Fish is arguing that what grants us "protection" against the indeterminacy
of signifiers is that they "emerge only in situations, and within those
situations, the normative meaning of an utterance will always be obvious or at
least accessible".
This means that meaning, although determined, is always relative to the
situation in which the utterance appears. What enables us to rank interpretations
is that norms will almost always favor one over the other. Understanding "is there a text in this
class?" as referring to the syllabus of the course will usually come
before, and be accessible to most people, compared with understanding it as an
inquiry about the theoretical view of the course with a contemporary literary debate
(this will be accessible to fewer people who also understand the more lay
meaning of "is there a text in this class?").
Fish debates with E.D.
Hirsch, holding that words do not have meaning which is independent of context since they always
already embedded in context. Fish thinks that what promises us the ability to
have common meaning is that there is always "a contextual setting and the
sign of its presence is precisely the absence of any reference to it".
Even if we hear a sentence without any context we will fall back to context in
which we are accustomed to hear such utterances. Fish claims that there is no two-stage
succession of understanding since an utterance is already determined by its
context. This does not mean we can't misunderstand language but that
misunderstanding is not of semantics and syntax but of context. In the example
of "is there a text in this class?" the professor, according to Fish,
"mispreread the text" and was therefore forced to make another
(pre)determination of the situation. In
order to understand the student the professor had to alter the meaning of her
intentions in approaching him, not the meaning of her words which are perfectly
clear and intelligible in both cases, just in different ways. People unfamiliar
with the literary debate on the determinacy of meaning will have a hard time
reaching the proper understanding while people familiar with Fish's position in
the debate will immediately recognize the proper meaning, especially when they
hear the story coming from Fish himself. The professor in the "is there a
text in this class?" story managed to adjust his interpretation by noting
to himself "Ah, there's one of Fish's victims!".