The Evolving mSpace Platform:
Leveraging the Semantic Web on the Trail of the Memex
“Wholly new forms of encyclopedias will appear,
ready-made with a mesh of associative trails running through them” – V. Bush
mc schraefel, Daniel A. Smith, Alisdair Owens, Alistair Russell, Craig Harris, Max Wilson
IAM Group, Electronics and Computer Science
University of Southampton
Southampton UK
info @ mspace.fm http://mspace.fm

ABSTRACT
Vannevar Bush proposed the memex as a means to support
building knowledge in the way he says the human brain works: by
association. Achieving this vision has been a core motivation for
hypertext research. In this paper, we suggest first that Bush’s
memex reflects an interaction paradigm rather than system design.
Second, we propose that Semantic Web promises to provide the
mechanisms to enable these interaction requirements. Third, we
propose the mSpace framework and architecture as a platform to
deploy lightweight Semantic Web applications which foreground
associative interaction. We propose this lightweight approach as a
means to evaluate both interaction needs and the cost/benefits of
using Semantic Web technologies to support them.
Categories and Subject Descriptors
H.5.4 [Information Systems]: Hypertext/Hypermedia –
architectures, navigation, user issues.
General Terms
Design, Experimentation, Human Factors
Keywords
mSpace, hypertext, Bush, association, Semantic Web, memex
1. INTRODUCTION
There is a paradox to Web-based digital information systems:
when material is digitized it has the potential to become
simultaneously both more accessible and more invisible than it
ever was in its non-digital form. Digitized, its bits can be
transmitted effectively anywhere; digitized, it slips into the sea of
zeros and ones, indistinguishable. It depends utterly on both the
cues associated with it, and how those cues are represented in
order for it to be retrievable.
So far, the killer app of the Web has been the search engine: it lets
people search the content of the thing itself via keywords to get at
that thing directly. From the list of links returned by a search
engine, with its ever-improving algorithms for finding the most
likely match to a query, a person can trawl through increasingly
fewer dud links for the best match to their interest. In many ways,
the success of the search engine has shaped our expectations of
the Web. Modern browsers (a potentially anachronistic term)
reflect this: the “Google box” is either the default part of the
toolbar or is installed as a popular plug-in addition. But is
retrieval the best we can expect from the Web? Or is it that if all
we have is a search engine, everything we see is a nail?
The imagined next generation Web, the Semantic Web [4] has the
potential both simply to continue the Web-as-Google paradigm,
where the Semantic Web will make retrieval bigger, faster,
stronger (the Semantic Web as Bionic Web). But the Semantic
Web also has the potential to make take the Web closer towards
Hypertext [27, 30], specifically towards the memex, Vannevar
Bush’s vision of a machine that will support human-oriented
knowledge building by supporting a person’s construction of
associative links between one document and another.

Figure 1. View of mSpace Software Framework interface
mSpace is a project that uses Semantic Web technologies to
support such knowledge building. In this paper, we discuss the
motivation, design and architecture of the mSpace platform in
terms of its use of Semantic Web technologies for approaching
memex/hypertext goals. We first situate the discussion in a review
of Bush’s memex, and then describe mSpace in terms of its
interaction model, software framework and architecture. Our goal
in this is to put the approach and framework before the
community as one example of how hypertext research may inform
the evolution of the Semantic Web, and to demonstrate as a case
study in progress of some of the opportunities for hypertext
research when situated in the context of the Semantic Web.

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2. BACK TO BUSH
A founding motivating vision, not just for Hypertext researchers,
but for computer scientists, across disciplines [14, 34], has been
Vannevar Bush’s imagined memex[5]: a machine to hold all
digital information and which will allow rapid, easy associative
discovery of information and then path making from one
discovered resource to another, supporting the capture of a
person’s annotations on those resources along the way. Some
have predicted that we are close to achieving this vision [14], and
indeed, the Semantic Web holds the promise of providing the
technological underpinnings to enable that vision. It is then
worthwhile to go back to the original description of the memex to
remind ourselves of where we are with the Web relative to that
vision, and where we might aim with the Semantic Web.
As noted, keyword search is incredibly practical, useful and
effective. If we go back to the imaginary precursor of the Web,
however, we see that Bush is critical of the limitation of such
query systems. For him, being able to get at, use and extend “the
record” of knowledge is critical. As such, he identifies selection,
the finding of something useful, as one of the worst-served parts
of the knowledge-building process. He states,
The real heart of the matter of selection, however, goes
deeper than a lag in the adoption of mechanisms by libraries,
or a lack of development of devices for their use. Our
ineptitude in getting at the record is largely caused by the
artificiality of systems of indexing…The human mind does
not work that way. It operates by association. (All Bush
quotations are to [5])
That succinct quotation seemingly puts paid to any categorizing
system, from search engines to the Semantic Web that relies on
ontologies, classes and subclasses of relations. Bush proposes
instead what has become a well-known concept to hypertext
researchers, trail making: the ability to connect one thing to many
other things, including connections to one’s own annotations on a
thing of interest, potentially implicitly (or explicitly) creating
one’s own categorization structure on top of the system’s. These
trails are imagined as robust and sharable. It is the making of
these associative trails and their associated annotations that Bush
sees as the method by which one may not only “extend the
record” but makes it possible to consult it richly and effectively,
beyond what is possible even in a library. As Bush states,
A record, if it is to be useful to science, must be
continuously extended, it must be stored, and above all it
must be consulted…Even the modern great library is not
generally consulted; it is nibbled by a few... Thus far we
seem to be worse off than before - for we can enormously
extend the record; yet even in its present bulk we can hardly
consult it.
Bush proposes the memex as a solution to this problem.
2.1 Interaction before the “Artificial Index”
In the description of the memex, Bush founds its design on an
interaction problem rather than a mechanistic one. More
particularly, we might say he misdiagnoses an interaction problem
as a system problem. Let us look at more of the above passage:
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.
What Bush describes is the way he imagines people being forced
to interact with a system when the interaction mirrors the data
structure: if the data is stored in classes and subclasses on a graph,
then users must delve into classes and subclasses, coming up and
going down as required by the graph rather than by their
associative interests. Bush describes an interaction design as a
solution to the problem, and he does so with a technique that has
since become known as “scenario based design” [7].
The owner of the memex, let us say, is interested in the
origin and properties of the bow and arrow. Specifically he
is 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 [emphasis mine].
In the above passage, Bush describes not an architecture, but the
easy affordances of his system for tying items together, joining up
trails and adding annotations “through the maze of materials
available.” This interaction, Bush implies, is the antithesis to the
bumping about in disorienting subclasses of the “artificial index.”
But what feeds this interaction? There are certain assumptions
implicit in Bush’s description, both of the person’s search strategy
and the mechanisms that support it. Bush describes a person who
has a clear and identifiable interest: “the origin and properties of
the bow and arrow.” Second, the scientist has a research strategy:
“he runs through an encyclopedia” to find an article, and then
finds “a history.” He “branches off” but can come back to the
starting point and adds his own “longhand analysis.” Interestingly,
Bush assumes that the researcher uses more or less traditional
methods to start the search, with URL-like references: “These
sources [the encyclopedia and history] are referenced by the
“usual scheme of indexing.” Indeed, “if the user wishes to consult
a certain book, he taps its code on the keyboard…Frequently-used
codes are mnemonic.”
In today’s parlance of software engineering and human computer
interaction, we’d say that Bush describes an interaction layer for
his nemesis artificial index system; he does not get rid of that
underlying index, but imagines at least partially, a better, more
human way for the interaction layer to support the way the human
mind works, as Bush says, by association. Early Hypertext
systems from Nelson’s Xanadu [24] to Englebarts Augment [10]
to Intermedia [26] to Microcosm [9] recognized the value of the
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