[Pages 13- in print version. © the Johns Hopkins University Press 1992].
Writers on hypertext trace the concept to a pioneering article by Vannevar Bush in a 1945 issue of Atlantic Monthly, that called for mechanically linked information-retrieval machines to help scholars and decision makers faced with what was already becoming an explosion of information. Struck by the "growing mountain of research" that confronted workers in every field, Bush realized that the number of publications has already "extended far beyond our present ability to make real use of the record. The summation of human experience is being expanded at a prodigious rate, and the means we use for threading through the consequent maze to the momentarily important item is the same as was used in the days of square-rigged ships" (17-18). As he emphasized, "there may be millions of fine thoughts, and the account of the experience on which they are based, all encased within stone walls of acceptable architectural form; but if the scholar can get at only one a week by diligent search, his syntheses are not likely to keep up with the current scene" (29).
According to Bush, the main problem lies with what he termed "the matter of selection" -- information retrieval -- and the primary reason that those who need information cannot find it lies in turn with inadequate means of storing, arranging, and tagging information:
Our ineptitude in getting at the record is largely caused by the artificiality of systems of indexing. When data of any sort are placed in storage, they are filed alphabetically or numerically, and information is found (when it is) by tracing it down from subclass to subclass. It can be in only one place, unless duplicates are used; one has to have rules as to which path will locate it, and the rules are cumbersome. Having found one item, moreover, one has to emerge from the system and re-enter on a new path. (31)
As Ted Nelson, one of Bush's most prominent disciples, points out, "there is nothing wrong with categorization. It is, however, by its nature transient: category systems have a half-life, and categorizations begin to look fairly stupid after a few years. . . . The army designation of 'Pong Balls, Ping' has a certain universal character to it" (Literary Machines , 2/49).
In contrast to the rigidity and difficulty of access produced by present means of managing information based on print and other physical records, one needs an information medium that better accommodates to the way the mind works. After describing present methods of storing and classifying knowledge, Bush complains, "The human mind does not work that way" ("As We May Think," 31) but by association. With one fact or idea "in its grasp," the mind "snaps instantly to the next that is suggested by the association of thoughts, in accordance with some intricate web of trails carried by the cells of the brain" (32).
To liberate us from the confinements of inadequate systems of classification and to permit us to follow natural proclivities for "selection by association, rather than by indexing," Bush therefore proposes a device, the "memex," that would mechanize a more efficient, more human, mode of manipulating fact and imagination. "A memex," he explains, "is a device in which an individual stores his books, records, and communications, and which is mechanized so that it may be consulted with exceeding speed and flexibility. It is an enlarged intimate supplement to his memory" (32). Writing in the days before digital computing (the first idea for a memex came to him in the mid-1930s), Bush conceived of his device as a desk with translucent screens, levers, and motors for rapid searching of microform records. [Since I wrote this discussion of Bush's memex, Paul Kahn and Ian Adelman have created a sound-enhanced animation of the device, which you can download from another site.]
In addition to thus searching and retrieving information, the memex also permits the reader to "add marginal notes and comments, taking advantage of one possible type of dry photography, and it could even be arranged so that he can do this by a stylus scheme, such as is now employed in the telautograph seen in railroad waiting rooms, just as though he had the physical page before him" (33). Two things demand attention about this crucial aspect of Bush's conception of the memex: First, he believes that while reading, one needs to append one's own individual, transitory thoughts and reactions to texts. With this emphasis Bush in other words reconceives reading as an active process that involves writing. Second, his remark that this active, intrusive reader can annotate a text "just as though he had the physical page before him" recognizes the need for a conception of a virtual, rather than a physical, text. One of the things that is so intriguing about Bush's proposal is the way he thus allows the shortcomings of one form of text to suggest a new technology, and that leads, in turn, to an entirely new conception of text.
The "essential feature of the memex," however, lies not only in its capacities for retrieval and annotation but also in those involving "associative indexing" -- what present hypertext systems term a link -- "the basic idea of which is a provision whereby any item may be caused at will to select immediately and automatically another" (34). Bush then provides a scenario of how readers would create "endless trails" of such links:
When the user is building a trail, he names it, inserts the name in his code book, and taps it out on his keyboard. Before him are the two items to be joined, projected onto adjacent viewing positions. At the bottom of each there are a number of blank code spaces, and a pointer is set to indicate one of these on each item. The user taps a single key, and the items are permanently joined. In each code space appears the code word. Out of view, but also in the code space, is inserted a set of dots for photocell viewing; and on each item these dots by their positions designate the index number of the other item. Thereafter, at any time, when one of these items is in view, the other can be instantly recalled merely by tapping a button below the corresponding code space. (34)
Bush's remarkably prescient description of how the memex user creates and then follows links joins his major recognition that trails of such links themselves constitute a new form of textuality and new form of writing. As he explains, "when numerous items have been thus joined together to form a trail . . . It is exactly as though the physical items had been gathered together from widely separated sources and bound together to form a new book." In fact, "it is more than this," Bush adds, "for any item can be joined into numerous trails" (34), and thereby any block of text, image, or other information can participate in numerous books.
These new memex books themselves, it becomes clear, are the new book, or one additional version of the new book, and, like books, these trail sets or webs can be shared. Bush proposes, again quite accurately, that "wholly new forms of encyclopedias will appear, ready-made with a mesh of associative trails running through them, ready to be dropped into the memex and there amplified" (35). Equally important, individual reader-writers can share document sets and apply them to new problems.
Bush, an engineer interested in technical innovation, provides the example of a memex user
studying why the short Turkish bow was apparently superior to the English long bow in the skirmishes of the Crusades. He has dozens of possibly pertinent books and articles in his memex. First he runs through an encyclopedia, finds an interesting but sketchy article, leaves it projected. Next, in a history, he finds another pertinent item, and ties the two together. Thus he goes, building a trail of many items. Occasionally he inserts a comment of his own, either linking it into the main trail or joining it by a side trail to a particular item. When it becomes evident that the elastic properties of available materials had a great deal to do with the bow, he branches off on a side trail which takes him through textbooks on elasticity and tables of physical constants. He inserts a page of longhand analysis of his own. Thus he builds a trail of his interest through the maze of materials available to him. [34-35]
And, Bush adds, his researcher's memex trails, unlike those in his mind, "do not fade," so when he and a friend several years later discuss "the queer ways in which a people resist innovations, even of vital interest" (35), he can reproduce his trails created to investigate one subject or problem and apply them to another.