In its nearly nine years of existence, Twitter has grown to encompass an array of communities and subgenres. There’s media Twitter, weird Twitter, black Twitter, dad Twitter, and brand Twitter—each with distinct and overlapping references and formats. Joke formats, in particular, tend to ripple across networks in waves. One day, bae is everywhere. The next, it's all about the sign bunny.

As people continue to develop a sort of collective literacy of the tweet as a narrative form, Twitter’s uses and styles are evolving into an entirely new dialect.

Except maybe it’s not entirely new. While the platform has created new subtextual categories for communicating, Twitter often showcases classic philosophical theories of humor in action. In other words, the platform is new but the narrative structure is ancient.

For thousands of years theorists have attempted to group together the contextual elements that make a situation funny. The philosophical theories of humor explain the conditions that provoke laughter, often in relation to other human emotions.

It’s no surprise that the three longest standing theories of humor—Superiority Theory, Relief Theory, and Incongruity Theory—are all over the funny side of Twitter.

Superiority Theory can be traced through generations of philosophers, all of whom were convinced that laughter is rooted in dislike or ill-will, and is a physical expression of having the upper hand in a situation. In his 1651 book Leviathan, the English philosopher Thomas Hobbes explains laughter as the physical representation of sudden glory:

Sudden glory is the passion which maketh those grimaces called laughter; and is caused either by some sudden act of their own that pleaseth them; or by the apprehension of some deformed thing in another, by comparison whereof they suddenly applaud themselves.

Consider Hobbes' theory as it applies in a tweet like the one below.

This joke works on a couple of levels, which require the reader to understand several cultural references. There's ridicule of crafty workarounds called “life hacks.” Not only do you have to know what a life hack is, but also that Maroon 5 is a band and Adam Levine is its frontman. Finally, you have to understand that the whole thing is a fictional vignette in the tweeter's mind. Pithy, referential jokes are king when it comes to Superiority Theory on Twitter, because the sudden glory is often hidden between the lines.

The second common theory, Relief Theory, assumes that laughter is the necessary physical release of emotion. In support of this idea, Sigmund Freud described humor as the expulsion of surplus energy—often nervousness or anxiety. Joke tweets that follow Relief Theory are based on the writer’s ability to build the pressure of emotion quickly. Twitter's 140-character limit has encouraged humorous micro-stories this way.

The above tweet teases with the promise of an answerable question and, according to relief theory, the resulting humor comes from the experience of expecting something more serious than you end up with. This shift in storytelling style is motivated by Relief Theory, and can work in the other direction, too. The tweet below begins with a lighthearted tone but ends on a darker note:

Jokes that illustrate Relief Theory are all over Weird Twitter, where character-driven absurdist vignettes are standard. One of the most retweeted such jokes started an entire subgenre of "cop starts breakdancing" tweets, though there's some controversy about its original author:

As with many joke formats on Twitter, as the website Joke Anatomy put it, "Someone’s always completely out of the loop; someone else is sick of hearing about it already."

Finally, Incongruity Theory shares the principle of surprise with Relief Theory, but focuses on the cognitive process instead of the physical release. The influential German philosopher Immanuel Kant considered humor to be a stimulating juxtaposition, or a shifting of ideas similar to a playing a game or enjoying music. Other theorists that have described humor as incongruous reasoned that it comes from the disruption of a pattern that the mind had expected to continue. Perhaps the most recent and widespread example of Twitter humor being lost in translation came in the form of incongruous tweets sent in reaction to Kanye West and Paul McCartney’s musical collaboration.

As more and more people retweeted this tweet, news outlets like BuzzFeed, E! and Good Morning America used it and similar tweets as indication that some Kanye West fans had never heard of The Beatles. What these outlets missed was the juxtaposition between an abstract concept (Kanye West as a culture tastemaker) and a physical representation (Paul McCartney, an already famous musician). The joke works because the reader can easily follow the first idea, but is then caught off guard by what seems to be supporting evidence. The humor is in the disconnect.

Incongruity Theory on Twitter encourages misunderstandings because the jokes are so often framed like basic observational tweets. Twitter was originally lauded as a place to share everyday updates and to make illustrative observations. Despite its evolution into a multi-faceted communication source, the completely botched representation of a joke like this shows that a lot of people still only consider tweets to be capable of one thing at a time. (And people have been telling jokes on Twitter since almost the very beginning of the platform.)

Of course, picking up on contextual cues is the key to getting a joke in any format. The difference with Twitter is that tweets are individually packaged and audiences aren’t well defined. So the way humor is experienced on Twitter is up to the person scrolling through tweets—rather than the person doing the tweeting. Another way to think about this: When a person walks into a comedy club, she can expect to hear jokes. And the comedians onstage know they are telling jokes to an audience of clued-in people who understand they’re at a comedy club. On Twitter, where someone might expect one thing and get another, that basic contextual framework evaporates.

Linking philosophical theories of humor to months-old tweets makes it clear that the reasons we’re laughing aren’t changing, only the presentation of the ideas that we’re laughing at. Twitter’s concise, limited-context style is unusual in other communication formats, which helps explain why it can be so hard to get the joke.