In our hypermodern times it looks like that the answer to what something is lies a click or a thought away, somewhere between “Ask Google” and “I don’t need Google, my wife knows everything.”
But, really, what defines a thing, a person or a place?
Is it its definition alone, or is it the words used to signify it? Could that be its visual representation? Or perhaps all the factual data that, say, Wolfram Alpha (a computational knowledge engine) renders for it?

Or maybe it’s the information START, the world’s first Web-based question answering system, gives when asked?

Also it could be that looking for a description itself is a wrong way to try to define things. We might succeed in defining a chair not by using the features or the facts about it, but rather its function, i.e. its purpose. As quoted in a paper, called What Makes a Chair a Chair?:
There’s little we can find in common to all chairs – except for their intended use.
cit. Minsky, 1986, [16, p. 123]
Fortunately, because of the dynamic and interactive essence of things, from whatever perspective we try to answer the above posed questions, there can never be an ultimate answer, not unless some kind of controversy, disambiguation or even a paradox has stepped in and been tolerated.
It’s just how the couple sign:object and the open (signifying) systems work.
Time travelling for a quick visit to the museum: One and Three chairs
Speaking of essence, meaning and disambiguation, let’s approach the subject of definition and representation via a piece of conceptual art from the 60s and set off on a quick time travel journey.

The work on the picture above is called One and Three Chairs and is a piece of art created by the American conceptual artist Joseph Kosuth in 1965. This work is seen to highlight the relation between language, picture and referent, problematizing the correspondence between idea, object, visual and verbal references.
As controversial and difficult to define conceptual art might be, it’s a good sample for exploring the issue with the ambiguity of things, their signifiers, essence and purpose.
It is exactly in such a semiotic quest for meaning (in which conceptual art has embarked numerous times) that the relation interpreter-interpreted gains momentum and one more time shows that any signifying system fails at trying to unambiguously describe an object.
Again, it appears that you just can’t represent something unambivalently.
Unless you can.
Enter the Semantic Web
The Semantic Web was outlined by Tim Berners-Lee, one of the founders of the World-Wide Web and a director of the W3C (World Wide Web Consortium), at the International Conference XML-2000, held in Washington back in 2000 (see Berners-Lee and the Semantic Web Vision by Edd Dumbill).
The concept of the Semantic Web as a place where unified structured data is being communicated, exchanged and integrated with real world objects is seen as the next stage in the development of Internet. (I owe this last short summary to Dimo Belov; the slides from the above-mentioned presentation are available here: Semantic Web on XML).
But how can information be unified and structured, provided the world and the languages (verbal, visual and other) through which we perceive it are ambiguous by default?
At its core the semantic web is about relations: bits of information related to other bits. To cite an excerpt from David Amerland’s Google Semantic Search:
[The Knowledge Graph] means a group of linked data nodes, not only facts [i.e. data nodes] but also data about how these data nodes are connected to each other and what the connections actually mean.
cit. Google Semantic Search, p. 22
To get back to the museum for a second, if conceptual art searches for meaning outside the referenced objects which it does not necessarily represent (for the concepts behind Conceptual art see One and Three Ideas: Conceptualism Before, During, and After Conceptual Art), the Semantic Web does not deal with the question of what is directly, it rather defines objects (entities) by not looking for their essence within, but for the external objects (entities) and values they are linked to.
The problem of ambiguity of language, of names “and of other common properties, makes determining which entity a document is referring to a difficult task” (cit. Google On Finding Entities: A Tale Of Two Michael Jacksons), but is solved by ontologies (collections of meaning).

In the semantic web the answer to the question “What is something?” depends on the context of the query, who, when, where and what for asks. Of course, that does not mean that for different people the definition of one and the same thing is different, it only means that definition, representation and description are highly utilitarian by design.
In the pre-semantic web a thing was represented in a way literally, only by what signified the object in question, a bit like the work One and Three Chairs: abstract, devoid of relationships, a frozen construct, signified in a too narrow way.
In the age of semantic search things have changed. As Gianluca Fiorelli put it in his article From Semantic to Semiotic. The next evolution of Search Marketing:
With the continuous effort Google is making in transitioning from an Internet of Strings (just based on the signifiers) to an Internet of Things (entities, both named and search ones, or signified in Semantics jargon), we should soon need to talk of the passage from Semantics to Semiotics in Search.
Now the representation of something is not only its signifier (say an image or a word definition); it is represented by its concept, through entities and more importantly, thorough the relationships between them.
What defines something is outside of it, defined by the context of its existence and most importantly by the purpose it serves. Any definition is meaningful in the light of three main concepts for the Semantic Web: personal assistant, IoT, information retrieval. Ambiguity is resolved by the goal the definition serves.
One and Three Ideas: Automatization of Information Retrieval, Internet of Things, Personal Assistant
When it comes to the Semantic Web the question of defining and representing is a matter of execution, rather than “ontological” debate on essence.
For the unstructured (that is undefined, not described with meta information) data on the Web to start making sense and be able to convey meaning to different agents (not only humans) it needs “an extension […] in which information is given well-defined meaning, better enabling computers and people to work in cooperation” (cit. Tim Berners-Lee, The Semantic Web A new form of Web content that is meaningful to computers will unleash a revolution of new possibilities, 2001). This extension is the Semantic Web.
The Semantic Web will bring structure to the meaningful content of Web pages, creating an environment where software agents roaming from page to page can readily carry out sophisticated tasks for users,
writes Tim Berners-Lee.
The structure that the Semantic Web will give to the unrelated information on the Web will serve three main purposes:
- AUTOMATIZATION OF INFORMATION RETRIEVAL
- INTERNET OF THINGS
- PERSONAL ASSISTANT
The above listed items have been summarised from the cited article by Tim Berners-Lee. There you can follow the idea behind the Semantic Web from the perspective of its practical applications.
A thing is defined by its relationships
It is true that the world and the languages describing it are complex open systems, dynamic by nature and prone to ambiguity. But, again, a semantic search within a knowledge-representation system would look at all the relationships between a query, the querier and the available information and how all these blend together in an attempt to extract meaning for a certain situation.
At the end of the day, it’s the relationships that will be the key to describing something and getting to the greatest extent possible closer to it so that it makes sense and can be used to feed greater goals (and/or higher conceptual levels).
The sense of the world must lie outside the world
Language and sign systems are a contract. We not only use definitions and interact with them, but also alter, deprecate and renew them. Thus the question of representation and definition appears to be more a question of connections and shared meaning.
In his Tractatus Logico-Philosophicus Witgenstein wrote:
The sense of the world must lie outside the world
He also stated:
2.01 An atomic fact is a combination of objects (entities, things).
2.011 It is essential to a thing that it can be a constituent part of an atomic fact.
cit. Tractatus Logico-Philosophicus, by Ludwig Wittgenstein, 6.42
Somewhat similarly, in the semantic web, relationships between things, people and places, on all levels are key to understanding and proper communication (between people, software and hardware). This constant information exchange will not only call for shared language (both human and machine) but also for creating and keeping transparent, mappable relationships.
In a word, for their perpetual poiesis and experiencing.
Above all, the answers to both the question of definition and the question of relationships appear not to be goals but paths. Just like the relationship (and my attempt to map it) between the Semantic Web and conceptual art was.