This article begins by asking whether boundaries can be assigned to discourse analysis. It suggests making a distinction between 'discourse linguistics' and 'discourse analysis', which has a specific viewpoint on discourse. It propounds next to open to research the field of 'self-constituting discourses', thus bringing together those discourses that legitimate the whole discursive production, such as philosophical, scientific or religious discourses. Lastly the article emphasizes some characteristics of such discourses and presents concepts that are useful in analysing them - particularly 'scenography', 'linguistic code', and 'ethos', and offers illustrative examples.