How can we understand out of body experiences? There on the divan lies Geoff, mid-psychotic episode, or whacked out on drugs, or just dreamy, or an 'astral projection' pundit, and he's taking himself to be floating on the ceiling looking down at his own body. What's going on? Is this pure hallucination? Is it some kind of projection?
My guess is that it's neither. So, I predict that it can't happen if your eyes are shut, and that you can't 'travel' to parts of the room that you haven't been able to see. If I'm right about that then I think that any simple hallucination theory is already scotched. As for projection: well, that's just a 'made up' explanation, since we don't have any clearer an idea of what is meant by 'projection' here than we do of what is meant by 'OBE'. Three more predictions: that what is seen in OBEs are static scenes (even as the 'perceiver' moves about them), and that who has OBEs are people (who are actually) lying still, and that the 'hovering perceiver' of the OBE is experienced not as static but as, even if but a little, moving ('flying') around the room as he 'looks down' on his own body and its environs.
Why is it hard to grasp this? I think it is because we are, even today, relentlessly attracted to representationalism in our theories of vision. So we think of perception as reception of information from the environment; we take for granted the constitution of the subject; we imagine that in perception visibilia are simply presented, re-presented even, to a pre-constituted body subject. Or we imagine that the fact that the constitution of the body subject is transcendental somehow makes it not a part of the world, not a co-constituted, constantly re-enacted, empirically ascertainable fact. We relentlessly take the constitution of the subject for granted. (This explains, too, why we are constantly drawn to misunderstand psychosis in merely epistemic terms - as if it were simply a matter of a self-same subject making mistakes in his perception and in his belief.)