Only six kinds of core emotional narratives make up literature, according to a study performed by a team of scientists at The University of Vermont, Science Alert reports.

Andrew Reagan at the Computational Story Lab, along with a few others, developed a computer program to analyze the “emotional arcs” of 1,700+ stories, which boiled down to the following types, as Peter Dockrill writes in Science Alert:

Rags to riches: “An ongoing emotional rise” (Alice’s Adventures Under the Ground)
Tragedy, or riches to rags: “an ongoing emotional fall” (Romeo and Juliet)
Man in a hole: “A fall followed by a rise”
Icarus: “A rise followed by a fall”
Cinderella: “Rise-fall-rise”
Oedipus: “Fall-rise-fall”

But this conclusion isn’t necessarily the ultimate one, as the MIT Technology Review points out, since the restricting variable was “the emotional polarity of ‘word windows,’” used to measure “how the emotional valence [of each story] changes,” and the “type” of narrative is particular to only that variable. Furthermore, the “method does not capture the changes in emotional polarity that occur at the level of paragraphs ... instead it captures the much broader emotional arcs involved in storytelling.” This also isn’t the same as, for example, grouping types by plot.

In addition, all the titles came from Project Gutenberg (a site that offers free access to over 50,000 books in the public domain), which means that most of the texts have been published before 1923; they’re also mainly fiction written in English, which rules out much literature that may not conform to these types.

That said, the results of the study form a foundation for more ambitious and detailed studies. For example, researchers found that the most downloaded stories at Project Gutenberg have the most complex emotional arcs—and that Cinderella and Oedipus arcs are the most downloaded of all the types.

Related news: Kurt Vonnegut was one of the first to portray the shapes of stories in graphical form, although Aristotle had done some of that work 2,000 years earlier.

Image Credit: Computational Story Lab.