While the study of language has been approached from a wide range of perspectives and theoretical assumptions, it is widely assumed that language structure can be reduced essentially to a fairly monolithic system of mental and linguistic activity. Some recent lines of psychological, linguistic, and neurolinguistic research suggest, however, that human cognitive behavior in general and linguistic discourse in particular exhibit a dualistic organization. In accordance with this research tradition, the present paper argues that there is a basic distinction between two domains of linguistic discourse and that this distinction shows a number of correlations with neural processing, more specifically with hemispheric lateralization of the human brain. Keywords: Discourse grammar , lesion studies , priming , right hemisphere , human brain , situation of discourse , social context , speaker context , speaker-hearer interaction , text organization , thetical. Some lines of recent research suggest that human cognitive behavior in general and linguistic discourse in particular cannot reasonably be reduced to one monolithic system of mental processing.