Discursive functions of evidentials and epistemic modals

The present paper analyzes evidentials and epistemic modals in terms of their contribution to the illocutionary act. In indicating how the speaker acquires knowledge about a thing, event, or situation in the world (by evidentials), or what epistemic attitude s/he has towards a thought (by epistemic modals), the speaker performs a particular expositive illocutionary act: the act of describing the world, showing a view, expressing knowledge or belief, and developing an argument. In performing the act, the speaker invites the hearer to share the knowledge about the thing, event, or situation, or the epistemic attitude toward the thought. Austin’s speech act theory is revisited and developed to put forward the idea that expositives bring about effects on the on-going discourse, and that evidentials and epistemic modals play discursive functions by indicating those acts.