In their Reinventing Knowledge chapter on monasteries and convents, Ian McNeely and Lisa Wolverton mention findability techniques developed following the invention of the page, including alphabetical order (p. 91). David Weinberger, in Everything Is Miscellaneous, also discusses the development of alphabetical order in the Middle Ages. He points out that it took a long time tocatch on because, in his opinion, it was “conceptually confusing.” To prove his point about confusion, he quotes alphabetizing instructions from 1286, which apart from the funny spelling, are actually quite clear (pp. 26-27). Weinberger is correct, however, that alphabetical order took centuries to be accepted, but he is wrong about the reason. It was not too confusing, it was too easy.
According to Mary and Richard Rouse in their article “Statim invenire: Schools, Preachers, and New Attitudes to the Page,”* the alphabet is an artificial method of ordering as opposed to a rational method. This distinction can be seen in glosses, reference works that explained details of the Bible without biblical interpretation. These glosses eventually evolved into glossaries. Information in early glosses appeared in the same order that it appeared in the Bible or other religious books. This is called a rational order. Even indexes were arranged in the same order as the book being indexed. To find something, you had to already know what page it was on. Rouse & Rouse indicate these early finding devices were meant to reflect the concept that the “universe is a harmonious whole” (p. 202). So the primary concern of arrangement was to promote philosophy not to find information.
That changed when authors of religious books needed streamlined access to information. As preachers, they started alphabetizing material called distinction collections to help them prepare weekly, or in 1200 perhaps daily, sermons. Alphabetical order is an artificial method because it has no purpose other than to arrange information. It does not reflect how the book is organized. It does not reflect a philosophical theory. It just puts material into a simple, easy to understand structure. The preachers apologized for using alphabetical order, but they went ahead and developed the method because they needed to find information fast.
The controversy over alphabetical order continues today. An information architecture discussion list recently had a lively exchange about popularity ranking vs. the alphabet. One person preferred popularity because it was felt that alphabetical order is essentially random. The respondent here was confusing an artificial arrangement with a complete lack of order. More interesting, however, is the assumption that a rational order with unknown values, such as popularity, is preferable to an artificial order with known values, such as the alphabet. We pretty much all know the alphabet, but if you look at a list of items arranged by popularity, you can only guess at individual placement.
Function determines the form of an arrangement. Popularity and the alphabet serve different functions. There are many situations where popularity is the most valuable organizing choice. But if you just want to display information for fast location, those preachers in the Middle Ages developed a very easy method.
* The Rouse and Rouse article is available as a chapter in their book Authentic Witnesses: Approaches to Medieval Texts and Manuscripts (1991) and in the conference proceedings Renaissance and Renewal in the Twelfth Century (Robert L. Benson and Giles Constable, eds., 1982).