Ergodic literature is a mode of textual organization in which nontrivial effort is required for the reader to traverse the text, beyond ordinary eye movement or turning pages. Espen J. Aarseth appropriated the term from physics, deriving it from the Greek ergon (âÂÂworkâÂÂ) and hodos (âÂÂpathâÂÂ). He introduced the term within his broader concept of cybertext, which he presents not as a literary genre but as a perspective on textual machines that compute or permute outputs. In AarsethâÂÂs framing, the cybertextual process includes a semiotic sequence produced through the userâÂÂs material actions, which conventional notions of âÂÂreadingâ do not fully capture. Although frequently compared to âÂÂnonlinearityâ in physics, Aarseth treats such nonlinearity in hypertext as a topological, graph-theoretic property of nodes and links rather than a concept imported from physics.
Aarseth's book contains the most commonly cited definition of ergodic literature:
<blockquote>In ergodic literature, nontrivial effort is required to allow the reader to traverse the text. If ergodic literature is to make sense as a concept, there must also be nonergodic literature, where the effort to traverse the text is trivial, with no responsibilities placed on the reader except (for example) eye movement and the periodic or arbitrary turning of pages.</blockquote>
His aim in providing this definition is to offer a radical break from earlier theories of Hypertext, which he says fall trap to 'an essentialist idea of "the computer medium" as a singular structure of well-defined properties,' and thus remain blind both to the plurality of types of media that a computer can support, and of the forms that text can take outside of a digital medium. Additionally, without free text search, many hypertext works end not less, but more linear than the conventional codex, in stark contrast with the technoutopist visions of hypertext and its capabilities. To this end, he aims to develop a model of literature organised not around the medium in which the work is contained, but instead around the manner in which the text itself functions and interacts with its reader.
Aarseth divides the text into three core constituent elements: the medium itself, the human operator, and the strings of signs which make up the text itself. The last of these he divides into two distinct categories: textons â strings of signs as they appear (or are encoded) in the text itself â and scriptons â strings of signs as they appear to the reader or user of the text. From there, Aarseth develops a typology of possible media positions for texts, organised around seven axes:
These seven variables are capable of producing a total of 576 unique media positions (3 x 2 x 2 x 2 x 2 x 3 x 4), of which conventional hypertext and literature represent only a small part. Among these, Aarseth defines an 'ergodic text' as any one which requires at least one of the three other user functions beyond mere interpretation. Thus, both paper-based and electronic texts can be ergodic: "The ergodic work of art is one that in a material sense includes the rules for its own use, a work that has certain requirements built in that automatically distinguishes between successful and unsuccessful users."
Cybertext is AarsethâÂÂs perspective on dynamic textual machines; he proposes reserving âÂÂcybertextâ for texts where âÂÂcalculationâ produces scriptons. Thus, works of hypertext fiction of the simple node and link variety may be ergodic literature but not cybertext: it is the presence of conditional links and computation that shift them toward being cybertext. A chat bot such as ELIZA is considered a cybertext because when the reader types in a sentence, the text-machine actually calculates directly based on the user's input to generate a textual response. Likewise, the I Ching is cited as an example of cybertext: though it is the reader that carries out the calculation, the rules to generate responses are clearly embedded in the text itself.
It has been argued that these distinctions are not entirely clear and scholars still debate the fine points of the definitions. The concepts of cybertext and ergodic literature were of seminal importance to new media studies, in particular literary approaches to digital texts and to game studies.
Cybertext has also been suggested as a tool to enhance learner engagement and motivation in language education.
Aarseth gives two major lists of examples of ergodic literature throughout the work â first in the opening chapter, then in the third, where a possible typology is discussed. The major examples listed throughout the work include:
There are still further examples worth considering, however, especially ones that came out after Cybertexts release, or were simply too obscure or glanced over at the time of release. Such include: