Johnson 2004 - CDLI - UCLA

In both (15a) and (15b), the focused part of the sentence is negated, but the presupposed
part of the sentence is not: thus, even if (15a) and (15b) are true, someone in (15a) still
has a husband, and Mary will still likely go to jail for assault in (15b). But specialists in
semantics have actually expended quite a bit of energy attempting to differentiate focal
presuppositions as in (15) from the logical presupposition involved in some of the
examples at the beginning of the chapter such as (2), repeated below as (16).
(16) a. I don’t regret leaving London.
b. I left London.
The sentence in (16b) would only be a focal presupposition if the focus structure in (16a)
were as in (17a) below.
(17) a. I don’t REGRET leaving London.
b. I don’t regret LEAVING LONDON.
The example in (17a) carries the implication that there is some other emotion that the
speaker feels toward his or her departure from London, which is not the case in (16a),
where the somewhat artificial omission of focal intonation forces the reader to fall back
on other interpretive principles such as the factive character of “regret” (Kiparsky and
Kiparsky 1970). The contrastive focus in (17b) explicitly excludes (16b) as
presupposition. Clearly focus introduces an orthogonal dimension to questions of
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