Definite article and domain of discourse

Question

I am trying to understand a bit more about the mechanics of the definite article. Normally, we are taught that "the" picks out the object with certain properties or is used when we want to refer to a unique thing.

Examples of the first: The big book, the tall man etc

Example of the second: The Bible, The Earth's moon

It seems to me that this example of the first type are actually like that of second type but with restricted domain of discourse. For instance, if we consider all the people "who look tall" in the world, "the tall man" may not tell us much, and, if we consider "the tall man" in the set of men who are tall(*), it tells us nothing, however, if we have a set of people, with one outstandingly greater in height than others, than "the tall man" does achieve the second purpose once we restrict the domain of discourse (in sense of Boole).

So, my question, is there a name for this phenomena where we implicitly constrict the domain of discourse in usage of definite articles?

Or, is there a totally different conceptual starting point to understand this phenomena from?

*: It doesn't even make grammatic sense since the set of men who are tall is many in number

Answer 1

The purpose of the language is communication, and the communication is carried out by giving some new information about something the listener already knows, that is, about some old information.

In linguistics, topic, or theme, of a sentence is what is being talked about, the old information, and the comment (rheme or focus) is what is being said about the topic, the new information. I prefer calling them theme (“old”) and rheme (“new”).

In fact, the two kinds of the English article, definite and indefinite, correspond to these two parts of the sentence:

• theme — the, definite, “that, the one we know about”
• rheme — a/an, indefinite, “some, one of the many existing ones”

During the discourse, the entities constantly change their roles, since as soon as we learn something new about a thing, this knowledge momentarily becomes old, and more new stuff is told about it, which, in its turn, at once becomes old again. Hence the practical rule that when we mention a thing for the first time, it's used with a/an, but when we mention it again, it should be used with the — a rheme becomes the theme as soon as we go on adding more new information.

Let us consider an example of discourse, I will number the utterances, but they all belong to the same piece of conversation:

1. Last night I had a ... {here's a pause and you're all ears to learn the new info, what exactly I had last night} ... I had a dream. {a dream is the rheme here, the new, so it's with a}
2. The dream was about a ... {you already know about dream, so it's become the theme now, the old, with the, and more new info about it is to follow} ... about a horse.
3. The horse had ... {the above mentioned horse is already known so it's a new theme, with the} ... had wings. {the new rheme is wings and it's with a zero indefinite plural article}
4. The wings sparkled like ... {Now wings are the topic, definite, and what follows is expected to be indefinite again}

That is how articles function in discourse, they are used for marking the theme-rheme chains. My example is pretty simplified, in real life discourse is often much more complicated and lots of tricky situations occur, still this is the essence of it all.