Illocutionary Negations
Another notion Searle and Vanderveken use is that of an 'illocutionary negation'. The difference of such an 'illocutionary negation' to a 'propositional negation' can be explained by reference to the difference between "I do not promise to come" and "I promise not to come". The first is an illocutionary negation - the 'not' negates the promise. The second is a propositional negation. In the view of Searle and Vanderveken, illocutionary negations change the type of illocutionary act.
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