Architecture of theWorld WideWeb - Social Semantics: The Search for Meaning on the Web - page 34

want to identify in and of themselves, being by definition the response of a server to
a particular response and request for information. While one could imagine wanting
to access a particular Web representation, in reality what is usually wanted by the
user-agent is the content of the resource, which may be present in a wide variety of
languages. What is important is that the sense gets transferred and interpreted by the
user agent, not the individual bytes of a particular encoding in a particular language
at a particular time.

2.2.5 Digitality

The Web is composed of not just representations, but digital representations. One
of the defining characteristics of information on the Web is that this information is
digital, bits and bytes being shipped around by various protocols. Yet there is no
clear notion of what 'being' digital consists of, and a working notion of digitality
is necessary to understand what can and can not be shipped around as bytes on the
Web. Much like the Web itself, we can know something digital when we spot it, and
we can build digital devices, but developing an encompassing notion of digitality is
a difficult task, one that we only characterize briefly here.
Goodman defined marks as “ finitely differentiable ” when it is possible to deter-
mine for any given mark whether it is identical to another mark or marks (Goodman
1968). This can be considered equivalent to how in categorical perception, despite
variation in handwriting, a person perceives hand-written letters as being from a
finite alphabet. So, equivalence classes of marks can be thought of as an application
of the philosophical notion of types . This seems close to 'digital,' so that given
a number of types of content in a language, a system is digital if any mark of
the encoding can be interpreted to one and only one type of content. Therefore,
in between any two types of content or encoding there cannot be an infinite
number of other types. Digital systems are the opposite of Bateson's famous
definition of information: Being digital is simply having a difference that does not
make difference (Bateson 2001). This is not to say there are characteristics of a
mark which do not reflect its assignment in a type, and these are precisely the
characteristics which are lost in digital systems. So in an analogue system, every
difference in some mark makes a difference, since between any two types there is
another type that subsumes a unique characteristic of the token. In this manner,
the prototypical digital system is the discrete distribution of integers, while the
continuous numbers are the analogue system par excellence, since between any real
number there is another real number.
Lewis took aim at Goodman's interpretation of digitality in terms of determinism
by arguing that digitality was actually a way to represent possibly continuous
systems using the combinatorics of discrete digital states (1971). To take a less
literal example, discrete mathematics can represent continuous subject matters. This
insight caused Haugeland to point out that digital systems are always abstractions
built on top of analog systems (1981). The reason we build these abstractions is