Halliday & Matthiessen (1999: 584):
The everyday grammar's contribution to the construal of sensing is thus both rich and varied. Some features of it are particularly significant to the uncommonsense model of mainstream cognitive science. The grammar separates out consciousness from the rest of our experience in the form of mental processes, capable of projecting ideas; but in addition, consciousness may also be 'externalised' in the form of verbal processes, capable of projecting locutions.