The sensor and the sensible do not stand in relation to each other as two mutually external terms, and sensation is not an invasion of the sensor by the sensible. It is my gaze which subtends color, and the movement of my hand which subtends the object’s form, or rather my gaze pairs off with colour, and my hand with with hardness and softness, and in this transaction between the subject of sensation and the sensible it cannot be held that one acts while the other suffers the action, or that one confers significance on the other. Apart from the probing of my eye or my hand , and before my body synchronizes with it, the sensible is nothing but a vague beckoning. ‘If a subject tries to experience a specific colour, blue for example, while trying to take up the bodily attitude appropriate to red, an inner conflict results, a sort of spasm which stops as soon as he adopts the bodily attitude corresponding to blue’. Thus a sensible datum which is on the point of being felt sets a kind of muddled problem for my body to solve. I must find the attitude which will provide it with the means of becoming determinate, of showing up as blue; I must find the reply to a question which is obscurely expressed. And yet I do so only when I am invited by it, my attitude is never sufficient to make me really see blue or really touch a hard surface. The sensible gives back to me what I lent to it, but this is only what I took from it in the first place. As I contemplate the blue of the sky I am not set over against it as an acosmic subject; I do not possess it in thought, or spread out towards it some subject; I do not possess it in thought, or spread out towards it some idea of blue such as might reveal the secret of it, I abandon myself to it and plunge into this mystery, it ‘ thinks itself within me’, I am the sky itself as it is drawn together and unified, and as it begins to exist for itself; my consciousness is saturated with this limitless blue. But, it may be retorted, the sky is not mind and there is surely no sense in saying that it exists for itself. It is indeed true that the geographer’s or the astronomer’s sky does not exist for itself. But of the sky, as it is perceived or sensed, subtended by my gaze which ranges over and resides in it, and providing as it does the theater of a certain living pulsation adopted by my body, it can be said that it exists for itself, in the sense that it is not made up of mutually exclusive parts, that each part of the whole is ‘ sensitive’ to what happens in all the others, and ‘ knows them dynamically’. As for the subject of sensation, he need not be a pure nothingness with no terrestrial weight. That would be necessary only if, like constituting consciousness, he had to be simultaneously omni-present, coextensive with being, and in process of thinking universal truth. But the spectacle perceived does not partake of pure being. Taken exactly as I see it, it is a moment of my individual history, and since sensation is a reconstitution, it pre-supposes in me sediments left behind by some previous constitution, so that I am, as a sentient subject, a repository stocked with natural powers at which I am the first to be filled with wonder. I am not, therefore, in Hegel’s phrase, ‘a hole in being’, but a hollow, a fold, which has been made and which can be unmade.
(…) Between my sensation and myself there stands always the thickness of some primal acquisition which prevents my experience from being clear of itself. I experience the sensatin as a modality of a general existence, one already destined for a physical workd and which runs though me without my being the cause of it.
(…) any sensation belongs to a certain field. To say that I have a visual field is to say that by reason of my position I have access to and and opening upon a system of beings, visible beings, that these are the disposal of my gaze in virtue of a kind of primordial contract and though a gift of nature, with no effort made on my part; from which it follows that vision is prepersonal. And it follows at the same time that it is always limited, that around what I am looking at at a given moment is spread a horizon of things which are not seen, or which are even invisible. Vision is a thought subordinated to a certain field, and this is what is called a sense. When I say that I have senses and that they give me access to the world, I am not the victim of some muddle, I do not confuse causal thinking and reflection, I merely express this truth which forces itself upon reflection taken as a whole: that I am able, being connatural with the world, to discover a sense in certain aspects of being without having myself endowed them with it though any constituting operation.
Merleau-Ponty, Phenomenology of Perception, 248-252)