Halliday & Matthiessen (1999: 137-8):
Here projection turns out to be a major characteristic distinguishing between different types. Sensing projects ideas into existence; the projection may take place either through cognition or through desideration, for example (from Pinter, The Birthday Party):
I just thought —> I'd tell you that I appreciate it.I think —> I'll give it up.They want —> me to crawl down on my bended knees.
Thus the idea 'I'll give it up' is created by the process of thinking; it does not exist prior to the beginning of that process. Similarly, the idea 'me to crawl on my bended knees' is brought into hypothetical existence by the process of wanting.
In contrast, perceptive and emotive types of sensing cannot project ideas into existence. That is, ideas do not arise as a result of somebody seeing, hearing, rejoicing, worrying, grieving or the like. However, these two types of sensing may accommodate pre-existing projections, i.e. facts; for instance:
It assures me [[that I am as I think myself to be, that I am fixed, concrete]].I was impressed, more or less at that point, by an intuition [[that he possessed a measure of sincerity the like of which I had never encountered]].We heard [[that you kindly let rooms for gentlemen]].
Thus 'that I am fixed, concrete' is construed as something already projected (hence we could add assures me of the fact that) and this fact brings about the emotion of assurance.
These features are summarised in Table 4(2).
