I suppose most people have had the experience of a word losing meaning after incessant repetition. Sometimes philosophy feels like deliberately inducing this experience.
One concept I struggle to understand is ownership, especially in relation to two related philosophical discussions: ownership of our bodies, and ownership of consciousness. (This has come up because I've just read an article with my Bioethics class about end-of-life decision making that raises the question whether we own our bodies.)
In everyday life, things do appear to me as mine. What I experience as most mine is what I pick up most often, what I touch, and what figures into my doing and dealing with the world. The nearer and more constant this touch, the more my own these things seem. Things are more or less mine. Almost nothing is more mine than the computers and keyboards I touch daily. Oddly, the guitar I touch daily is less mine. This is because it resists in ways the computers don't. The more mine something is, the more accessible it is to my touch, and the more I take it up into an overall movement, without resistance. The same thing can be more or less mine over a brief time span. My bicycle, most mine as I crank at high speed and blow through stop signs, can instantly be less mine when the brakes fail to respond or the gear slips.
I experience ownership of these things, through their intimacy, but also through their difference from me. As familiar as it is, the keyboard still is not my fingertips, but belongs to my fingertips. As fluidly as playing the guitar sometimes is, the guitar is always present in relation to my fingers and ears and eyes, etc. (Unlike Merleau-Ponty's famous blind-man's stick, these things I own are not extensions of my body, not appropriated into embodiment.)
So, owning my body strikes me as strangely distancing. Even when I touch my body, I don't touch my body the same way I touch things, and it is not, for me, accessible, near, nor even intimate. There is a divisibility of time and space in the relation of ownership that is not present in my embodiment. This may be a badly strained analogy, but I'll go with it anyway: if ownership is like time, embodiment is like eternality. (And for now I'll sidestep the question of embodiment sub specie aeternitatis.)
Even when my body is objectified and obtrusive, in pain or disability, I say "mine" about my body metaphorically or by extension from the way I say the guitar is mine. I say "my feet hurt," but my feet are not in relation to me the way my bicycle is. I don't feel that I approach the world through my feet or my hands, or walk or touch with them. They are my walking or touching, and in condition of pain or disability, they are the pain-and-walking or the unable-and-touching.
Still stranger to me is the notion of consciousness as ownership. In Husserl's account of the phenomenological reduction, the Ego appears, and with it, the Ego's "own" experience. When I first read this, I was stumped by it, and I still am. Husserl seems to need the Ego and its experience to coexist in this little copula, "own," in order to find a way toward a transcendental ego. Many phenomenological philosophers would be gravely concerned by the notion that the transcendental ego just is experience, and I'm not sure I would advance that proposition (at least, in public), but that would be the parallel construction to the above notion of being the body.