Assume a sentence which is specified for its information structure. Its meaning is represented as a set of propositions. This set breaks down into two subsets:

.The room is no longer warm.

An informal representation of the meaning of in terms of presuppositions and assertion is as follows:

The analysis of the meaning of a sentence in these terms applies a set of criteria which may be subsumed under the notion of ‘constancy under propositional operations’: If a propositional operation like negation or conversion of sentence type is applied to the sentence, it only changes the assertion, while the presuppositions remain constant. Thus, all of the transformations in and applied to share the above set of presuppositions, but lack the above assertion. (In the particular case of persistence of time spans, switch of polarity is a bit irregular in that a is normally said as #b; but this does not affect the argument.)

.a.It is not the case that the room is no longer warm.
b.The room is still warm.
.a.Is the room still warm?
b.Is the room no longer warm?

Establishment of a referent or a proposition in one of the reference spaces is to be understood as follows:

The latter effect of a presupposition may be illustrated by (the celebrated example) :

.Did you stop beating your wife?

A polar interrogative expects one of the answers ‘yes’ or ‘no’. But this denies the hearer a chance to reject its presuppositions. If he wants to do so, he avoids the expected answers and insteads replies something like ‘But I never did beat her!’.


1 Assertion here does not mean ‘contention’ or ‘claim’. Sentences of all sentence types, not only declarative sentences, have an assertion.