Maurice Merleau-Ponty's phenomenological philosophy suggests the search for the self and consciousness need not be focused on the space within our skulls. Instead, we should turn our attention to the lived body.
Our scientific and philosophical search for the self and the place of consciousness in the world has tended to focus between our ears -- although Descartes, as the originator of the modern mind-body problem, held the conscious mind had (as non-material) no location. In the last hundred years or so, materialist-leaning theories have been especially inclined to locate mind and self in the head. In both computational/information-processing and biological theorizing about consciousness and the self, the question to be answered is often seen as one about where to localize this mind/self -- whether those critical properties were best modeled as information processing or as more fundamentally biological.
This is sometimes such a fundamental background assumption that it's even taken by some as fueling a kind of reductio ad absurdum argument against understanding consciousness or the self within a scientific perspective: Reasons for skepticism about reduction or localization of consciousness and self are commonly taken as reasons to infer that we should either (a) prejudge eventual failure for any attempt to scientifically explicate consciousness and self (as advocates of the "unbridgable explanatory gap" like David Chalmers do), or (b) get rid of the notions entirely, as (as anti-self “illusionists” like Thomas Metzinger suggest).
Merleau-Ponty focused on the ways in which our embodiment is central to our consciousness and self.
But in the second part of the twentieth century and continuing into the twenty-first, we've seen movement toward a broader conception of consciousness and self, and no philosopher has been more central in instigating and supporting this idea then Maurice Merleau-Ponty. In particular, Merleau-Ponty focused on the ways in which our embodiment is central to our consciousness and self, pushing away from seeing these as isolatable and reducible phenomena inside the brain and toward seeing them as more distributed and relational features of our lives in the world.
To see the nature of this turn, we need to clarify what the body is taken to be in Merleau-Ponty's outlook. The central role of the body for him is not what we (following him) might call the fleshy body. It is not the body that I see in the mirror, weigh on the scale, treat with medicine; it is not my body taken as an object among other objects in the world. Rather, he has in mind what he calls the lived body, which differs from the fleshy body most centrally in two ways. One, it encompasses aspects of the brain, the sensory organs, and the extension of our biological bodies into the world by means of tools and other familiar objects (such as the blind person's cane); and two, the lived body is our embodiment not as one more object in the world, but as the implicit conduit and mediator of our consciousness of the world.
The lived body is most centrally what accomplishes perception -- the form of consciousness he takes as most fundamental and primordial. Perception is for him an activity of our body in seamless engagement (or as he says, "communion") with the world. It grasps the world, both literally in actions, but more radically, in perception. The lived body for Merleau-Ponty extends from the edge of consciousness where we are aware of things, to the world in which those things are seen felt and heard.
For Merleau-Ponty, perceptual experience is a distinctive phenomenon that should not be mistaken for raw sensation; unlike sensation, perceptual experience is given to us as structured, a unified whole, and as about things in the world. But neither should it be seen as our judgments about the world; how we see things isn't the same as and how we take them to be. If it were, there'd be no room for understanding the mismatches of perception and judgment that show up in persistent illusions and gestalt shifts.
Bodily perception for Merleau-Ponty is most centrally characterized by three features. First, it is an independent active synthesis in that it follows its own rules and processes, synthesizing the perceptual whole. The presentation of the mug on the table as a mug, or your utterance of "the cat is on the mat" takes lots of clever synthesis of cues, but not by me as conscious act. Perception presents the object as already unified and formed by an automatic and unavoidable activity of my lived body.
Second, it is opaque in that its synthesizing is often invisible to my consciousness as well. So, for example, I have no real access to the rules or processes by which my body synchronizes with the utterances of others to present them to me as words, assertions, and the like; nor to strategies by which it synthesizes shapes and objects from the fluctuations of light. Perception takes for granted these opaque activities without providing me knowledge of their internal nature. So, my visual activity is really good at teasing apart the effects on my retinal image of scene illumination from those caused by different colors of surfaces. By doing so, it provides me with information about constant colors across differences in light and shadow, but how it does all this is hidden from my consciousness.
And third, perception is non-thetic presentation in that it does not present itself as an object for experience, but presents something else -- typically, something like the properties of distal objects. Perceiving red, or squareness, or a chair, is not phenomenologically experiencing the result of the independent opaque synthesis as itself. Rather, it's typically having an experience where that result itself is in a sense "invisible". We don't have consciousness of it, but consciousness via it of the worldly objects and features it presents -- something distal as red, or square, or whatever. Perception phenomenologically places what it gives to experience in the world, not in us. As Merleau-Ponty says, I "abandon myself and plunge into it."
This picture puts the realm of consciousness in stark contrast to a Cartesian-inspired view of a separable realm of indubitably known experiential atoms of sensory experience or qualia.
This view takes our fundamental perceptual experience as having the content of external and distal objects (via its non-thetic nature), and takes the unity of brain, body, and world (accomplished by independent synthesis) as experientially non-decomposable (because opaque). This picture puts the realm of consciousness in stark contrast to a Cartesian-inspired (but often materialist) view of a separable realm of indubitably known experiential atoms of sensory experience or qualia. And perhaps most importantly, this alternative possibility casts a different light on some contemporary worries about consciousness and the self.
Because the most basic contents of consciousness are taken as fundamentally inseparable from the brain/body/world unity, the unity of the self that presents to us is the embodied self; it is given to us as our engagement with the physical (and social) world in perception and action. We should not look for it as localizable neural or computational activity, but as being distributed in activity. And if we do stop assuming that there should be a localized and isolable candidate for reductive identification of self and consciousness, arguments grounded in the assumption that there should be such a thing may dissolve. Objects of "inner" consciousness are deprecated on this view; the idea that consciousness is constituted by some kind of sense-data or qualia becomes an artifact of a view left behind.
The idea that consciousness is constituted by some kind of sense-data or qualia becomes an artifact of a view left behind.
Arguments against the idea of consciousness and self are often fundamentally arguments against the reductive, localized, and inner notion. So, for example: Contemporary "explanatory gap" arguments that claim that conscious experience can never be given any real explanation by neural, cognitive, or other kinds of scientific theories standardly rely on the assumption that the paradigm of conscious experience is something like qualia -- simple, unstructured, non-intentional, primitive, non-decomposable components -- which we can consider in complete isolation from their embodied and functional nature of our real activity and experience. An atomistic view of experience encourages puzzling about why we get one mapping between brain states and consciousness rather than some other (or none at all); but moving away from it to a more distributed and embodied our view of consciousness should discourage thinking of it as only optionally and arbitrarily connected to states of neurocognition. The more we follow Merleau-Ponty’s lead here, the more the intuitions these arguments appeal to may be undermined.
Merleau-Ponty's view of (especially perceptual) consciousness as fundamentally a matter of the lived body in "communion" with the world does not demote or minimize the role of consciousness. But it does share with contemporary "illusionist" views of consciousness the idea that it's time to reject a kind of localized internalism of qualia about consciousness, and to move toward seeing consciousness and self not as things to be found in an inner place, but to see that the only conscious self we do have is the one embodied and immersed in the world.