Prosthesis is a boundary marker between that which is human and that which is cultural. It points to the incompatibilities of nature/culture, body/machine, normal/abnormal, and other delimiting dualisms.
Prosthesis is an extension of ourselves. The wheel as an extension of the foot, clothing as an extension of the skin, and electric technology as an extension of the central nervous system.
Prosthesis is the essence of technology. With all his tools, man improves his own organs. Ships, aeroplanes, telescopes and cameras, gramophones and telephones all these afford man the omnipotence and omniscience he attributes to his Gods.
A Prosthesis is contra to merleau-ponty who argues that is an extension of our body, instead a full-on replacement for our capacity to see, stripping the experience from the body.
Prosthesis is an extension of the body (via media such as a t.V. Or a set of bike wheels) which, though extending our perception, also amputates it by numbing it or blocking the ability to feel intensely with the body.