Whenever we experience an itch, a mild pain or a tightening of the chest, we already have a background sense of being in a world, regardless of whether the foreground feelings are perceptions of the body or of something else. This background also consists of feeling. The body, in so far as it sets up the world in which we find ourselves, is neither a medium or perception within an experienced world nor an object of perception within that world. It constitutes an aspect of experience that is presupposed by both.
The world-constituting role of the body is recognized by Merleau-Ponty, who contrasts the lived body with the body as an object of experience and thought. The lived body is what I have referred to as the “feeling body”. It is never experienced in its entirety as an object of experience, even though it can undergo differing degrees and kinds of objectification. This is because it is the possibility of experiencing anything at all and therefore something that always remains, at least in part, in the background:
In so far as it sees or touches the world, my body can […] be neither seen nor touched. What prevents its ever being an object, ever being ‘completely constituted’ is that it is that by which there are objects. It is neither tangible nor visible in so far as it is that which sees and touches. (Merleau-Ponty, 1962, p. 92)
For Merleau-Ponty, the lived body is not only directed towards things in the world. It also opens up the world as a space of purposive, practical possibilities, and thus shapes all our experiences, activities and thoughts. Hence an aspect of bodily experience and a sense of belonging to the world are one and the same.
~Matthew Ratcliffe, feelings of being: phenomenology, psychiatry, and the sense of reality p. 107