David Lobina in Inference Review:
Consider these three lines:
—Is it your view, then, that she was not faithful to the poet?
Alarmed face asks me. Why did he come? Courtesy or an inward light?
—Where there is a reconciliation, Stephen said, there must have been first a sundering.1
The text is Ulysses, and the author, of course, is James Joyce. The first line records direct speech. Someone is saying something. So, too, the third line. In interpreting the first and third line as readers, we accept the convention that what a character says expresses what he means. The second line is different. It represents, or depicts, an interior monologue. It is easy enough to paraphrase the monologue from the outside. Stephen thought or observed that the face was alarmed; he thought that it expressed a question; he wondered; he asked. The second line itself represents, depicts, or expresses Stephen’s point of view. That is why it is an interior monologue. Does the interior monologue express Stephen’s thoughts? If so, was he using these very words, and if these very words, are they his thoughts? Or is he, in fact, still another reader describing his thoughts by these particular words when, in fact, very many other words would do as well? These are not easy questions to address.
Opinions have been endlessly divided. In the Theaetetus, Plato described thinking as “a talk which the soul has with itself.”2 If the soul is talking to itself, in what is it talking? Attic Greek? Do those interior voices admit of a still further interior monologue?
More here.