not the interesting part. The interesting part is that most of the cartoons adults watch are made for adults. "The Simpsons," "Bob's Burgers," "Family Guy," "South Park," even most anime-- adult situations, adult humor, and maybe with the exception of anime, very little emotional depth. But man, when Finn hugs the Flame Princess wrapped up in a tin-foil burrito? It's too much. It's just-- it's just too much. "My Little Pony" is maybe the only other close comparison, but its popularity is because of a whole other thing-- that we talk about in a video that you should watch. "Adventure Time" is maybe the closest television comes to classic fairy tales, exhibiting a combo of terror and humor, excitement and fear, that are the very hallmarks of childhood. Or maybe I just have a playground crush on Marceline. What do you guys think? Does "Adventure Time" make you kind of sad, and is that why you like it? Let us know in the comments. And if you're feeling ambivalent about subscribing, you could just subscribe. Or not. Whatever. Yes, I grew a silly mustache. Let's see what you guys had to say about YouTube and education. We were really lucky to hear from Brady of Periodic Videos fame about last week's episode. He sent us this clip. Hey there, Mike. I saw your video. It's so hard to measure or not whether YouTube is making people smarter. We all drown in viewing statistics, but what do they tell us? I'd like to show you some photos. This is Eddie from Arkansas, and his Christmas present was a signed photo from the scientists on the Periodic Videos channel. And this is Eduardo from Italy. His 10th birthday wish was to come to the University of Nottingham in England and meet his YouTube heroes. And we seem to have countless stories like this, new things coming up all the time. Now, this shows that these people are listening, they're really engaged. And if they're listening this closely, they must at least be on their way to learning. Thanks so much, Brady, for sending us that awesome clip. Mc7738 is a high-school biology teacher who says that YouTube is indispensable in the classroom, especially considering how dry a lot of the textbooks are. If my high school experience is any indication, that sounds-- that sounds about right. Euclids Paradox makes a really good point, that YouTube allows you to introduce yourself