Halliday & Matthiessen (1999: 603):
… the concept of ‘mind’ should be brought into close relation with other phenomena — biological, social, or semiotic. … But once this has been done, the mind itself tends to disappear; it is no longer necessary as a construct sui generis. Instead of experience being construed by the mind, in the form of knowledge, we can say that experience is construed by the grammar; to ‘know’ something is to have transformed some portion of experience into meaning. To adopt this perspective is to theorise “cognitive processes” in terms of semiotic, social and biological systems; and thus to see them as a natural concomitant of the processes of evolution.