Maurice Merleau-Ponty on the Phenomenology of Perception:

Merleau-Ponty, Maurice [Internet Encyclopedia of Philosophy] - The Critique of the Phenomenology of Perception

 The Visible and the Invisible does attempt to effect a transition from something like a phenomenology of consciousness (which is basically just an analysis of how the objects we perceive present themselves to us), to a philosophy of Being. Being is another of those words in philosophy that is frequently thrown around, but perhaps relatively rarely understood. This is partly because it is not something that we can pin down or define, because it exceeds all of our resources for attempting to describe it. Let us suggest, hesitatingly, that Being is that which allows existence to be possible at all, and Merleau-Ponty becomes increasingly concerned with such matters. 

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Merleau-Ponty also makes one other important comment about the Phenomenology of Perception, and his reasons for writing a new ontology, which is worth exploring. According to him, a major factor behind him setting out upon this different path, was the conviction that the tacit or pre-reflective cogito of his earlier philosophy is problematic (VI 179). The pre-reflective cogito is basically just the idea that there is a cogito before language, or to put it crudely, that there is a self anterior to both language and thought that we can aim to get in closer contact with. The notion of a pre-reflective cogito hence presumes the possibility of a consciousness without language, and it exhibits something of a nostalgic desire to return to some brute, primordial experience. This is something that thinkers like Irigiray have criticized Merleau-Ponty for, and in The Visible and the Invisible he has come to share these type of concerns.  

In his own words, he suggests that while this concept of the pre-reflective, or tacit cogito, can make understood how language is not impossible, it nevertheless cannot make understood how it is possible (VI 179). While a logician might grimace at such a suggestion, Merleau-Ponty is certainly aware of this paradox, and seeks to explicate the problems that he associates with this concept of the tacit cogito. He suggests that like all other philosophies of consciousness, his notion of the pre-reflective cogito depends upon the illusion of non-linguistic signification and The Visible and The Invisible attempts to call into question the very coherence of such a concept. As he states in one of his “Working Notes”:

•  “What I call the tacit cogito is impossible. To have the idea of thinking (in the sense of thought of seeing and thought of feeling), to make the phenomenological reduction to the things themselves, to return to immanence and to consciousness, it is necessary to have words. It is by the combination of words that I form the transcendental attitude” (VI 171).

He later goes on to speak of the “mythology of self-consciousness to which the word consciousness refers”, and contends that “there are only differences between significations” and language (VI 171).

According to Merleau-Ponty, the tacit cogito is therefore a product of language, and the language of the philosopher, in particular. He continues to speak of a world of silence, but the concept of the pre-reflective cogito imports the language of the philosophy of consciousness into the equation, and hence misrepresents the relationship between vision and speech. The famous phenomenological reduction to the things themselves, which tries to bracket out the outside world, is hence envisaged as a misplaced nostalgia rather than as a real possibility.