After a clarification of the concept of 'linguistic force', viewed both as the syntactical element of mood and the features defining categories of speech acts, A. expresses the belief that the indicative mood is basic (because only sentences in this mood can be used to express truth conditions for any sentence), the interrogative and imperative being transformations. This view of the role of the indicative mood is used to formulate truth conditions to clarify the semantics of language in poetry.