Sentences that differ in arrangement and sentence accent also differ in meaning, although their propositional content may be the same. As Bolinger puts it, discussing the difference between active and passive (1977:9):
The classical case is the passive voice. If truth value were the only criterion,
we would have to say that John ate the spinach and The spinach was eaten
by John are the same. They report the same event in the real world. The same
entities are present, in the same relationship… Linguistic meaning covers a
great deal more… "it" expresses, sometimes in ways that are hard to ferret
out, such things as what is the central part of the message, what our attitudes
are toward the person we are speaking to, how we feel about the reliability of
our message, how we situation ourselves in the Events we report, and many
The meanings that Bolinger talks about involve the way a text presents information, its presentational structure.
Surface structure presentation instructs the receiver about how to organize the information in a sentence. The sentences of a text are not undifferentiated wholes, nor simple linear arrangements of words. I adopt the approach to presentation originally put forth by Prague School linguists and further developed in recent years. This approach uses the notions of communicative dynamism, topic–comment, and focus–background, to understand the internal organization of sentences and how they are deployed in texts. Although "topic" is notoriously difficult, I hope to show that it contributes an important dimension to the analysis of sentences and texts.
The writer's choices of how to present material are influenced by assessment of what is accessible to the receiver. The familiarity status of information is a key factor. This notion was introduced in Chapter 6, where it was shown that the forms of referring expressions used in a text tend to correlate with familiarity of the referent. Familiarity status concerns whether information is discourse-old or discourse-new, hearer-old or hearer-new. What is new to the discourse needn't be new to the hearer; but discourse-old is also hearer-old.