Keelefilosoofia raamat
But when
S1 presupposes S2 and S2 is false, then S1 does not go false, but lacks truth-
value, and so does S1's negation.5 Notice that presupposition in this sense
(called semantic presupposition) is like entailment and unlike conversational
implicature in being noncancelable. Both S1 and S1's negation necessitate S2 in
the absolute way characteristic of entailment.
There are actually no uncontroversial examples of semantic presupposi-
tion. But here are a few candidate sentence pairs.
(7a) It was Grannie who robbed the diaper service.
(7b) Someone robbed the diaper service.
(8a) Have you stopped beating your spouse?
(8b) You have beaten your spouse.
(9a) Rocky realized that his fly was open.
(9b) Rocky's fly was open.
(10a) Fred, who was fat, could not run.
(10b) Fred was fat.
(11a) She was poor but she was honest.
annaabi.ee 
