The following quotation is reproduced verbatim from Michael Gilleland's classics blog, Laudator Temporis Acti:
Augustine, Sermons 241.2 (Patrologia Latina, vol. 38, col. 1134; tr. Edmund Hill):
They could see their bodies, they couldn't see their souls. But they could only see the body from the soul. I mean, they saw with their eyes, but inside there was someone looking out through these windows. Finally, when the occupant departs, the house lies still; when the controller departs, what was being controlled falls down; and because it falls down, it's called a cadaver, a corpse. Aren't the eyes complete in it? Even if they're open, they see nothing. There are ears there, but the hearer has moved on; the instrument of the tongue remains, but the musician who used to play it has withdrawn. (emphasis added by BV)
Videbant corpus, animam non videbant. Sed corpus nisi de anima non videbant. Videbant enim per oculum, sed intus erat qui per fenestras aspiciebat. Denique discedente habitatore, iacet domus: discedente qui regebat, cadit quod regebatur: et quoniam cadit, cadaver vocatur. Nonne ibi oculi integri? Etsi pateant, nihil vident. Aures adsunt; sed migravit auditor: linguae organum manet; sed abscessit musicus qui movebat.
Read uncharitably, Augustine is anthropomorphizing the soul: he is telling us that the soul is a little man in your head. This uncharitable eisegesis is suggested by inside there was someone looking out through these windows. A couple of sentences later the suggestion is that the open eyes of a dead man see nothing because no one is looking through these un-shuttered windows — as if there had to be someone looking through them for anything to be seen.
The uncharitable reading is obviously false. The one who sees when I see something cannot be a little man in my head. There is obviously no little man in my head looking through my eyes or hearing through my ears. Nor is there any little man in my head sitting at the controls, driving my body. Neither the thinker of my thoughts nor the agent of my actions is a little man in my head. And even if there were a little man in my head, what would explain his seeing, hearing, controlling etc.? A second homunculus in his head?
A vicious infinite explanatory regress would then be up and running. Now not every infinite regress is vicious; some are, if not virtuous, benign. The homuncular regress, however, is vicious. It doesn't get the length of a final explanation, which is what we want in philosophy.
Charitably read, however, the Augustinian passage raises legitimate and important questions.
Who are the seers when we see something? Who or what is doing the seeing? Not the eyes, since they are mere instruments of vision. We see with our eyes, says Augustine, likening the eyes to windows through which we peer. There is something right about this inasmuch as it is not my eyes that see the sunset, any more than my glasses see the sunset. Put eyeglasses on a statue and visual experiences will accrue neither to the glasses nor to the statue. Eyeglasses, binoculars, telescopes, etc., are clearly instruments of vision, but they themselves see nothing.
But then the same must also be true of the eyes in my head, their parts, the optic nerve, the neural pathways, the visual cortex, and every other material element in the instrumentality of vision. None of these items, taken individually or taken collectively, taken separately or taken in synergy, is the subject of visual experience. Similarly for ears and tongue. He who has ears to hear, let him hear. But it is not these auditory transducers that hear; you hear and understand — or else you don't. You cannot speak without a tongue, but it is not the tongue that speaks. You speak using your tongue.
Question is: what does 'you' refer to in the immediately preceding sentence? Who are you? Who or what am I? Substituting a third-person designator for the first-person singular pronoun won't get us anywhere. I am BV. No doubt. But 'BV' refers to a publicly accessible animated body who (or rather that) instantiates various social roles. You could of course say that the animal bearing my name is the subject of my experiences. That would involve no violation of ordinary language. And it makes sense from a third-person point of view (POV). It does not, however, make sense from a first-person POV. I see the sunset, not the animal that wears my clothes or bears my name.
And please note that the first-person POV takes precedence over, since it is presupposed by, the third-person POV. For it is I who adopts the third-person POV. The third-person POV without an I, an ego, who adopts it is a view from nowhere by nobody. There is no view of anything without an I whose view it is.
So I ask again: who or what is this I? Who or what is the ultimate subject of my experience? Who or what is the seer of my sights, the thinker of my thoughts, the agent of my actions, the patient of my pleasures and pains? Two things seem clear: the ultimate subject of my experience, the transcendental subject, is not this hairy beast sitting in my chair, and the ultimate subject, the transcendental subject, is not an homunculus.
Should we therefore follow Augustine and postulate an immaterial soul substance as the ultimate subject of visual and other experiences? Should we speak with Descartes of a thinking thing, res cogitans, as the source and seat of our cogitationes? Is the res cogitans literally a res, a thing, or is this an illicit reification ('thingification')? On this third approach, call it Platonic-Augustinian-Cartesian, there is a thing that is conscious when I am conscious of something, but it is not a little man in my head, nor is it my body or my brain or any part of my brain. It cannot be my body or brain or any part thereof because these items one and all are actual or possible objects of experience and therefore cannot be the ultimate subject of experience. And so one is tempted to conclude that, since it cannot be anything physical, the ultimate subject of experience must be something meta-physical.
This third approach, however, has difficulties of its own. The dialectic issues in the thought that the ultimate subject of experience, the transcendental ego, is unobjectifiable. But if so, how could it be a meta-physical thing? Would that not be just another object, an immaterial, purely spiritual, object? Are we not, with the meta-physical move, engaging in an illicit reification just as we would be if we identified the ultimate subject with the brain or with an homunculus? And what would a spiritual thing be if not a subtle body composed of rarefied matter, ghostly matter, geistige Materie. Reification of the ultimate subject appears to terminate in 'spiritual materialism,' which smacks of contradiction.
But maybe there is no contradiction. There may well be ghosts, spooks made of spook stuff. I told you about my eldritch experience in the Charles Doughty Memorial Suite in which, one night, someone switched on my radio and tuned it to the AM band that I never listened to. Maybe it was the ghost of the bitter old man who had recently had a heart attack and who had threatened to kill me. But who was the seer of that ghost's sights and the agent of his actions?
Do you see the problem? The regress to the ultimate subject of experience is a regress to the wholly unobjectifiable, to 'something' utterly un-thing-like composed of no sort of matter gross or subtle.
Should we adopt a fourth approach and say, instead, that the ultimate subject of experience is no thing at all whether physical or meta-physical? If we go down this road, we end up in the company of Jean-Paul Sartre and Panayot Butchvarov.
But there is fifth approach, homuncular functionalism, which cannot be explained here. The idea is that there is a regress of stupider and stupider homunculi until we get to a level of homunculi so stupid that they are indistinguishable from mindless matter. See here and here.