Linguistic modality

In standard formal approaches to modality, an utterance expressing modality can always roughly be paraphrased to fit the following template:

The set of propositions which forms the basis of evaluation is called the modal base. The result of the evaluation is called the modal force. For example the utterance in (2) expresses that, according to what the speaker has observed, it is necessary to conclude that John has a rather high income:

The modal base here is the knowledge of the speaker, the modal force is necessity. By contrast, (3) could be paraphrased as ‘Given his abilities, the strength of his teeth, etc., it is possible for John to open a beer bottle with his teeth’. Here, the modal base is defined by a subset of John's abilities, the modal force is possibility.

A more elaborate account of formal semantic approaches to modality is given in section 1.

Cross-linguistically, modality can be expressed by a variety of means, such as auxiliary verbs as in the examples (2) and (3), verbal morphology (mood) or adverbs. An overview of the various modal expressions across languages is given below in section 2.